8051 Microcontroller FAQ

8051 Microcontroller FAQ

 Online Since 1996        This Page Last Revised 17 Aug 2000  

The Official 8051 microcontroller FAQ

Note: this page is outdated and no longer maintained

This article is a collection of information sources on the Intel 8051 family of microcontrollers (and variants).

Author: Bill Giovino/FAQs Manager (see submission comments)
8051 FAQ Home Page: http://Microcontroller.com

Archive-name: microcontroller-faq/8051
Posting-Frequency: monthly
Official home location for this FAQ: http://Microcontroller.com/embedded/references/faqs/8051-microcontroller-faq.htm
Last Revision: 19-July-2000

Notice on January 24, 2000
On September 28, 1999, Russ Hersch passed ownership of the 8051 FAQ to Microcontroller.com. Although somewhat out of date,
we are committed to modernizing this FAQ to make it reflect the current state of the 8051 community. Our gratitude goes to
Russ Hersch for all his diligent work over the years.

No advertising will be accepted on this FAQ page.

The following topics are addressed:

0) Rantings and ravings (to make the FAQ zero-based)

1.1) Who put this FAQ together?
1.2) How can I contribute to this FAQ?
1.3) What newsgroups will this FAQ be posted to?
1.4) May I distribute this FAQ or post it somewhere else?
1.5) How about FAQs on other microcontrollers?

2) ABOUT THE 8051
2.1) The 8051 microcontroller
2.2) 8051 Flavors
2.3) 16-bit 8051 parts
2.4) 8051 representatives and approximate prices
2.5) Common and New 80x51 variants
2.6) Advantages realized in implementing control applications on
this family of microcontrollers
2.7) Getting started
2.8) Technical Questions and Answers

3.1) FTP sites
3.2) Web pages [updated 16-July-2000]
3.3) Mailing lists
3.4) BBSs (removed July 2000)
3.5) Help available!

4) 8051 PRODUCTS
4.1) Free languages and development tools
4.2) Free C compilers [updated 16-July-2000]
4.3) Commercially available products

5.1) Periodicals
5.2) Books
5.3) Miscellaneous documentation

back to top

0) Rantings and ravings by Russ Hersch

Disclaimer: Just so it is understood, the "rantings and ravings" are my rantings and raving. My readers are refined and
sophisticated and would never rant or rave. I, on the other hand, sit in front of the TV in torn underwear and drink beer out
of the bottle.

I would be happy to hear ideas on how this FAQ could be improved for the reader. If it makes MY job easier, then that's
even better.

OK, with that out of the way, let's get on with it...

Students at the Universidade Federal de Santa Catarina, Brazil developed a "Remote Lab for the 8051". You send a machine code
of the 8051 to a remote host (where there is 8051 board plugged in the PC) and receive the values of the registers. Study the 8051
microcontroller, without buying a board. For more information: http://www.inf.ufsc.br/~jbosco/labvir.htm

Take care,

Uncle Russ

back to top


1.1) Who put this FAQ together?

PART 1 - by Uncle Russ
I was prompted to put this FAQ together in response to my own frustration in searching for information, and to the constant
occurrence of requests for information on this subject in various newsgroups. Hopefully others won't need to go through
what I did.

Normally, I spend all day programming in assembler or C on an IBM PC. With my hobbyist hat on I decided to try my
hand at a little microcontroller project design. When it came time to start, I had no idea what to do. I had nothing to
start with - no assembler, no programming language, no simulator. I cobbled together a simulator to help me learn about
the workings of the chip. It's not being made available to the public since I'm afraid the simulator isn't very
good. It was for my own use, so the user interface (there is none) really sucks eggs.

I decided to search the net for information on the 8051. This list was compiled the hard way, logging onto every anonymous
ftp site I could find and looking around. I also used Archie, other FAQs and lists, and every reference to the 8051 that
appeared in the various news groups. It took a long time till stuff finally started popping up. I saved all of my notes and the
result was the first version of this FAQ. Responses have been pouring in, and the result is a much
more complete and thorough FAQ.

PART 2 - by Bill Giovino
This FAQ was posted and transferred to Microcontroller.com on 24-Jan-2000. Russ has done an excellent job of maintaining
this FAQ, but his baby son insists on taking his time away from his "web duties". I gladly took over for Russ and am now
engaged in the painstaking task of updating this work. painstaking because a lot is happening with the 8051 and
embedded systems in general. My first order of work will be to update and correct the material already present
in this FAQ. Second will be to add additional material to this work.

1.2) How can I contribute to this list?

I please ask that if you have any suggestions or additions, or you would like to correct any of the information contained herein, please send me a note.
from people who send me nothing but "add me to this FAQ", without mentioning where their listing should go. It takes
a lot, I mean A LOT of work to manage a FAQ like this and I do it in my spare time, whatever that is. The more difficult
or cryptic your FAQ suggestion, the less likely I will include your suggestion. Now, having gotten that out of the way, the
list of individuals who have made significant contributions and have sent suggestions and encouragement is endless.
I hope it suffices to say "Thank you to all who have contributed to this FAQ - we all appreciate it." Special thanks to 
contributors: Paul Stoffregen of SourceForge and Blue Earth Research. If you are a manufacturer and have a web site that supports the 8051, please let meknow so that I can add it to this FAQ. Also, please feel free to update me on new products. Remember to tell me what section to add the info to.

1.3)  Where will updates to this FAQ be posted to?

    Update announcements on this FAQ will be posted in the "About This site" section on the
    home page of Microcontroller.com.

    Info on this FAQ will be posted to the following newsgroups:
    These newsgroups often contain discussions, announcements, or information on the 8051.
    Check them out from time to time.

    You might also want to check out the following newsgroups, since they quite frequently
    have discussions about the 8051 and other microcontrollers:

    A bit farther afield, but still of possible interest:

1.4)  May I distribute this FAQ or post it somewhere else?

    I am putting no restrictions on the use of this FAQ except:
     1. It must be distributed in its entirety
     2. The copyright notice must remain intact
     3. No financial gain may be realized from it

    For this reason a copyright statement is appended to the end of this FAQ to protect
    ourselves.  The copyright does not limit the use of this list for noncommercial purposes.
    I hereby give my permission to one and all to pass this list around and post it wherever
    you want - as long as the above three conditions are met.

        Thank you.

1.5)  How about FAQs on other microcontrollers?

    If anyone wishes to start a FAQ on another microcontroller, please feel free to copy the format of this FAQ - I don't intend on
    copyrighting the look and feel ;-).  With a common format, we will all benefit when trying to find information on a particular

    Other Microcontroller FAQs

      Subject:  68hc11 microcontrollers
      Newsgroups:  comp.realtime
      Archive:  rtfm.mit.edu :  <plus all mirror sites>
      Maintainer:  Robert Boys - Ontario, Canada
                   Email: rboys@best.com
                   Russ Hersch (maintainer emeritus :-)

      Subject:  Microcontroller primer and FAQ
      Newsgroups:  comp.sys.intel
      Archive:  rtfm.mit.edu :  <plus all mirror sites>
      Maintainer:  Russ Hersch
                   Email: russ@shani.net

    Additional FAQs of interest

      Subject:  I2C protocol
      Newsgroups:  sci.electronics
      Comments:    The I2C bus is a simple 2 wire serial interface
                   developed by Philips.  A number of 8051 variants as
                   well as several peripherals include I2C support.
      Maintainer:  Vincent Himpe
                   Email: Vincent.Himpe@ping.be

      Subject:  Robotics
      Newsgroups:  comp.robotics
      Maintainer:  Kevin Dowling
                   Email: nivek@ri.cmu.edu
                   Smail: Carnegie Mellon University
                          The Robotics Institute
                          Pittsburgh, PA 15213

      Subject:  Electronics
      Newsgroups:  sci.electronics
      Comments:  There are a number of FAQs available in this newsgroup
                 on various subjects.  Among some of the subjects covered
                 are:  LCDs, stepper motors, etc.

      FAQ subject:  Real-time
      Newsgroups:  comp.realtime, comp.answers, news.answers
      Archive:  rtfm.mit.edu : pub/usenet/comp.realtime
      Maintainer:  Mark Linimon
                       Lonesome Dove Computing Services
                       Roanoke, Virginia
                   Email: linimon@nominil.lonesome.com.

      Subject:  Motorola 68K microprocessor line
      Newsgroups:  comp.sys.m68k
      Comments:  without a doubt, one of the finest FAQs ever written
                 (well, of course Bob paid me to say this ;-)
      Archive:  bode.ee.ualberta.ca : pub/motorola/general
                ftp.luth.se : /pub/misc/motorola/faq
                file name of archive is m68kfaq?.zip (? is version)
      Maintainer:  Robert Boys - Ontario, Canada
                   Email: rboys@best.com

    For more detailed information on various 8051 microcontroller parts,
    see the article posted to comp.robotics and sci.electronics which
    provides a tabular cross reference of features and pin counts on a
    wide range of microcontrollers (including the 8051 family).  This
    list was compiled and is being maintained by Roger Nelson

    For more information on various microcontrollers and their features,
    refer to the Microcontroller primer and FAQ listed above.

back to top
2)  ABOUT THE 8051

2.1)  The 8051 microcontroller

    The 8051 is an 8 bit microcontroller originally developed by Intel in
    1980.  It is the world's most popular microcontroller core, made by
    many independent manufacturers (truly multi-sourced).  There were 126
    million 8051s (and variants) shipped in 1993!!

    A typical 8051 contains:
       - CPU with boolean processor
       - 5 or 6 interrupts: 2 are external
                            2 priority levels
       - 2 or 3 16-bit timer/counters
       - programmable full-duplex serial port
         (baud rate provided by one of the timers)
       - 32 I/O lines (four 8-bit ports)
       - RAM
       - ROM/EPROM in some models

    The 8051 architecture is a tad bizarre, but then so are the
    architectures of most microcontrollers due to their specialization
    (check out the PIC for creativity - for that matter, take a look at
    any RISC chip).  One vexing problem with the 8051 is its very
    non-orthogonal instruction set - especially the restrictions on
    accessing the different address spaces.  However, after some time
    programming the chip, you can get used to it - maybe even appreciate

    One strong point of the 8051 is the way it handles interrupts.
    Vectoring to fixed 8-byte areas is convenient and efficient.  Most
    interrupt routines are very short (or at least they should be), and
    generally can fit into the 8-byte area.  Of course if your interrupt
    routine is longer, you can still jump to the appropriate routine from
    within the 8 byte interrupt region.

    The 8051 instruction set is optimized for the one-bit operations so
    often desired in real-world, real-time control applications.  The
    boolean processor provides direct support for bit manipulation.  This
    leads to more efficient programs that need to deal with binary input
    and output conditions inherent in digital-control problems.  Bit
    addressing can be used for test pin monitoring or program control

2.2)  8051 Flavors

    The 8051 has the widest range of variants of any embedded controller
    on the market.  The smallest device is the Atmel 89c1051, a 20 Pin
    FLASH variant with 2 timers, UART, 20mA.  The fastest parts are from
    Dallas, with performance close to 10 MIPS!  The most powerful chip is
    the Infineon Technologies 80C517A, with 32 Bit ALU, 2 UARTS, 2K RAM, PLCC84
    package, 8 x 16 Bit PWMs, and other features.

    Among the MAJOR manufacturers are:
        AMD      Enhanced 8051 parts (no longer producing 80x51 parts)
        Atmel    FLASH and semi-custom parts
        Dallas   Fastest variants. Also battery backed
        Intel    8051 through 80C51GB / 80C51Sl. They invented the 8051
        ISSI     IS80C51/31 runs up to 40MHz
        Matra    80C154, low voltage static variants
        OKI      80C154, mask parts
        Philips  87C748 thru 89c588
        Infineon 80C501 through 80C517A, and a wide variety of CAN devices.
        SMC      COM20051 with ARCNET token bus network engine
        SSI      80x52, 2 x HDLC variant for MODEM use

    Advanced Micro Devices (AMD)

       AMD was one of the first manufacturers of enhanced variants including such features as:
       dual data pointers, slave interface with arbitration unit, dual port RAM, FIFO buffers,
       and others. They are now out of the 8051 business.

       The smallest current device is the ATMEL 89c1051, a 20 Pin FLASH
       variant with 2 timers, UART, 20mA.  ATMEL was the first with
       standard pinout FLASH, and with more program cycles than other
       custom pinout FLASH.  These parts compete with OTP and MASK
       product on price, but eliminate inventory problems and the hidden
       costs of OTP development.  This will put real pressure on
       "vanilla" micros like PIC and ST6.

    Dallas Microcontrollers - DS5000(T), DS5001(T), DS2250(T)
       The Dallas Soft Microcontrollers have standard 8051 cores with
       on-chip non-volatile RAM instead of ROM.  This gives the user the
       ability to easily alter the system and is perfect for data
       logging.  These processors are available in both chip and module
       solutions.  Among the features included in this family of
          - on-chip non-volatile RAM
          - loader in ROM for downloading programs (eliminates the hassle
            of EPROM erase/program/install cycle)
          - built in real time clock option
          - watchdog timer
          - software security (program and data encryption)

       The DS500x is a standard 40 pin DIP package (well, mostly
       standard, it is really a BOX which is about double the height of a
       normal chip).  The DS225x is a SIP version which is functionally
       identical to the DS5000 but usually a bit less expensive.

       The nice thing about having the RAM on-chip, is that the I/O ports
       are unaffected.  When the RAM is configured as CODE memory, the
       DS5000 behaves exactly as a single-chip 8051.  The NV-RAM is
       static with a built-in lithium battery, and has no limitations on
       the number of writes.  You can download your code as many times as
       you like without damaging the device.  The DS5000 also includes a
       loader in ROM, which permits you to bootstrap code into the RAM to
       get underway.  The loader and on-chip RAM have an encryption
       feature with which you can protect your code from being read back
       from the device if you wish.

    Dallas High-Speed Micros - DS80c320, DS87c520, DS87c530
       Real barn-burners - performance up to 8.25 MIPS!  Dallas was the first to speed up the core.
       Wasted clock and memory cycles have been removed using a redesigned processor core.  As a
       result, every 8051 instruction is executed up to 3 times faster than the original for the same
       crystal speed.  External clock speeds from DC to 33MHz!

       High performance doesn't just mean speed.  High integration gives the user 2 full-duplex
       hardware serial ports, 13 total interrupt sources (6 external), watchdog timer, power
       management, power-fail reset, and other features.

       Dallas also has the 80C390, with two CAN 2.0B channels and a math coprocessor.

    Intel MCS-51
       Introduced in 1980, it has become the industry standard for embedded control.  Intel offers
       a wide variety of 8051 versions with different configurations of on-board EPROM/ROM.  Also
       low power, high integration, and specialized parts are also offered.

       Among the Philips derivatives:  40MHz, 24 pin skinny DIP, low voltage, quad flat pack (QFP)
       versions for saving board space, OTP, I2C bus, and so on.

       The c7xx series are very low-end, inexpensive micros.  They are offered with less memory
       (1k, 2k, etc.) and fewer features.

    Infineon C500 Family
       The C500 is one of the most feature rich 8051 families available. The C517A has a high clock speed
       (40 MHz!), and high integration with 32 Bit ALU, 2 UARTS, 2K RAM, PLCC84 package, 8x16 bit PWMs,
       and more. The C515A features a 10-bit A/D, 4 capture/compare units, and a host of other features.

       The C505C, C505CA & the C515C also have CAN 2.0B interfaces. There is also the C541U,
       an 8051 core with an integrated USB interface as well as an MMU.

    Standard Microsystems Corporation SMC COM20051
       The COM20051 is an integrated microcontroller and network
       interface which features:
         -  high performance and low cost
         -  based on popular 8051 architecture
         -  drop-in replacement for 80C32 PLCC
         -  network supports up to 255 nodes
         -  powerful network diagnostics
         -  maximum 512 byte packets
         -  duplicate node ID detection
         -  self-configuring network protocol
         -  retains all 8051 peripherals including Serial I/O and
            2 Timers
         -  utilizes ARCNET(R) Token Bus Network Engine
         -  requires no special emulators
         -  5 Mbps to 156 Kbps data rate
         -  network interface supports RS-485, twisted pair,
            coaxial, and fiber optic interfaces
         -  "receive all" mode allows any packet to be received

    Silicon Storage Technologies
    SST makes the FlashFlex51, an 8051 with very robust Flash memory.
        - Up to 64Kbytes of Flash EEPROM

    Silicon Systems Inc. SSI73M2910/2910A
       The SSI73M2910 is a high performance microcontroller designed for
       modem and communications applications.
         - 8052 Compatible Instruction set.
         - 34 MHz Operation @ 4.5 - 5.5V
         - 44 MHz Operation @ 4.75 - 5.5.V (2910A)
         - 22 MHz Operation @ 3.3 - 5.5.V
         - HDLC Support Logic (Packetizer, 16 and 32 CRC, zero ID)
         - 24 pins for user programmable I/O ports
         - 8 pins programmable chip select logic or I/O for memory mapped
           peripherals eliminating glue logic
         - 3 external interrupt sources (programmable polarity)
         - 16 dedicated latched address pins
         - Multiplexed latched/address bus
         - Instruction cycle time identical to 8052
         - Buffered oscillator (or OSC/2) output pin
         - 1.8432 MHz UART clock available
         - Bank select circuitry to support up to 128K of external
           program memory
         - 100-Lead TQFP package available for PCMCIA applications
         - Also available in 100-Lead QFP package

2.3)  16-bit 8051 parts

    A joint project between Intel and Philips Semiconductors resulted in two new excting
    products - 16 bit 8051s!  Due to a disagreement between the parties, they each went their
    separate ways.  Intel developed the 80251, also called the MCS-251, which was originally called
    the ZX (this name can still be found on one of the Intel slide shows).  Philips came out with
    the eXtended Architecture (XA) line.

    The Intel 80251 is a drop-in replacement for the 8051 (at least, after programming the mode
    control bits first), and is also binary compatible.  The XA is more of a 16 bit micro which
    also happens to be source code compatible.  One can argue the merits of which approach is better.

    Pin compatible parts allow instant performance upgrades for existing designs, and the binary
    compatibility truly preserves a user's investment in code and tools.  By staying firmly in the
    80x51 camp, Intel allows users transparent access to an enormous horsepower range.  To further
    improve throughput in numerically intensive areas, users can use INTEGER, LONGINT, and FLOAT
    libraries written for the 80251.

    The Philips XA is NOT a drop-in replacement for the 8051.

    Binary code compatibility is nice, you can move right up to a more powerful engine without
    having to bust a gut (We all know the Intel binary compatible success story with their
    x86 microprocessors). But if you're working on a new design, how necessary is binary
    compatibility?  If you're just looking for a souped up '51, Dallas already has the 320.  If you
    need the advanced features, or if you need to perform 16-bit math, you'll need to recompile or
    rewrite your software anyhow.  You'll also have to drag along some compatibility baggage with
    you in order to use the 16 bit operations - these are preceded by an escape code (A5H), the
    only instruction not used in the 8051 instruction set.

    With source code compatibility, you have to recompile your code (with a new set of development
    tools), since the instruction set has been recrafted to allow the biggest bang for the buck.

    If you're upgrading an existing design, the 251 is probably your only reasonable and best choice,
    as it has much better development tools than the XA (although you might also want to consider
    the Dallas 320 if you just need to run the same code faster).  On new designs, you'll have a
    tough decision to make. Whichever path you choose to take, the 8051 will never be the same

    Intel 80251 (MCS-251)
       The Intel MCS-251 is 100% binary and pin compatible with the 8051, but with a 5-15 times
       boost in horsepower.  This is achieved by a six fold gain in bus cycles, and further
       hardware improvements to avoid wasted bus cycles.

       Further performance gains are possible by recoding critical sections to take advantage of
       the new features:
       - powerful 8/16/32 bit instructions,
       - flexible 8/16/32 registers,
       - 16MB linear address space,
       - 16-bit stack pointer,
       - enhanced BIT manipulations, and
       - improved control instructions.
       In addition to extra 16/32 bit instructions, the 251 includes 40 registers with Accumulator
       and Index functions overlayed as 16x8, 16x16, 10x32.

    Philips 8051XA
       By tossing compatibility out the window, Philips was able to develop a 16 microcontroller
       while at the same time preserving the basic 8051 instruction set (source).  The benefits
       of this break with tradition result in a chip that has:
       - dual 16MB address spaces (data and code),
       - multitasking support with task protected memory segments,
       - a separate SFR bus,
       - fast context switching,
       - hardware divide and multiply,
       - 32 vectored interrupts, and
       - 16 hardware exceptions
       The disadvantage is that if you have some legacy object code with no source, you have to
       rewrite all the code because you have no binary compatibility. Also, you have to rewrite
       all your code libraries.

2.4)  8051 representatives and approximate prices (in USD $ 1997)
    There are many, many varieties of 8051 out there.  This is only a
    small sampling of typical prices on Intel chips.

        8031 (128 bytes RAM)...................................3.59
        80C31 (CMOS version of previous).......................6.95
        8051AH (256 bytes RAM).................................6.95
        8051AHBASIC (w/Basic interpreter built in)............29.95
        8751 (4K EPROM, 128 bytes RAM)........................26.95
        87C51 (CMOS version of previous)......................39.95

2.5)  Common and New 80x51 variants

    Triscend maes an interesting product - an 8051

    Thanks to Jim Granville of Mandeno Granville Electronics, Ltd. for
    the following nice summary.

        PCA programmable counter array
        LV  low voltage
        PWM pulse width modulation
        CC  capture/compare
        UPI Universal Peripheral Interface (Philips)

    Variant  Pins  Mfg     RAM  CODE XRAM  Notes (LV - low voltage)
    MCS251    40   Intel    1K   16K    0   16 Bit 80X51FX
    80C509L  100QF Infineon 256  64Kx  3K   ALU,PWM,CC,2UART,10bA/D
    80C517A   84   Infineon 256  64Kx  2K   ALU,8PWM,CC,2UART,10bA/D
    80C537A   84   Infineon 256  32K   2K   ALU,8PWM,CC,2UART,10bA/D
    80537     84   Infineon 256  64Kx   0   ALU,8PWM,CC,2UART,8bA/D
    80517     84   Infineon 256   8K    0   ALU,8PWM,CC,2UART,8bA/D
    80C320    40   Dallas  256  64Kx    0   FAST, 2 DPTR 2 UART VRST - fastest 8051
    80C310    40   Dallas  256  64Kx    0   Simpler 80C320 e62.5Mhz - fastest 8051
    87C520    40   Dallas  256  16K    1K   16K OTP enhanced 80C320 - fastest 8051
    DS5000    40   Dallas  128  32KR 32K   80x51 Secure+NVsupport,BootLdr - fastest 8051
    DS2250   40sim Dallas  128  32K  32K   5000, in SIMM package - fastest 8051
    DS5001   80qfp Dallas  128  64Kx 64K   Enhanced DS5000, RPC BatSw
    73D2910 100QFP SSI      256 128Kx   0   80C52+Ports+HDLC
    80C535A   68   Infineon 256  64Kx  1K   515+10bA/D,1K XRAM,BRG,OWD
    80CE558  80QFP Philips  256  64Kx 768   Enhanced 80C552, Sep i2c, RSO
    80C515A   68   Infineon 256  32K   1K   515+10bA/D,1K XRAM,BRG,OWD
    80535     68   Infineon 256  64Kx   0   Timer2CaptComp 6ports 8/10bA/D
    80515     68   Infineon 256   8K    0   Timer2 CaptComp 4 ports 8b A/D
    80C535    68   Infineon 256  64Kx   0   Timer2 CaptComp 5 ports 8b A/D
    80C51GB   68   Intel   256   64Kx   0   8051FA+PCA, 8b A/D, SPI
    87C51GB   68   Intel   256    8K    0   8051FA+PCA, 8b A/D, SPI
    87C598    80   Philips 256   32K  256   552-i2c+CAN+XRAM
    80C552    68   Philips 256   64Kx   0   10b A/D, i2c, CaptComp, PWM
    87C552    68   Philips 256    8K    0   10b A/D, i2c, CaptComp, PWM
    80C562    68   Philips 256   64Kx   0   8b A/D, i2c, CaptComp, PWM
    SABC505C  44   Infineon 256  64Kx 256   8bA/D,XRAM,OWD,CAN V2B, Xt2
    SABC504   44   Infineon 256  64Kx 256   10bA/D,XRAM,OWD,DC Motor PWM
    80C51FX   40   Intel   256  64Kx    0   80C58i+PCA,AsRST
    87C51FA   40   Intel   256   8K     0   8052+PCA,Enh Serial Automotive
    87C51FB   40   Intel   256  16K     0   8052+PCA,Enh Serial Automotive
    87C51FC   40   Intel   256  32K     0   8052+PCA,Enh Serial Automotive
    8XC51FB   40   Philips 256  16K     0   87C51FB with ALE RFI mode
    87C51FXL  40   Intel   256  32K     0   3.3v 80C51FC
    80C152JD  68   Intel   256  64Kx    0   HDLC/SDLC Serial
    80C152    48   Intel   256  64Kx    0   HDLC Serial
    8044      40   Intel   192  64Kx    0   RUPI Serial
    80C575    40   Philips 256  64Kx    0   8052+PCA,AnalogComp,WDOG,RSTLo
    87C575    40   Philips 256   8K     0   8052+PCA,AnalogComp,WDOG,RSTLo
    80C576    40   Philips 256   8K     0 8052+PCA,UPI,A/D,PWM,WDOG,VRSTLo
    87C576    40   Philips 256   8K     0 8052+PCA,UPI,A/D,PWM,WDOG,VRSTLo
    SABC501   40   Infineon 256  64Kx   0   40MHz Enhanced 8052 U/D
    SABC502   40   Infineon 256  64Kx 256   8052+XRAM+8DP+WD+BRG+OWD
    80C528    40   Philips 256  64Kx 256   8052+Wdog, XRAM
    87C528    40   Philips 256  32K  256   8052+Wdog, XRAM
    89CE528   44   Philips 256  32KF 256   Flash 528
    87C524    40   Philips 256  16K  256   16K 87C528
    80C550    40   Philips 128   4K    0   8b A/D WDog
    80CL781   40   Philips 256  64Kx   0   LV 8052, More INTs, WDOG
    83CL781   40   Philips 256  16K    0   LV 8052, More INTs, WDOG
    80CL782   40   Philips 256  64Kx   0   LV, faster 781
    89S8252  40.44 Atmel   256 10KFE   0   FLASH, 8K+2KEE, WDOG, SPI
    89C55    40.44 Atmel   256 20KF    0   FLASH, Fast,LV 87C52+20K
    89C52    40.44 Atmel   256  8KF    0   FLASH, Fast,LV 87C52
    87C54     40   Intel   256  16K    0   16K 87C52i
    87C58     40   Intel   256  32K    0   32K 87C52i
    87C52     40   Intel   256   8K    0   8052+U/D+OscO+4Li
    80C154    40   Matra   256  64Kx   0   Enhanced 8052 (also OKI)
    83C154D   40   Matra   256  32K    0   Enhanced 8052
    83C154    40   OKI     256  16K    0   Enhanced 8052
    80C654    40   Philips 256  64Kx   0   i2c
    87C652    40   Philips 256   8K    0   i2c
    87C654    40   Philips 256  16K    0   i2c
    83CE654  44qfp Philips 256  16K    0   i2c, low RFI 654
    80C851    40   Philips 128  64Kx   0   8051+256B EEPROM
    83C852     6   Philips 256   6K    0   ALU,2K EEPROM SmartCard,Die
    8052      40   All     256  64Kx   0   8051+Timer2
    8752      40   Intel   256   8K    0   8051+Timer2
    80C52     40   Infineon 256  64Kx   0   8051+Timer2,Philips,Oki,Matra
    88SC54C   8    Atmel   256  64Kx 512   8052+PublicKey,prelim
    80CL410   40   Philips 128  64Kx   0   LV, More INTs i2c-UART
    80CL31    40   Philips 128  64Kx   0   LV, More Ints 80x51
    80CL610   40   Philips 256  64Kx   0   LV, More INTs i2c-UART
    83CL411   40   Philips 256  64Kx   0   80CL31 with 256 RAM, No T2
    89C51    40.44 Atmel   128   4KF   0   FLASH,Fast,LV 87C51
    8751      40   All     128   4K    0   Core processor,UART,Tmr0,Tmr1
    87C51     40   All     128   4K    0   Core processor,UART,Tmr0,Tmr1
    8031      40   All     128  64Kx   0   Core processor,UART,Tmr0,Tmr1
    8051      40   All     128   4K    0   Core processor,UART,Tmr0,Tmr1
    80C31L    40   Matra   128  64Kx   0   LV 80x51
    87C752    28   Philips  64   2KE   0   87751+ A/D, PWM
    87C749    28   Philips  64   2KE   0   87C752 - i2c
    87C751    24   Philips  64   2KE   0   Small size, bit i2c
    87C748    24   Philips  64   2KE   0   87C751 - i2c
    87C750    24   Philips  64   1KE   0   Small size
    89C2051   20   Atmel   128   2KF   0   20Pin 89C51,+AnaComp+LED
    89C1051   20   Atmel    64   1KF   0   20Pin 2051 -uart,timer1
    TE502  128/208 Triscend       8K        256 Configurable System Logic (CSL) cells
    TE505  128/208 Triscend      16K        512 CSL cells
    TE512  128/208 Triscend      16K        1152 CSL cells
    TE520  208/436 Triscend      40K        2048 CSL cells

2.6)  Advantages realized in implementing control applications on this family of microcontrollers

    Wildly popular - readily available and widely supported, a full range of free and commercial
    support products is available

    Fast and effective - the architecture correlates closely with the problem being solved
    (control systems), specialized instructions mean that fewer bytes of code need to be fetched
    and fewer conditional jumps are processed

    Low cost - high level of system integration within one component, only a handful of components
    needed to create a working system

    Wide range -  ONE set of tools covers the greatest horsepower range of any microcontroller
    family, other suppliers handle a number of DIFFERENT and INCOMPATIBLE (and often single-sourced)
    cores to cover the same power range as the 80x51, the 8051 provides a real cost savings in tools,
    training, and software support

    Compatibility - opcodes and binaries are the SAME for all 80x51 variants (unlike most other
    microcontroller families)

    Multi-sourced - over 12 manufacturers, hundreds of varieties, something for everyone with the
    security of ready availability

    Constant improvements - improvements in silicon/design increase speed and power annually,
    16 bit models coming from several manufacturers, low cost skinny DIP models and PQFP
    models now available.

2.7)  Getting started
    If you are interested in getting started with the 8051, you will need
    to concern yourself with getting the appropriate hardware and
    software to develop your system.

    A good start would be to pick up a couple of books on the subject.
    Two really great books for beginners are "The Microcontroller Idea
    Book" by Jan Axelson (Lakeview Research) and "Programming and
    Interfacing the 8051 Microcontroller" by Sencer Yeralan and Ashutosh
    Ahluwalia (Addison Wesley).  Both books contain complete plans for
    microcontroller boards/systems if you plan on rolling your own.  The
    Yeralan/Ahluwalia books also contains a diskette with just about all
    of the software that you'll need to get started progamming for the
    8051 (assembler, simulator, etc).  These books also have many circuit
    and code examples and are very useful for the beginner.

    Which software you choose is mostly a matter of personal preference,
    how much time you have to invest, how much money you have to invest,
    and what you want to accomplish.  Serious work can be accomplished
    using much of the free software listed in this FAQ, however in most
    cases technical support is unavailable.  Registering shareware, or
    buying a mainstream commercial package gives you backup and support
    and helps you get going much faster.

    A wide range of development options exists for all budgets and
    purposes.  One convenient way to start is the Ceibo/Philips DS-750
    development system, based on the 80c75x (a scaled down 8051 variant).
    The "emulator" board programs the chips (so you won't need an EPROM
    programmer and the debugger has a user interface much like Borland's
    Turbo Debugger. Phyton also sells a very inexpensive compact emulator that comes
    with a compiler. The emulator itself is very powerful and intuitive to use.

    One other possibility is the 8052AH-BASIC chip.  With a Basic
    interpreter built in, you have an interactive development system when
    attached to your PC.  Jan Axelson's book gives complete coverage on
    this chip, including plans to build your own system, programming in
    Basic, and interfacing to various peripherals and devices.

    What might be the easiest way to get started, is by buying a complete
    development package. The AES-51 from American Educational Systems is
    a good example. This package comes complete with everything you need
    to get started and do real work. The microcontroller board has just
    about every peripheral you'll ever need built right in (LCD, keypad,
    A/D, D/A, I/O, etc) and comes with a built-in monitor and BASIC. Also
    included is a shelf full of tutorial and reference books and a
    diskette with the required support software for your PC. For less
    than $300, you get a complete and professionally designed and
    packaged educational tool. AES also has two other boards (based on
    the 68hc11 and 8088) which have the same basic appearance and

    MDL Labs offers the following BASIC language packages for the 8051:
    1. BASIKIT--Integrated Programming Environment for BASIC-52 & for MDL-BASIC-I, MDL-BASIC-P, and MDL-BASIC-D. BASIKIT
    includes a full-screen editor and permits writing programs with labels rather than line numbers.
    2. MDL-BASIC-I and MDL-BASIC-P are supersets of the original BASIC-52, for the Intel 8052 and the Phillips PCB83C552,
    respectively. All bugs removed.
    3. MDL-BASIC-D is a BASIC for the Dallas 87C530 which accesses all the features of the chip, including both serial ports,
    the Watchdog, and the power-saving features. The BASIC will address up to 512K of memory and will collect data into that
    memory via serial port interrupts. It runs faster at 25 MHz than compiled code on the 8052.
    MDL Labs
    1073 Limberlost Court
    Columbus, OH 43235
    Tel/Fax: 614-431-2675
    Email: arl@infinet.com

2.8)  Technical Questions and Answers

    Q:  Why are ports P0 and P2 unavailable for I/O when using external
    A:  The output drivers of ports 0 and 2, and the input buffers of
        port 0, are used to access external memory.  Port 0 outputs the
        low byte of the external memory address, time-multiplexed with
        the byte being read/written.  Port 2 outputs the high byte of the
        external memory address when the address is 16 bits wide.
        Otherwise, the port 2 pins continue to emit the P2 SFR contents.
        Therefore, when external memory is being used, ports 0 and 2 are
        unavailable for their primary use as general I/O lines.

    Q:  Is there anything I can do to use these ports for I/O when using
        external memory?
    A1: Not really.
    A2: If you really want to make your life miserable, you can try to
        use P2 for output when it isn't being used for memory access.
        The contents of the SFR latch for port 2 are not modified during
        the execution of a Data Memory fetch cycle on the Expanded Bus.
        If an instruction requiring a cycle on the Expanded Bus is not
        followed by another instruction requiring a cycle on the Expanded
        Bus, then the original contents of the port 2 SFR latch will
        appear during the next machine cycle.  That is, when PSEN, RD and
        WR are all inactive, you can use port 2 for output (check the
        timing charts in the data book).  The chip will emit the contents
        of the P2 SFR at that time.  Do you REALLY want to bother with
        this though?
    A3: By including the external RAM "on-chip", the Dallas DS5000 makes
        these ports available for I/O.  The SLIC E2 from Xicor does the
        same thing for other 8051 parts.
    A4: If you really need the extra I/O ports, there are number of 8051
        variants that have additional ports.  Philips and Infineon are two
        such manufacturers that have these parts in their product lines.

    Q:  I'm outputting a 1 to a pin on port 0, but I'm not getting a 1
        out.  If I use a pin on port 1 instead, it works fine.  What am I
        doing wrong?
    A:  Port 0 has open drain outputs.  Ports 1, 2, and 3 have internal
        pullups.  What does this mean?  See the next question and answer.

    Q:  Port 0 has open drain outputs.  Ports 1, 2, and 3 have internal
        pullups. What does this mean, and why should I care?
    A:  When used as outputs, all port pins will drive the state to which
        the associated SFR latch bit has been set.  Except for port 0,
        which will only drive low (not high).  When a 0 is written to a
        bit in port 0, the pin is pulled low (0).  But, when a 1 is
        written to a bit in port 0, the pin goes into a high impedance
        state - or in other words, "disconnected", no value.  To be able
        to get a 1 as output, you need an external pull up resistor to
        pull up the port (to +5V, or 1) when the port is in its high impedence
        state.  Typical values for pullups might be 470 ohm to drive a
        LED, and 4.7K or higher to drive logic circuits.
    C:  Any port pin may be used as a general purpose input simply by
        writing a 1 into the associated SFR latch bit.  Since ports 1, 2,
        and 3 have internal pull-up devices they will pull high and will
        source current when pulled low.  When a port 0 bit is programmed
        for input (set to 1) it will go to a high impedance state.

    Q:  Why is such an oddball crystal frequency of 11.0592 MHz used so
        often for 8051 designs.
    A1: 11.0592 MHz crystals are often used because it can be divided to
        give you exact clock rates for most of the common baud rates for
        the UART, especially for the higher speeds (9600, 19200).
        Despite the "oddball" value, these crystals are readily available
        and commonly used.
    A2: When Timer 1 is used as the baud rate generator, the baud rates
        in Modes 1 and 3 are determined by the Timer 1 overflow rate and
        the value of SMOD (PCON.7 - double speed baud rates) as follows:

           Baud rate =   ------   x (Timer 1 overflow rate)

        Most typically, the timer is configured in the auto-reload mode
        (mode 2, high nibble of TMOD = 0100B).  In this case, the baud
        rate is given as:

                           2        Oscillator frequency
           Baud rate =   -------  x --------------------
                           32         12 x (256 - TH1)

        Some typical baud rates for an 11.0592 crystal:

           Baud rate  SMOD   TH1
             19200      1   0FDH
              9600      0   0FDH
              4800      0   0FAH
              2400      0   0F4H
              1200      0   0E8H
               300      0   0A0H

        Another way to look at it, would be to rework the formula to give
        us the crystal frequency that we need for the desired baud rate:

        Minimum crystal frequency =  Baud rate x 384 / 2

        This gives us the minimum crystal frequency possible for the
        desired baud rate.  The frequency can be evenly multiplied to
        obtain higher clock speeds.

        As an example, the minimum crystal frequency for 19.2K baud is:
              3.6864 = 19200 x 384 / 2 (smod is 1 for 19.2K baud)

              11.0592 = 3.6864 x 3

        To determine the timer reload value needed, the formula can be
        changed to factor in the multiplier:
        Crystal frequency = Baud rate x (256 - TH1) x 384 / 2

        From the example above, the multiplier (3) is used to determine
              TH1 = 256 - 3 = 253 = 0FDH

        The crystal frequency for 19.2K baud is:
              11.0592 = 19200 x (256 - 0FDH) x 384 / 2
                      (smod is 1 for 19.2K baud)

        Other values can also give good results, but 11.0592 is one of
        the higher speed crystals that allows high baud rates.

    A:  Well, you wanta talk about oddball values?  Another good crystal
        value is 7.3728 MHz and its multiples. Using counter1 this gives
        an even 38.4 kbps rate exactly, which is not possible with
        11.0952 MHz Xtal. <Thanks to Eero-Pekka Mand>

    Q:  How do I decrement the data pointer (DPTR)?  Where did the DEC
        DPTR instruction go?
    A1: You can't decrement DPTR.  Although there is an INC DPTR
        instruction, there is no DEC DPTR.  In fact, there is no other
        way to change the contents of DPTR except for MOV and INC.
    A2: You can use the accumulator as an offset if you need to perform
        "calculations" on the DPTR.  As an example:
              MOV   DPTR,#9000         ; load base address into DPTR
              MOV   A,#10              ; load desired offset
              MOVC  A,@A+DPTR          ; retrieve desired data
    A3: Another method would be to use indirect addressing.  Instructions
        such as MOVX A,@Ri can address a 256 byte "page" of external RAM.
        The value represented by @Ri (@R0 or @R1) is emitted to Port 0,
        which is the low byte of the external RAM address bus.  In
        addition, the contents of the P2 register is emitted to Port 2,
        which is the high byte of the external memory address bus.  The
        indirect addressing register together with the P2 register, which
        specifies the "current page number", gives us a 16 bit pointer
        into the external memory address space.

        This technique can make moving data in external memory much
        faster than reloading DPTR every time.  The indirect addressing
        register can be manipulated much easier than DPTR which can only
        be loaded and incremented.  Just remember to make sure that P2
        contains the proper value for the high byte of the address.
    A4: Inside the BASIC interpreter source code, and published in its
        manual, is a short and efficient subroutine to decrement data
        pointer, only 6 statements:
            XCH A,DPL ; JNZ $+4 ; DEC DPH ; DEC A ; XCH A,DPL ; RET
        Only DPTR is affected, not A or any flags!
        <Thanks to Eero-Pekka Mand>

    Q:  I'm trying to PUSH and POP the accumulator, but my assembler
        complains about the instruction  PUSH  A.  What's wrong with
    A:  In instructions that are accumulator specific, A is used to
        represent the accumulator.  However, PUSH and POP have no
        accumulator specific forms, only direct addressing forms.
        Therefore, you need to specify the correct accumulator "address"
        - ACC.  Use the instruction PUSH ACC.

    Q:  The 8052 AH-BASIC interpreter seems to work OK when I perform
        simple interpreted commands.  For example:
             > PRINT "HELLO"
        However, when I try to enter a [numbered] statement, I get an
             > 10 PRINT "HELLO"
             INVALID LINE NUMBER..!!
        I get the same error when I try LIST.  No matter what value I set
        a variable to, it returns a 0.  What's my problem?
    A1: Faulty memory decoding or addressing is the most common cause for
        this error message.  This happens when RD/WR is affecting two (or
        more) active memory chips. So, decode each CS very carefully!
    A2: Your address decoding might also indicate that there is more
        memory than really exists.  Go over your circuit design and
        inspect your wiring carefully.

    Q:  Can I use C for time critical code?
    A:  The code produced by many of the excellent compilers today, is
        remarkably efficient - for both speed and size.  Modern compilers
        are quite adept at keeping track of register and variable usage.
        Further optimization techiniques result in code that can be as
        good or better than hand written assembler.  Even for ISRs
        (interrupt service routines), C should be acceptable for all but
        the most time critical routines.

        However, don't think for a second that you can write haphazard C code and
        that the compiler will magically forgive your mess and make it efficient. In
        order to write efficient code for any microcontroller it is best to know the
        processor's programming model so you can make correct programming decisions.

    Q:  The Intel MCS-51 assembly language defines alternate symbols AR0
        ... AR7 for registers R0 ... R7.  What is this good for? (Thanks
        to Wolfgang Heinz who submitted this Q & A)
    A:  Some 8051 instructions do not support all possible addressing
        modes.  For example, the PUSH and POP instructions are only
        available with direct addressing. Since the registers R0 ... R7
        are mapped into the internal memory, they must also have a DATA
        (= direct) address.  The special assembler symbols AR0 ... AR7
        are simply the absolute DATA addresses of registers R0 ... R7.
        Although there is no instruction PUSH R5 with true register
        addressing, you can do it with PUSH AR5 (= direct addressing)!

    Q:  Usually the 8051 register banks are switched with the RS0 and RS1
        bits in the status register PSW at runtime.  But how is it
        possible to switch the banks at assembly time with the USING
        instruction, implemented in so many 8051 assemblers?
        (Thanks to Wolfgang Heinz who submitted this Q & A)
    A:  Not at all!  This must ALWAYS be done with bits RS0 and RS1 at
        runtime.  The USING instruction switches only the absolute DATA
        addresses of the special assembler symbols AR0 ... AR7 according
        to the selected bank number.  With most assemblers that implement
        relocatable segments and object modules, the linker is forced to
        reserve space for the corresponding register bank in the internal

    Q:  The Intel 8x151/8x251 won't "drop-in" for an 8051. What gives?
        (Thanks to Dave Baldwin of The Computer Journal for this one)
    A:  You need to use a programmer to set a couple bits to the correct
        state.  This info is hidden away in an app note available from
        their web site.

back to top


3.1)  FTP sites

    The following is a list of the various anonymous ftp sites that have
    8051 source code and programming languages.  There are many others
    that  are not listed here that contains bits and pieces.  Usually you
    can find them using Archie and searching for "8051", "AS31", "ASM51",
    "MCS-51", "MCS51", and stuff like that.

    ftp.pppl.gov (formerly lyman.pppl.gov)
        - this is a great source of 8051 stuff
        /pub/incoming - check this out for new untested/unsorted items

    ftp.funet.fi (nic.funet.fi)
        - this is a great one, too
        /pub/microprocs/MCS-51   <mirror of ftp.pppl.gov>
        other subdirectories in /pub/microprocs include:
          1802, 6805, 6811, 8048, 8096 and many other microprocessors

        - send comments to:  ftp-admin@intel.com
        /pub/mcs51/tools - contains various development tools

        - mirror of ftp.intel.com
        - /vendors/Intel


        - accepting uploads

    info@circellar.com - Email (not ftp)
        - send Email to get information file on services available
        - all Circuit Cellar INK and BYTE related files available

        - circuits of all types
        - prog51.zip is a programmer for the ATMEL 89C51 flash part
          by Werner Terreblanche


    asterix.inescn.pt - FORTH archive

        /mirrors/.hpib0/forth/8051 (mirror of asterix Forth archive)

    ftp.armory.com (Steve Walz)

        - has information and software for a wide range of
          microprocessors and microcontrollers, you may have to look
          around a bit

        - HiTech Equipment Corporation's ftp site
        - information about their products including some sample code,
          a free 8051 simulator, and various things from around the net
          that relate to the 8051 family

    csd4.csd.uwm.edu - no longer supports 8051, don't even try

3.2)  Web pages [updated 16-July-2000]

    Microcontroller.com (home of this FAQ)
       - http://Microcontroller.com
       - News, development tools info, supplier listings

    8052.com - Vault Information Services
       - http://www.8052.com
       - Tutorials and message board on 805x devices

    AM Research Web Site
        - http://www.amresearch.com/
        - Forth development systems and boards.

    Archimedes Software
        - http://www.archimedes.com/

    Chip Directories
        - http://www.hitex.com/chipdir           (USA, California)
        - http://www.leg.ufrj.br/chipdir         (Brasil)

    Chipmaker web page
        - https://Microcontroller.com/embedded/semiconductors.htm
        - contains URLs of major chipmakers

    Circuit Cellar Ink
        - https://www.circellar.com

    Dallas Semiconductor (now Maxim Integrated)
        - https://www.maximintegrated.com/
        - More Information on Maxim: https://www.wellpcb.com/Appetite-for-Acquisition-How-Maxim-Integrated-Bought-Its-Way-Into-the-NASDAQ-Top-100.html

    Emulation Technology
        - http://www.emulation.com
        - makes sockets

    FIG (Forth Interest Group) web site
        - http://www.forth.org/fig.html
        - http://www.forth.org/Forth/FAQ

    Forth, Inc.
        - http://www.earthlink.net/~forth
        - follow the links to chipFORTH, then to 8051

    Hi-Tech Software
        - http://www.hitech.com.au
        - demo C compiler available (limits - 1K size, no library source)

    Intel Resources
        - http://www.intel.com/design/
        - http://www.intel.com/design/usb/ (information on USB)

    Keil Software
        - http://www.keil./com
        - One of the most popular commercial 8051 C compiler suites available, supports all 8051 varients
        - demo version available

    Lakeview Research (Jan Axelson)
        - http://www.lvr.com/
        - microcontroller page (resources for 8052-Basic projects):

    Nohau Corporation  [updated 16-July-2000]
        - http://www.nohau.com/
        - Popular 8051 emulator manufacturer

    Paul's 8051 Tools, Projects and Free Code
        - http://www.pjrc.com/tech/8051/index.html  [updated 16-July-2000]
        - page contents: AS31 Assembler
                         PAULMON 8051 Family Monitor/Debugger
                         Low-Cost 8051 Development Board Designs
                         8051 Code Library
                         Atmel 89C2051 in-circuit programmer
    Phyton Corporation
        - http://www.phyton.com/  [updated 16-July-2000]
        - Easy-to-use low cost 8051 emulator with trace

    Poptronics Web page (Electronics Now, Popular Electronics)
        - http://www.poptronics.com/
        - current issue information, recent article related files, FTP
          site, subscription information

    The Polis research project web page
    - http://www-cad.eecs.berkeley.edu/Respep/Research/hsc/abstract.html
    - HW SW co-design web page

    Richard Grant's 8051 Based Vario
        - http://cougar.stanford.edu:7878/RGvario/vario.html
        - Hang-Gliding/Paragliding WWW server. The application is an
          8751 based variometer (used by pilots to indicate the rate of
          ascent or descent). It includes schematics and assembly
          language source.

    Systronix web site
        - http://www.systronix.com
        - Embedded Java

    Thomas Wedemeyer's SAB80C535 web page
        - http://www.zfn.uni-bremen.de/~g16i/
        - SAB80C535 based board design
        - English und German

    USB web page
        - http://www.usb.org/

    Xicor's web page
        - http://www.xicor.com/
        - 8051 microperipherals -

3.3)  Mailing lists

    (needs to be updated)

3.4)  BBSs

    (BBS Section Deleted July 2000 due to the web obsoleting them!)

3.5)  Help available!

    Listed here are individuals who have expressed interest in helping
    others with hardware and software problems for 8051 systems.

    Does any one else out there think that they can help?  Just let me
    know what your areas of specialization are and I'll add your name to
    the list.  Thanks!

    Dick Barnett <rbarnett@purdue.edu>
           voice: 765-494-7497
           snail: Richard H. Barnett, PE, Ph.D.
                  Professor of Electrical Engineering Technology
                  Purdue University
                  1415 Knoy Hall of Technology
                  West Lafayette, IN 47907-1415
       Specializes in 8051 (core processors), 80C552, and 87C751

    Mark Hopkins <mark@omnifest.uwm.edu>
       Mark is the author of the CAS assembler and of the 8051.ZIP
       programs.  He's now working on JOLT, a code generator with a
       C-like syntax.  His areas of specialization include:
       multitasking, interrupts, basic stuff (like addressing, memory
       spaces), the 8052 BASIC chip, interfacing the chip with external
       inputs and outputs

    Hans Schou <chlor@schou.dk>
       Hans is offering his assistance to users of the Standard
       Microsystems Corp. COM20051.  He's not an expert, but he has some
       experience with it.

    Neville Miles <nevm@scitec.com.au or nmes@ozemail.com.au>
       Applications and programming the Intel 8051.  He's also using
       Atmel parts if you need help with these.

    Steve <paxit@inetnebr.com>
       Steve has designed hardware and written software for the Atmel
       AT89C1051, Intel 87C52, and Philips 87C751, and has also built a
       programmer for the Atmel AT89C1051. He knows both hardware and

back to top

4)  8051 PRODUCTS

    This section includes descriptions and references to free and
    commercial software for the 8051.  FTP sites and BBSs contain many
    quality packages and code samples for free.  For heavy duty use, you
    might prefer the many commercial packages that are available.  With
    the public domain (or free) stuff, you're usually on your own.  The
    commercial packages usually provide extensive documentation and

4.1)  Free languages and development tools

    The following is a list of the languages and development tools that I
    could find on the net.  Nearly all of them include source code,
    however not all are public domain.


      Program: asem5112.zip
      Description: 8051 cross assembler for MS-DOS, freeware
      Author: W.W. Heinz
      Location: ftp.ix.de : /pub/elrad/023
                oak.oakland.edu : /SimTel/msdos/crossasm
                garbo.uwasa.fi : /pc/assembler

      Program: ML-ASM51.ZIP
      Description: MetaLink's 8051 family macro assembler
      Location:  ftp.pppl.gov : /pub/8051/signetics-bbs
                 ftp.funet.fi : /pub/microprocs/MCS-51/signetics-bbs

      Program: A51.ZIP
      Description: PseudoSam 8051 Cross Assembler
      Location:  ftp.pppl.gov : /pub/8051/signetics-bbs
                 ftp.funet.fi : /pub/microprocs/MCS-51/signetics-bbs

      Program: AS31.ZIP
      Description:  C source for an 8051 assembler, and a simple monitor
      Author:  Ken Stauffer
      Location:  ftp.pppl.gov : /pub/8051/signetics-bbs
                 ftp.funet.fi : /pub/microprocs/MCS-51/signetics-bbs
                 oak.oakland.edu : /pub/msdos/crossasm/as31.zip
                 many other locations (use Archie to find)

      Program: CUG292WK.ZIP
      Description:  C source for a cross assembler, includes 8051
      Author:  Alan R. Baldwin
      Location:  oak.oakland.edu : /pub/msdos/crossasm
                 pc.usl.edu : /pub/msdos/systools
                 many other locations (use Archie to find)

      Program: Frankenstein
      Description:  C source for a cross assembler, includes 8051
      Author:  Mark Zenier
      Location:  ftp.njit.edu : /pub/msdos/frankasm/FRANKASM.ZOO
                 lth.se : /pub/netnews/alt.sources/volume90/dec
                 ftp.uni-kl.de : /pub1/unix/languages/frankenstein.tar.Z
                 many other locations (use Archie to find)

      Program:  CAS 8051 assembler
      Description:  Experimental one-pass assembler for the 8051
                    with C-like syntax.  Includes assembler, linker
                    and disassembler.
      Author:  Mark Hopkins
      Location:  ftp.pppl.gov : /pub/8051/assem
                 ftp.funet.fi : /pub/microprocs/MCS-51/csd4-archive/assem

      Program:  a51
      Description:  Portable cross assembler (source in C), other
                    processors available
      Author:  William C. Colley, III
      Location:  hpcsos.col.hp.com : /misc/ns32k/beowulf/a-8051

      Program:  TASM
      Description:  Table driven cross-assembler for DOS, supports
                    many different microcontrollers and microprocessors
      Author:  Speech Technology Inc.
      Location:  various different places

      Program: HASM, HSIM
      Description: A configurable Makroassembler/Simulator
      Comment:  Only for private, educational, and evaluation use
                Only available in German
      Author: Dipl.- Ing. H.P. Hohe
      Location: ftp.ix.de:pub/elrad/022/hasm18.zip
                  and mirrors of ftp.ix.de

      Program:  as
      Description:  Portable cross assembler for (8051, TMS, PIC,
                    DSP5600, 68hc11).
      Comments:     Original version in German only. Turbo Pascal source
                    available for free. Unix version comes in source
                    form and is compilable in German or English.
      Author:  Alfred Arnold
      Location: ftp.uni-stuttgart.de : /pub/systems/msdos/programming/as
                  (original version in Turbo Pascal)
                  (new C version for Unix systems)


      Program:  BASIC52.ZIP (BASIC-52.ZIP)
      Description:  Source files for original BASIC 52 interpreter
      Author:  Intel Corporation, Embedded Controller Operations
      Location:  ftp.intel.com : /pub/mcs51
                 ftp.pppl.gov : /pub/8051/signetics-bbs
                 ftp.funet.fi : /pub/microprocs/MCS-51/signetics-bbs

      Program:  BAS051.ZIP
      Description:  Converts IBM BASIC to 8051 assembly (compiler)
      Author:  Winefred Washington
      Location:  ftp.pppl.gov : /pub/8051/signetics-bbs
                 ftp.funet.fi : /pub/8051/signetics-bbs

      Program:  BASIC31.ZIP
      Description:  BASIC-52 interpreter for 8031/8051 in external EPROM
      Author:  Intel w/ changes by Dan Karmann
      Location:  ftp.pppl.gov : /pub/8051/signetics-bbs
                 ftp.funet.fi : /pub/microprocs/MCS-51/signetics-bbs

      Program:  TB-51.ZIP
      Description:  TinyBASIC for 8031
      Author:  JHW (from Intel InSite library) w/ fixes by Tom Schotland
      Location:  ftp.pppl.gov : /pub/8051/signetics-bbs
                 ftp.funet.fi : /pub/microprocs/MCS-51/signetics-bbs

      Program:  TB51ML23.ZIP
      Description:  MetaLink ASM compatible tiny BASIC
      Author:  adapted for MetaLink assembler by Jim Lum
      Location:  ftp.pppl.gov : /pub/8051/signetics-bbs
                 ftp.funet.fi : /pub/microprocs/MCS-51/signetics-bbs


      Program:  EFORTH51.ZIP
      Description:  eFORTH environment for the 8051
      Author:  C. H. Ting
      Location:  ftp.pppl.gov : /pub/8051/signetics-bbs
                 ftp.funet.fi : /pub/microprocs/MCS-51/signetics-bbs
                 asterix.inescn.pt : /pub/forth/8051
                 hpcsos.col.hp.com : /mirrors/.hpib0/forth/eForth

      Program:  FORTH51.ZIP (FORTH86.ZIP used as host)
      Description:  FORTH development system for 8051 with PC host
      Author:  William H. Payne, the author of "Embedded Controller
               Forth for the 8051 Family"
      Location:  ftp.pppl.gov : /pub/8051/signetics-bbs
                 ftp.funet.fi : /pub/microprocs/MCS-51/signetics-bbs
                 asterix.inescn.pt : /pub/forth/8051
                 hpcsos.col.hp.com : /mirrors/.hpib0/forth/8051

      Program:  XD8051.ZIP
      Description:  Development environment for use with F-PC Forth
      Author:  Paulo A.D. Ferreira
      Location:  ftp.pppl.gov : /pub/8051/signetics-bbs
                 ftp.funet.fi : /pub/microprocs/MCS-51/signetics-bbs

      Program:  51FORTH.ZIP
      Description:  Subroutine threaded Forth
      Author:  Scott Gehmlich
      Location:  hpcsos.col.hp.com : /mirrors/.hpib0/forth/8051
        : /giovanni/51forth.zip

      Program:  FORTH552.ZIP
      Description:  A Non-Standard Forth System for the Signetics 80C552
      Author:  Alberto Pasquale
      Location:  asterix.inescn.pt : /pub/forth/8051
                 hpcsos.col.hp.com : /mirrors/.hpib0/forth/8051

      Program:  CamelForth/51
      Description:  ANSI Standard Forth for the 8051 family
      Author:  Brad Rodriquez
                  email: bj@headwaters.com
                  amateur packet radio: VE3RHJ@VE3IJD.#CON.ON.CAN.NA
      Location: ftp://ftp.taygeta.com/pub/Forth/Camel/cam51-13.zip

      Program:  8051 eForth
      Description:  Public Domain optimized eForth for 8051 and 68HC11,
                    written in native UCASM assemblers.
      Comments:  Most of the documentation is in German.  Supplied with
                 EFTERM terminal emulator.
      Author:  W. Schemmer
      Location:  Available for $25 from:
                 Offete Enterprises, 1306 South B Street
                 San Mateo CA 94402

    Development systems

      Program:  8051.zip
      Description:  Many development tools including: debugger, monitor,
                    LCD and stepper moter driver, communications, host
                    client, and much more.  This is a great collection of
      Author:  Mark Hopkins
      Location:  ftp.pppl.gov : /pub/8051/signetics-bbs
                 ftp.funet.fi : /pub/microprocs/MCS-51/csd4-archive

      Program:  RISM and IECM51.EXE compatible host system
      Description:  RISM is a reduced instruction set monitor and
                    IECM51.EXE is its compatible host system for a PC
      Comments:  These two programs together constitute a bare-bones
                 method of developing 80C51 system code without an
                 emulator.  RISM51X is installed in the target system
                 and connected to a host PC system through a serial port.
                 The host PC runs the debugger IECM51.EXE.  Once the
                 system has been debugged, RISM can be removed and the
                 target can be run in stand-alone mode.
      Author:  Intel
      Location:  ftp.intel.com : /pub/mcs51/tools

      Program:  ApBUILDER 2.0
      Description:  Development system for the Intel MCS-51(R) family
                    (also for the MCS-96(R) family, 80x186, and 80x386
                    embedded microcontrollers).
      Comments:  Requires Windows 3.1
                 APBUILDR.TXT - description in ASCII
                 APBDISK1.EXE - binary self-extracting file for disk 1
                 APBDISK2.EXE - binary self-extracting file for disk 2
      Author:  Intel
      Location:  ftp.intel.com : /pub/mcs51 and /pub/mcs96

      Program:  FXDSMAN.EXE
      Description:  8xC51Fx data sheets and manual in Windows 3.1
                    hypertext style
      Comments:  binary self-extracting file for one diskette
      Author:  Intel
      Location:  ftp.intel.com : /pub/mcs51/80c51

      Program: sim51d
      Description:  Shareware Simulator in German
                    DM 50 to register for full version
      Author:  Werner Hennig-Roleff
      Location:  ftp.pppl.gov : /pub/8051/hannover

      Program: PDSWxxx.ZIP (where xxx represents the version number)          [updated 17-July-2000]
      Description: This is the 32-bit Windows IDE for PDS51, the Philips 80C51 and LPC family
                   emulation system. Can also be run as a simulator.
                   Supports all major compiler and assembler vendors.
      Location: http://www.pds51.com

      Program: NoICE
      Description:  PC-hosted debugger (NOT a simulator) for use with a
                    variety of microprocessor targets (Z80/Z180, Z8,
                    8051, 80(1)96, 6809, 68HC11, 65(C)02, M50740/M38000,
                    TMS370, and H8/300). The debugger consists of a
                    target-specific DOS program, NOICExxx.EXE, and a
                    target-resident monitor program (about 1K code).
      Comments:  Shareware.  The distributed version is fully functional.
                 Registration is $25 in the US, $30 elsewhere.
      Author:  John Hartman <102203.1513@compuserve.com>
      Location: any Simtel archive/mirror
                   GO SDFORUM, library section 12, embedded systems
                   GO IBMFF, do keyword search for "NoICE"
                The Circuit Cellar BBS at 860-871-1988

      Program: sim552vq.zip
      Description:  8051/80C552 simulator (Freeware)
      Comments:  Program is capable of reading .HEX and .S19 records, or
                 saving memory to a file.  It supports both code and
                 data.  Written in Turbo Pascal for XT and upwards.
      Author:  Brian Brown
      Location:  cscnt.cit.ac.nz : /pub/intel/sim552v1.zip

      Program: HASM, HSIM
      Description: A configurable Makroassembler/Simulator
      Comments: Only available in German
      Author: Dipl.- Ing. H.P. Hohe
      Copyright: Only private , Education and evalutation use
      Location: ftp.ix.de:pub/elrad/022/hasm18.zip
                  and mirrors of ftp.ix.de

      Program: Emily52
      Description:  simulator
      Comments:  Shareware.
      Author:  Dunfield Development Systems
      Location: any Simtel archive/mirror

      Program: BlowIT
      Description:  Atmel 2051 programer
      Comments:  Freeware
      Author:  Silicon Studio
      Location: http://sistudio.com/

    Real-Time Operating Systems (RTOS)

      Program:  TERSE
      Description:  - Signature-Scheduled dataflow operating system
                    (RTOS) developed for embedded single-processor and
                    distributed microcontroller systems.  Easy to use,
                    very compact, and encourages totally deterministic
                    and safe performance.
                    - The first implementation is for the 8051 family,
                    and occupies from 260 to 450 bytes, the latter
                    offering network support.
                    - public domain
      Comments:  Also available is a new type of "terse-Case" development
                 methodology, particularly suited to embedded distributed
      Author: Barry Kauler
              Department of C & C Engineering
              Edith Cowan University, Joondalup Drive
              Joondalup, WA 6027, Australia.
              Email: b.kauler@cowan.edu.au
      Location:  WWW - http://www.goosee.com

4.2)  Free C compilers

  * Small Device C Compiler SDCC http://sdcc.sourceforge.net/  [text supplied by SDCC 16-July-2000]
    SDCC is a freeware, retargettable, optimizing ANSI - C compiler, that runs on Linux and MS Windows 95/98/NT.
    SDCC will compile natively on Linux using gcc.  Windows users will need to download the full development
    version of CYGWIN32, or download a pre-built WIN32 binary.

    SDCC was originally written by Sandeep Dutta, and the entire source code for the compiler is distributed
    under GNU General Public License.  Since its release, many others have contributed to SDCC's development.
    The code is hosted by SourceForge where all the "users turned developers" can access the same
    source tree.

    SDCC supported data types are short (8 bits, 1 byte), char (8 bits, 1 byte), int (16 bits, 2 bytes ),
    long (32 bit, 4 bytes) and float (4 byte IEEE). SDCC also comes with the source level debugger SDCDB.
    The compiler also allows inline assembler code to be embedded anywhere in a function. In addition routines
    developed in assembly can also be called.

    SDCC has extensive MCU specific language extensions which lets it utilize the underlying hardware
    effectively.  In addition to the MCU Specific optimizations SDCC also does a host of standard
    optimizations, including global sub expression elimination, loop optimizations (loop invariant, strength
    reduction of induction variables and loop reversing), constant folding and propagation, copy propagation,
    dead code elimination and jump tables for 'switch' statements.  For the back end SDCC uses a global
    register allocation scheme which should be well suited for other 8 bit MCUs, the peep hole optimizer uses
    a rule based substitution mechanism which is MCU independent.

  * The Retargetable Concurrent Small C (RCSC) compiler is a free C compiler  [updated 16-July-2000]
    for the 8051. RCSC is downloadable from Dr. Dobb's at the ftp directory ftp://ftp.ddj.com/1997/1997.08/
    You want the files rcsc.asc, which gives a few examples, and rcsc.zip (691K), which is the actual
    compiler archive.

    Most commercial C compilers have evaluation versions available.
    These are not too useful (even for hobbyist projects) since they
    usually don't include libraries.  However, they do afford the user
    the chance to inspect the quality of the code generated.

    In most cases, it makes more sense to invest a bit, and get something
    serious.  Also, by buying a commercial package, you have the
    advantage of having the documentation, and being able to get
    technical support.  As Hershel Roberson says about the Dunfield
    package, "It is certainly worth the money. It is probably 3/4 as good
    as compilers that cost 10 times as much!"

    There are three low-cost C compilers currently available for 8051

    Dunfield Development Systems

    I've been using the Dunfield Development System, and its really quite
    nice.  I've also heard many good things about it from others.  For
    $100 you get a near ANSI-C compiler, run-time library with source,
    assembler, ROM debugger, integrated development environment, monitor
    with source, utilities, and other extras.  A high quality simulator
    for only $50 is also available separately.  The simulator has an
    option allowing you to interface to your target by using an on-chip
    monitor.  Although not freeware, the low price, the features, all of
    the extra goodies, and the good reviews make this a package worth
    looking at.  Also, if you're interested in working on more than one
    family of microcontroller, Dunfield supports a wide range.  This
    means only needing to learn one system, instead of many.

          Dunfield Development Systems
          P.O. Box 31044, Nepean, Ontario Canada   K2B 8S8
          (613)256-5820   Fax: (613)256-5821
          BBS: (613)256-6289
          Web:   http://www.dunfield.com
          Email: General information:      info@dunfield.com
          Sales inquiries/Administration: sales@dunfield.com
          Technical inquiries/Support      tech@dunfield.com

    Micro Computer Control Corporation

    Another low priced ($100) C compiler comes from Micro Computer
    Control.  This package was unavailable for review, but according to
    the manufacturer, it features:  Cross compilers running under DOS are
    available for the 8051 and the Z8 (including Super-8).  This package
    includes a C compiler, assembler, linker, librarian, and extensive
    printed documentation.  A simulator/source code debugger is available
    for an additional $79.95.  The simulator is completely configurable,
    so much so that you don't even need the target hardware to test with.
    You can configure all I/O and other features of your target chip or

          Micro Computer Control Corporation
          PO Box 275, 17 Model Ave., Hopewell, NJ  08525
          (609)466-1751   Fax: (609)466-4116   BBS: (609)466-4117
          Email: 73062.3336@compuserve.com

    SPJ Systems

    C-31 is a cross compiler from SPJ Systems.  The full package is not free,
    but only costs $150 (USD). It includes a C compiler (ANSI compatible subset),
    assembler, source linker, and simulator (source code debugger).  Compiler features
    include: support for floating point numbers, extensive collection of library
    routines, support for using Special Function Registers (SFR), assembly language
    interface, peripheral keyword (allows specifying an address of a standard

    The simulator allows source level debugging.  A few memory mapped hardware peripherals
    are simulated including an LCD display, 8279 keyboard processor, and an 8255 parallel
    port.  (SPJ also has a plain simulator available as a separate product for
    assembly/machine code debugging.)

    A working demo of the compiler package, which includes the library sources and permits
    the compilation of small programs, is available from their web site.  This is a new
    package with a few rough edges, but it easy to use, has a decent price, and has
    good potential. Check out the demo on their web site and see for yourselves.

          SPJ Systems
          114, Chitrashala Bldg.
          562, Sadashiv Peth
          Pune, India
          Phone: 91-20-4451607   Fax: 91-20-4480285
          Email: spj@spjsystems.com
          Web:   http://www.spjsystems.com

4.3)  Commercially available products

    Many firms (large and small) offer a variety of 8051 microcontroller
    variants, programming languages, support packages, and development

    No endorsement is implied by inclusion in this list.  I apologize to
    anyone I left out;  It's only because I didn't know about you.  If
    you want to be included in this list, just drop me a line - please.
    Any corrections and additions appreciated.

    C compilers ($$$ - high, $$ - medium, $ - low priced)  24-Jan-2000
        - 2500 A.D.
        - Archimedes Software  $$$ & $$
        - Avocet Systems  $$
             repackaging of the Hi-Tech Software C compiler
        - ByteCraft $
        - Crossware Products
        - Dunfield Development Systems  $
             Complete C compiler development system for MS-DOS
             includes: compiler, run-time library with source, assembler,
                ROM debugger, integrated development environment, monitor
                with source, utilities, and other extras
             low price:  $100
             good reputation and good support
             works well with the Dallas DS5000/DS2250
        - Franklin Software  $$ ? (new prices)
             now marketing their own C compiler
             includes: PC-Lint and an IDE
        - IAR Systems
             IAR tool kit comes with a C-Cross compiler, assembler,
                Xlink linker, Xlib librarian, C-SPY simulator, editor,
                make utility and a real-time kernel
             formerly licensed for distribution in the US and Canada
                under the Archimedes brand name
        - Hi-Tech Software  $$
             assembler, C compiler, linker, library, serial port
                debugger, and Windows style integrated development
             ANSI C and IEEE 32 float compatable with some very useful
        - Intermetrics Microsystems Software, Inc.
             Whitesmith's compiler, assembler, and C source level
        - Keil Software  $$$
             compiler, assembler, debugger, real-time kernel, ROM
                monitor, libraries for special 8051's to set SFR,
                embedded I/O devices, A/D, etc. One of the most popular
                8051 compilers on the market today. Also has USB and
                CAN support.
        - Mandeno Granville Electronics, Ltd
             SYS51C - ANSI C Cross Compiler
        - Micro Computer Control  $
             Developer's kit includes "C"-like compiler, assembler,
                linker, librarian, extensive printed documentation
             low cost ($99.95)
        - Okapi Systems
        - Production Languages Corporation
             DOS- and Windows- based compilers
             Integrated development environment includes ANSI C compiler,
                assembler, linker, librarian, debugger
        - Raisonance
          32-bit Windows assembler/compiler/linker and IDE for 8051 and XA. Also
          supports ST-Microelectronics ST6 8-bit microcontroller.
        - Signum Systems
        - SPJ Systems  $
             low cost ($150.00)
             Includes compiler, linker, simulator
        - Tasking Inc. Also has USB support $$

    BASIC Interpreters/Compilers
        - Binary Technology, Inc.
        - Blue Earth Research: Blue Earth offers a BASIC interpreter based on the Intel BASIC-52 source.
          A tiny BASIC interpreter is also available. They are enhanced to be specific to the controller
          boards that they sell. A BASIC compiler is also available.
        - MDL Labs
             BASIKIT--Integrated Programming Environment for BASIC-52,
                and for MDL-BASIC-I, MDL-BASIC-P, and MDL-BASIC-D.
    BASIKIT includes a full-screen editor and permits writing
                programs with labels rather than line numbers.
             MDL-BASIC-I and MDL-BASIC-P are supersets of the original
                BASIC-52, for the Intel 8052 and the Philips PCB83C552.
             MDL-BASIC-D is a BASIC for the Dallas 87C530 which accesses
                all the features of the chip, including both serial
                ports, the Watchdog, and the power-saving features. The
                BASIC will address up to 512K of memory and will collect
                data into that memory via serial port interrupts. It runs
                faster at 25 MHz than compiled code on the 8052.
        - Micro Future
             Basic-52 development system
        - Systronix Inc. (Basic compiler)

    Pascal (no kidding!)
        - Mandeno Granville Electronics, Ltd
             PASCAL51 - Advanced Turbo PASCAL compliant cross compiler
        - Scientific Engineering Labs
        - Embedded Pascal - a low-cost integrated Pascal environment for the 8051

        - Mandeno Granville Electronics, Ltd
             Mod51 - optimizing Modula-2 Compiler, smallest program is 14
             bytes, ideal for both very tight/fast projects and very
             large ones with multiple modules, produces smaller/tighter
             code than C, has extensive libraries and working examples
        - Vail Silicon Tools, Inc.

    Board level products
        - Ackerman Computers Sciences (ACS)
        - AM Research
             complete FORTH based system with PC based host system
        - Binary Technology, Inc.
        - Blue Earth Research
        - Blue Ridge Micros (8031 and 8052-BASIC based boards)
        - CG Microsystems
             MCU system based on the DS80C320
             piles of features including 2 ISA slots
             about $90 for the basic system
        - Circuit Cellar Inc.
        - DataCraft International
        - Dunfield Development Systems
        - EE Systems
        - Forth, Inc.
        - HiTech Equipment Corp.
        - J & M Microtek, Inc.
        - L.S. Electronic Systems Design
        - Mandeno Granville Electronics, Ltd
        - New Micros
             8051 based NMIY0031 SBC
             $39 + shipping you
             includes: SBC with 8051 (Infineon SAB8051, can be
                substituted), 8K RAM, EPROM with a burnt-in monitor which
                supports downloading hex files into the RAM and executing
             the board can accept 3 memory chips (each one up to
                32K), one of which is for program, one for data and the
                third can be configured as wanted
             it has a 4x5 matrix keyboard interface, LCD interface,
                RS232 and support for RS422/485 (need to add the chips)
    prototyping area of about 3.5 x 2 inches
             on floppy you get:  User manual for the board in Word
                and plain text formats with many programming examples in
                all supplied languages (about 150 pages), A51 assembler,
                Small C compiler, hex file for the MCS-52 Basic
                interpreter EPROM with MCS-52 manual, hex file for
                MAX-FORTH interpreter EPROM with documentation, hex file
                for the supplied monitor and documentation, and a
                terminal program
        - Parallax, Inc.
        - Prologic Designs
        - Rigel Corporation
        - Software Science
             nice boards with prototyping area
        - Suncoast Technologies
        - URDA, Inc.

        - 2500 A.D.
        - 8052.com
        - Archimedes Software
        - Crossware Products
        - Custom Computer Consultants
        - Cybernetics Microsystems
        - Dunfield Development Systems
             Supports both Intel and Motorola style syntax
        - Emulation Technology, Inc.
        - Intel Corporation
        - Keil Software
        - Metalink
        - Micro Computer Control
        - Microtek Research
        - Onset Computer Corporation (8051 Assember for MAC)
        - PseudoCorp
        - Phyton, Inc
        - Raven Computer Systems
        - Signum Systems
        - Speech Technology Inc.
             TASM (table driven cross assembler supports many different
             microcontrollers and microprocessors)
        - Universal Cross Assemblers
             CROSS32 supports 40-50 different processors
        - Tasking

        - AM Research
             Development system, features kernel of less than 700 bytes
        - Forth, Inc.
             A cross-development product for the 8051 family
                which includes a board and extensive documentation.
        - Forth Systeme
        - MPE: MicroProcessor Engineering Ltd.
             A cross-development system for the 8051 family
                extensive documentation
             interactive single chip development, multitasking,
                bank switching for more than 64k code
        - Offete Enterprises
             8051 eForth (C. H. Ting -- $25.00).  "A small ROM based
                Forth system ... Source code is in MASM IBM 5.25 disk
                with 8051 eForth Implementation Note."

    ROM Monitor-based Debuggers
        - ChipTools (ChipView-51 looks like turbo debugger)
        - Dunfield Development Systems
             Can be used with DS5000 for single-chip in-circuit

    Simulators  24-Jan-2000
        - 8052.com
        - Archimedes
        - Avocet Systems
        - ChipTools, Inc.
        - Crossware (simulator running under Windows)
        - Dunfield Development Systems
             Low cost $50.00
             500,000+ instructions/second on 486/33
             Can interface to target system for physical I/O
             Includes PC hosted "on chip" debugger with identical user
        - HiTech Equipment Corp.
        - Hitex
        - J & M Microtek, Inc.
        - Keil Software
        - Lear Com Company
        - Mandeno Granville Electronics, Ltd
        - Micro Computer Control Corporation
             Simulator/source code debugger ($79.95)
        - Microtek Research
        - Phytec
        - Phyton
        - Production Languages Corp.
        - PseudoCorp
        - SoftChip Ltd
        - Tasking Inc.

    Emulators ($$$ - high, $$ - medium, $ - low priced)
      Check to make sure that the emulator supports the required
      peripherals (UART, SPI, etc), as well as you memory configuration,
      before you make your selection.
      emulator supports the required external hardware (ports,
      interrupts, etc) before they buy - its probably the most
      important spec, but one easily missed. Some emulators only offer
      very minimal support, which sometimes hardly makes it worthwhile to
        - Advanced Micro Solutions  $$
        - Advanced Microcomputer Systems, Inc.  $
        - Acqura Systems (formerly Applied Digital Research Ltd.)  $$
        - American Automation  $$$  $$
        - Applied Microsystems  $$
        - ChipTools (front end for Nohau's emulator)
        - Cybernetic Micro Systems  $
        - Dunfield Development Systems $
        - HBI Limited  $
        - Hitex  $$  $$$
        - Huntsville Microsystems  $$
        - Intel Corporation  $$$
        - Lauterbach Datentechnik GmbH $$$
             8051 In-Circuit Emulators based on a universal high-
                performance emulation system called TRACE32.
        - Mandeno Granville Electronics, Ltd
             full line covering everything from the Atmel flash to the
                Infineon powerhouse 80c517a
        - MetaLink Corporation  $
        - Nohau Corporation  $$
        - Phytec Corporation $
        - Signum Systems  $$
        - Sophia Systems  $$$
        - Zax Corporation
        - Zitek Corporation  $$$

        - Byte-BOS Integrated Systems
             small, prioritized, preemptive real-time kernel
        - Embedded System Products (formerly A.T. Barrett and Associates)
             ROMable embedded-system kernel: source provided.  Provides
             programming interface identical on all target platforms.
             Basic, advanced, and extended library packages available.
        - Intellimap Engineering
             DCE51 real time operating system
        - JMI Software Systems, Inc.
             small, prioritized, preemptive real-time kernel
        - StarCom
             CRTX, embedded real-time micro kernel primarily intended for
             embedded 8-bit applications using 8051, 68HC11, 80188 etc.
             Simple, low cost, and includes ANSI C source for
        - U S Software
             SuperTask! - multitasking executive

        - Advanced Educational Systems (AES)
             complete learning system (board, LCD, keypad, A/D, D/A, etc)
        - Sun Equipment Corp.

        - Creative Applications Engineering, Inc
             CheepTools (integrated environment)
        - Dallas Semiconductor
             evaluation/development kit for their DS5000 (very nice)
        - Data Sync Engineering (disassembler)
        - Datarescue
             IDA - an interactive, multi-os disassembler supporting:
             OS/2, Win95, Win NT, Win, NLMs and more. Unlike other
             disassemblers, IDA works with you, allowing you to modify
             the disassembled code "on the fly". It supports many
             processors, various input file formats, and can produce
             various output files etc.  IDA has a built-in C-like
             language and sports a TVision user interface.
        - Educational Laboratories
             development courses:
               8051 Microcontroller Based Computer Design
               Programming 8051 Based Computers
             each course $19.95, both $29.95
        - Electronic Product Design, Inc.
             development system (integrated package with assembler,
             project manager, text editor, programmer)
        - Exor Inc. (ladder logic compiler)
        - Feger + Co.
             offers a series of German language 8051 related books they
             call `MC-Tools' describing the processors and/or projects
             for PC-addin boards:
             MC-Tools 1 - 80c535 project for DM 119; includes 260 page
               book, an empty PCB, and a diskette with assembler,
               debugger, PC-Oscilloscope
             MC-Tools 4 - same as above but based on 80c537
             MC-Tools 3 - Die 8051-Microcontroller Familie vom 8051 zum
               80C517A; text book on the 8051 and Infineon derivatives,
               360 pages.
             MC-Tools 5 - handbook on the 80C517 and 80C517A, 360 pages
        - Mandeno Granville Electronics, Ltd
             PIC to 8051 conversion program
        - Philips
             87C51 programmers
               LCPx5x - 24 and 28 pin DIL and 68 pin PLCC Philips parts
                      - 748, 749, 750, 751, 752, 451, 453, 552
               LCPx5x40 - 40 pin DIL or 44 pin PLCC Philips parts
               Range further expanded by adaptors
        - Quantasm Corp.
             ASMFLOW - produces flowchart and tree diagrams from source
                code, register usage analysis, Xref, timing info
        - TCG
             EPROM emulator
             Atmel 2051 programmer
        - U S Software
             USNET - TCP/IP networking suite
             USFiles - file system
             GOFAST - floating point library
        - Xicor
             SLIC2E microperipherals - wires up directly to an 8051 and
               needs no glue logic, contains:
                  - 8K x 8 EEPROM in individual 4K segments
                  - 2 8-BIT I/O ports
                  - 16 8-BIT RAM registers
                  - Integrated Interrupt Controller Module
                  - Internal programmable address decoding
                  - code loaded at the factory allowing users to
                    download programs into EEPROM
             Development Support package includes a DATA BOOK, a
               SAMPLE of the CHIP (PDIP or PLCC, your choice) and PC
               compatible software for downloading and testing your
               programs. $15
             Development system includes a populated board. $180

    2500 A.D.       109 Brookdale Ave., Box 480, Buena Vista, CO  81211

    Ackerman Computer Sciences (ACS)
                    4276 Lago Way, Sarasota, FL  34241
                    (813)377-5775   Fax: (813)378-4226

    Advanced Educational Systems (AES)
                    1407 North Batavia Street, Orange, CA  92677
                    (800)730-3232   (714)744-0981   Fax: (714)744-2693

    Advanced Micro Devices
                    901 Thompson Place, PO Box 3453
                    Sunnyvale, CA  94088-3000

    Advanced Microcomputer Systems, Inc.
                    1321 NW 65th Place, Fort Lauderdale, FL 33309
                    (305)975-9515  Fax: (305)975-9698

    Advanced Micro Solutions
                    1033 S Imperial Dr., Hartland, WI 53029

    American Automation
                    2651 Dow Avenue, Tustin, CA  92680

    AM Research     4600 Hidden Oaks Lane, Loomis, CA  95650
                    (800)949-8051   (916)652-7472   Fax: (916)6642
                    BBS: (916)652-7117
                    Email: support@amresearch.com

    Acqura Systems
                    P.O. Box 6480, Wellesley St, Auckland, NEW ZEALAND
                    +64 9 415-2514, Fax +64 9 415-3514
                    Email: info@acqura.com
                    WWW: http://www.acqura.com

    Applied Microsystems
                    5020 148th Ave. N.E., PO Box 97002
                    Redmond, WA  98073-9702

    Archimedes Software
                    2159 Union St., San Francisco, CA  94123
                    WWW: http://www.archimedes.com/devtools

    Ashling Microsystems Ltd
    Ireland         Plessey Technological Park
                    Limerick, Ireland
                    +353 61 334466   Fax:  +353 61 334477
    United Kingdom  Butler House
                    19-23 Market Street
                    Maidenhead, Berkshire,  UK
                    +0628 773070   Fax: 0628 773009

    Atmel           2125 O'Nel Drive, San Jose, CA  95131
                    (800)365-3375  (408)441-0311   Fax: (408)436-4300

    Avocet Systems  120 Union St., Rockport, ME  04856
                    (800)448-8500  (207)236-9055   Fax: (207)236-6713

    Binary Technology, Inc.
                    PO Box 541, Carlisle, MA  01741
                    (508)369-9556   Fax: (508)369-9549

    Blue Earth Research
                    1415 First Ave Suite 400, Mankato, MN 56001
                    (507)387-4001   Fax: (507)387-4008

    Blue Ridge Micros
                    2505 Plymouth Rd., Johnson City, TN  37601
                    (615)335-6696   Fax: (615)929-3164

    United States   333 Elm Street, Dedham, MA  02026-4530
                    (800)458-8276  (617)320-9400  Fax: (617)320-9212
    Europe          Tasking Software BV
                    P O Box 899, 3800 AW Amersfoort, Netherlands
                    +31 33 558584   Fax: +31 33 550033

    Business Data Computers
                    P.O. Box 1549, Chester, CA  96020

    Byte-BOS Integrated Systems
                    P.O. Box 3067, Del Mar, CA 92014
                    (800)788-7288   (619)755-8836

    CG Microsystems

    ChipTools Inc   (905)274-6244   Fax: (905)891-2715
                    Email: Email: info@chiptools.com
                    Web: http://www.chiptools.com/

    Circuit Cellar Inc.
                    4 Park St., Vernon, CT  06066
                    (203)875-2751   Fax: (203)872-2204

    Creative Applications Engineering, Inc
                    Ed Carryer
                    (415)494-2363   BBS: (415)494-8463

    Crossware Products
                    St John's Innovation Centre
                    Cowley Road, Cambridge, CB4 4WS, UK
                    +44 1223 421263  Fax: +44 1223 421006
                    Email: sales@crossware.com
                    Web: http://www.crossware.com

    Custom Computer Consultants
                    1807 Huron River Drive, Ypsilanti, MI 48197

    Cybernetic Micro Systems
                    Box 3000, San Gregorio, CA  94074

    Dallas Semiconductor
                    4401 S. Beltwood Parkway, Dallas, TX  75244-3292
                    (214)450-0448   Fax: (214)450-3715
                    International:  (214)450-5351
                    Orders:  (800)336-6933
                    Email: micro.support@dalsemi.com
                    Web: www.dalsemi.com

    DataCraft International
                    2828 Ione Dr., San Jose, CA  95132
                    (800)873-3709   (408)259-4866

    Data Sync Engineering
                    40 Trinity St., Newton, NJ 07860
                    (201)383-1355   Fax: (201)383-9382
                    Email: sales@datasynceng.com
                    Web: http://www.datasynceng.com

    DataRescue sprl
                    110 route du Condroz, 4121 Neupre  Belgium
                    Web: http://www.datarescue.com

    Dunfield Development Systems
                    P.O. Box 31044, Nepean, Ontario Canada   K2B 8S8
                    (613)256-5820   Fax: (613)256-5821
                    BBS: (613)256-6289
                    Web:   http://www.dunfield.com
                    Email: General information:      info@dunfield.com
                    Sales inquiries/Administration: sales@dunfield.com
                    Technical inquiries/Support      tech@dunfield.com
                    Old Email address:  ddunfield@bix.com

    EE Systems      50935 Hill Dr., Elkhart, IN  46514
                    (219)296-1754   Fax: (219)522-4271

    Electronic Product Design, Inc.
                    6963 Bluebelle Way, Springfield, OR  97478

    Embedded System Products (formerly A.T. Barrett and Associates)
                    11501 Chimney Rock, Houston, TX  77035-2900
                    (800)525-4302   (713)728-9688   Fax: (713)728-1049

    Emulation Technology, Inc.
                    2344 Walsh Avenue, Bldg. F, Santa Clara, CA  95051
                    (408)982-0660   Fax: (408)982-0664
                    Email: et@pmail.emulation.com
                    WWW: http://www.emulation.com
                    FTP: ftp.emulation.com

    Exor Inc.
                    4740T Interstate Dr., Cincinnati, OH 45246
                    (513)874-4665   Fax: (513)874-3684

    Feger + Co., Hardware + Software Verlags OHG
                    Marienstrasse 1, D-83301 Traunreut, Germany

    Forth, Inc.     1-800-55FORTH

    Forth Systeme   P.O. Box 1103, Breisach, Germany

    Franklin Software

    HBI Limited
                    6F, 1 Fleming Road, Hong Kong
                    852-891-3673  Fax: 852-834-9748

    Hewlett-Packard 1501 Page Mill Rd., Palo Alto, CA  94304

    HiTech Equipment Corp.
                    9672 Via Excelencia, San Diego. CA 92126
                    (619)566-1892   Fax: (619)530-1458
                    Email: info@hte.com   WWW: http://www.hte.com

    Hi-Tech Software
                    PO Box 103, Alderly QLD 4051, Australia
                    (+61-7) 300 5011   Fax: (+61-7) 300 5246
                    BBS: +61 7 3300 5235
                    Email: hitech@hitech.com.au WWW: http://www.hitech.com.au/

    North America   HiTOOLS Inc., 2055 Gateway Place, Suite 400
                    San Jose, CA 95110
                    (408) 451 3986   Fax: (408) 441 9486
                    http://www.hitex.com  info@hitex.com
    Germany         Greschbachstr 12, 76229 Karlsruhe
                    0721/9628-0      Fax: 0721/9628-149
    United Kingdom  Sir William Lyons Road, Science Park
                    Coventry CV4 7EX
                    +0203 692066     Fax: +0203 692131

    Huntsville Microsystems
                    4040 S. Memorial Parkway, PO Box 12415
                    Huntsville, AL  35802

    IAR Systems Software
    North America   One Maritime Plaza, Suite 1770
                    San Fransisco, CA 94111  USA
                    (415)765-5500   Fax: (415)765-5503
    Sweden          IAR Systems AB
                    Box 23051
                    S-750 23 Uppsala, Sweden
                    +46 18 16 7800   Fax: +46 18 16 7838
    Germany         IAR Systems GmbH
                    Brucknerstrasse 27
                    D-81677 Munchen, Germany
                    +49 89 470 6022   Fax: +49 89 470 9565
    United Kingdom  IAR Systems Ltd
                    9 Spice Court
                    Plantation Wharf, York Rd
                    London SWII 3UE, England
                    +44 71 924 3334   Fax: +44 71 924 5341

    Intel Corporation
                    3065 Bowers Ave., Santa Clara, CA  95051
                    Technical Help: (800)628-8686 (USA/Canada only)
                       5 am to 5 pm PST
                    Email: james_sampson@ccm.hf.intel.com
                    Faxback support: (800)628-2283 (USA/Canada)
                       touch tone phones only
                       Will only FAX to USA/Canada locations
                       English or Japanese support is available
                    BBS: (916)356-3600  24 Hr.
                       Auto config: 1200 thru 14.4K Baud

    Intellimap Engineering
                    1140 Morrison Dr., Suite 222
                    Ottawa Ontario Canada K2H 8S9
                    (613)829-3196   Fax: (613)820-1773

    Intermetrics Microsystems Software, Inc.
                    733 Concord Ave., Cambridge, MA  02138
                    (617)661-0072   Fax: (617)868-2843

    Integrated Silicom Solution
                    2231 Lawson Lane, Santa Clara, CA  95054
                    (800)379-4774  Fax: (408)588-0806

    J & M Microtek, Inc.
                    83 Seaman Rd., W Orange, NJ  07052
                    (201)325-1892   Fax: (201)736-4567

    JMI Software Systems, Inc.
                    P.O. Box 481, 904 Sheble Lane, Spring House, PA 19477
                    (215)628-0840   Fax: (215)628-0353

    KC Automation GmbH (support for Sysoft products)
                    Alfredo Knecht
                    CH-6991 Neggio, Switzerland
                    Fax: ++41-91591149
                    Email: akne@tinet.ch

    Keil Elektronik GmbH
      Europe        Bretonischer Ring 15
                    D-85630 Grasbrunn b. Muenchen, Germany
                    49 89 / 46 50 57   Fax: 49 89 / 46 81 62

      North America Keil Software
                    1501 10th Street, Suite 110
                    Plano, TX  75074
                    (800)348-8051 (sales and tech support)
                    (972)312-1107   Fax: (972)312-1159
                    Also has an extensive web support Knowledge Base
                    Web: http://www.keil.com/
                    FTP: ftp://ftp.keil.com/

    Lakeview Research (Jan Axelson)
                    2209 Winnebago St., Madison, WI  53704
                    Email: jaxelson@lvr.com
                    WWW: http://www.lvr.com/

    Lauterbach Datentechnik GmbH
      Europe        Fichtenstr. 27, D-85649 Hofolding, Germany
                    ++49 (0)8104 8943 31   Fax: ++49 (0)8104 8943 49
                    Compuserve: 100272,507
                    Email: sales@lauterbach.com
                    WWW: http://www.lauterbach.com
      USA           Lauterbach Inc.
                    945 Concord Street, Framingham,MA 01701
                    (508)620-4521   Fax: (508)620-4522

    Lear Com Company
                    2440 Kipling St. Suite 206, Lakewood, CO  80215
                    (303)232-2226   Fax: (303)232-8721

    Logical Systems Corporation (Disassembler, Simulator)
    Micro Dialects, Inc.
                    POB 30014, Cincinnati, OH  45230

    Logisoft        Box 61929, Sunnyvale CA  94086
                    (408)773-8465  Fax: (408)773-8466

    L.S. Electronic Systems Design
                    2280 Camilla Rd., Mississauga, Ontario
                    Canada  L5A 2J8
                    (905)277-4893   Fax: (905)277-0047

    Lumino B.V
                    Web: http://www.lumino.nl/lumino/

    Mandeno Granville Electronics, Ltd
                    128 Grange Rd., Auckland 3, New Zealand
                    +64 9 6300 558   Fax: +64 9 6301 720

    Matra Semiconductor
                    2840-100 San Tomas Expressway, Santa Clara, CA  95051

    MDL Labs
                    1073 Limberlost Court,  Columbus, OH 43235
                    Tel/Fax: 614-431-2675
                    Email: arl@infinet.com

    MetaLink Corporation
    North America   325 E. Elliot Road, Chandler, AZ  85255
                    (800)638-2423   (602)926-0797
                    Fax:  (602)926-1198
    Europe          MetaLink Europe GmbH
                    Westring 2, 8011<85614>
                    Kirchseeon-Eglharting, Germany
                    (08091)2046   Fax: (08091)2386

    Micro Computer Control Corporation
                    PO Box 275, 17 Model Ave., Hopewell, NJ  08525
                    (609)466-1751   Fax: (609)466-4116
                    BBS: (609)466-4117
                    Email: 73062.3336@compuserve.com

    Micro Future    40944 Cascado Place, Fremont, CA  94539
                    (510)657-0264   Fax: (510)657-5441
                    BBS: (510)657-5442

    MicroMint       4 Park St., Vernon, CT  06066
                    (203)875-2751   Fax: (203)872-2204

    Microtek International, Inc.
    North America   Microtek International, Inc.
                    3300 N.W. 211th Terrace, Hillsboro, OR  97124
                    (503)645-7333   Fax: (503)629-8460
    Europe          Microtek Electronics Europe GmbH
                    Starnberger Strasse 22, 82131 Gauting bei Munchen
                    +49(89)893139-30    Fax: +49(89)893139-50

    MPE: MicroProcessor Engineering Ltd.
                    133 Hill Lane, Shirley, Southampton SO1 5AF U.K.
                    +44 1703 631441   Fax: +44 1703 339691
                    Email: mpe@mpeltd.demon.co.uk

    New Micros of Dallas Texas

    Nohau Corporation
                    51 E. Campbell Ave., Campbell, CA  95008
                    (408)378-2912 (24 hr. information center)
                    Fax: (408)378-7869
                    Email: nohau@shell.portal.com
                    WWW: http://www.nohau.com/nohau

    Offete Enterprises, Inc.
                    1306 South B Street, San Mateo, CA  94402
                    (415) 574-8250

    Okapi Systems   (206)258-1163

    Onset Computer Corporation
                    199 Main St.,  P.O. Bos 1030
                    North Falmouth, MA 02556-1030
                    (508)563-9000   Fax: (508)563-9477

    Orion Instruments, Inc.
                    1376 Borregas Avenue, Sunnyvale, CA  94089
                    (408)747-0440  Fax: (408)747-0688
                    Email: info@oritools.com

    Orion Instruments
                    180 Independence Drive, Menlo Park, CA  94025
                    (800)729-7700   Fax: (415)327-9881

    Philips Microcontroller Product Group
                    811 East Arques Ave. / POB 3409
                    Sunnvale, CA  94088-3409
                    Technical documentation:
                        Sunnyvale, CA - (800)447-1500  Fax: (408)991-3773
                        Eindhoven, Netherlands - Fax: 31-40-724825
                    Technical questions:
                        Sunnyvale, CA - (408)991-3518

    Phyton, Inc.    7206 Bay Parkway, 2nd floor
                    Brooklyn, N.Y. 11204, USA
                    Phone: (718)-259-3191
                    Fax: (718)-259-1539
                    e-mail: info@phyton.com

    Production Languages Corporation
                    P.O. Box 109, Weatherford, TX  76086
                    (800)525-6289   (817)599-8365   Fax: (817)599-5098

    Prologic Designs
                    PO Box 19026, Baltimore, MD  21204
                    (410)661-5950   Fax: (410)661-5950

    PseudoCorp      2597 Potter St., Eugene, OR 97405
                    (541)683-9173   Fax: (541)683-9186
                    Email: rhowden@teleport.com
                    Web: http://www.teleport.com/~rhowden

    Quantasm Corporation
                    19672 Stevens Creek Blvd.
                    Cupertino, CA  95014
                    (800)765-8086   (408)244-6826   Fax: (408)244-7268

    Raven Computer Systems
                    PO Box 12116, St. Paul, MN  55112

    Rigel Corporation
                    P.O. Box 90040, Gainesville, FL  32607

    Scientific Engineering Labs
                    255 Beacon St., Suite 3D, Somerville, MA  02143

    Infineon Technologies Inc. (formerly Siemens Microelectronics)
                    Integrated Circuit Division, 10950 N. Tantau Ave.
                    Cupertino, CA  95014
                    (800)777-4363  Fax: (708)296-4805

    Signetics Corporation (see Philips Microcontroller Product Group)

    Signum Systems  Mountain View, CA     (415)903-2220
                    Thousand Oaks, CA     (805)371-4608

    Software Science
                    3570 Roundbottom Rd., Cincinnati, OH  45244
                    (513)561-2060  Fax: (513)271-3181
                    Email: pbarnes@iglou.com

    Sophia Systems  NS Bldg. 2-4-1, Nishishinjuku, Shinuku-ku
                    Tokyo 160, Japan

    Speech Technology Inc., Software Division
                    837 Front Street South, Issaquah, WA  98027

    SPJ Systems     114, Chitrashala Bldg.
                    562, Sadashiv Peth
                    Pune, India 411 030
                    +91-20-4451607   Fax: +91-20-4480285
                    Email: spj@spjsystems.com
                    Web: http://www.spjsystems.com

    Standard Microsystems Corporation
                    80 Arkay Dr.,  Hauppage, NY  11788
                    (516)435-6000    Fax: (516)231-6004
                    WWW: http://www.smc.com
                    Email: techsupport@smc.com

    StarCom         WWW: http://www.n2.net/starcom

    Sun Equipment Corporation
    Lodestar Electronics Corp.
                    616 Hawick Rd., Raleigh, NC  27615
                    (800)870-1955   (919)881-2141   Fax: (919)870-5720

    Suncoast Technologies
                    P.O. Box 5835, Spring Hill FL 34606
                    Voice/FAX (352)596-7599
                    Email: suncoast@earthlink.net
                    WWW: http://home.earthlink.net/~suncoast/

    Sysoft SA       (closed as of 1989 - see KC Automation GmbH)

    Systronix Inc.  555 S. 300 E., Salt Lake City, UT  84111
                    (801)534-1017  Fax: (801)534-1019
                    BBS: (801)487-2778

                    11 Ally22 Ln21 Pei-Ta Rd.
                    Hsin-Chu City, Taiwan, R.O.C.
                    (886)3-532-7372   Fax: 886-3-531-7162

    URDA, Inc.      (800)338-0517   (412)683-8732

    US Software     14215 N.W. Science Park Drive, Portland, OR  97229
                    (800)356-7097   (503)641-8446   Fax: (503)644-2413
                    Product information available by ftp -
                       ftp.netcom.com : pub/ussw

    Universal Cross Assemblers
                    (506)849-8952   Fax: (506)847-0681

    Vail Silicon Tools, Inc.
                    Box 165, Pompano Beach FL  33069
                    (305)491-7443   Fax: (305)974-8531

                    1511 Buckeye Dr., Milpitas, CA
                    (408)432-8888   Fax: (408)432-0640
                    Email: info@smtpgat.xicor.com
                    BBS: (800)258-8864

    Zax Corporation
                    2572 White Road, Irving, CA 92714
                    (800)421-0982   (714)474-1170

    Zitek Corporation
                    1651 East Edinger Ave., Santa Ana, Ca  92705

back to top


5.1) Periodicals that cover the 8051

    Various magazines and journals (journals seems to be THE popular name
    for magazines these days) provide articles from time to time on the
    8051 family of microcontrollers:

    The Computer Applications Journal (Circuit Cellar Ink)
        - programming and construction articles
        - POB 7694, Riverton, NJ  08077-8784
        - FAX: (203)872-2204
        - Voice orders: (609)786-0409
        - Email orders: ken.davidson@circellar.com
        - BBS: (203)871-1988
          WWW: http://www.circellar.com
        - $21.95, $31.95 surface Canada and Mexico,
          $49.95 air all other countries

    Computer Design
        - industry announcements and trends
        - One Technology Park Drive, P.O. Box 990, Westford, MA  01886
        - (508)692-0700

    The Computer Journal
        - programming and construction articles, specializing in 8-bit
          and older computers (Z80-CP/M, TRS-80, Xerox, microcontrollers,
        - programming and construction articles, specializing in old
          computers (S-100, CP/M, TRS-80, Xerox, Adam, etc)
        - P.O. Box 3900, Citrus Heights, CA 95611-3900
        - (800)424-8825 or (916) 722-4970   FAX: (916) 722-7480
        - BBS: (916) 722-5799
        - Web: http://www.psyber.com/~tcj
        - Email: tcj@psyber.com
                 Dave Baldwin: dibald@netcom.com
                 Bill Kibler: kibler@psyber.com
        - USENET newsgroup alt.tcj

    Dr. Dobbs Journal
        - programming articles, concepts, and designs
        - 411 Borel Ave., San Mateo, CA  94402
        - (415)358-9500

        - Cahners Publishing Company
          8773 South Ridgeline Blvd., Highlands Ranch, CO 80126-2329
        - annual microprocessor and DSP editions
        - http://www.ednmag.com/

    Electronic Engineering Times
        - industry announcements and trends
        - FREE to qualified engineers and managers involved in
          engineering decisions
        - Fulfillment Dept., PO Box 9055, Jericho, NY  11753-8955
        - FAX: (516)733-6960

    Electronics Now
        - construction articles
        - Box 55115, Boulder, CO  80321-5115
        - $19.97 one year

    Elektor Electronics
        - programming and construction articles
        - World Wide Subscription Service Ltd
          Unit 4, Gibbs Reed Farm, Pashley Road
          Ticehurst TN5 7HE, England
        - 27 UK pounds
        - Old Colony Sound Lab, P.O. Box 243, Peterborough, NH 03458
        - Tel. (603)924-6371, 924-6526
        - Fax: (603)924-9467
        - $57 USA and Canada per year

    Embedded Systems Programming
        - programming and systems design articles
        - Miller Freeman Publications
        - 500 Howard St., San Francisco, CA  94105
        - Miller Freeman: (415)905-2200
        - Embedded Systems Programming phone: (800)829-5537

    Forth Dimensions
        - monthly magazine on Forth
        - Forth Interest Group, P.O. Box 2154, Oakland, California 94621
        - (510)893-6784   Fax: (510)535-1295
        - Email: johnhall@aol.com
        - Forth Interest Group home page:

    Inquisitor Magazine
        - If you're the type that watched Gilligan's Island for its
          socio-political insights, then you'll love a new 'zine that
          just crossed my desk - Inquisitor Magazine.  It's general
          philosophy seems to be ... well, it seems to be ... uh, yeah!
          Technical in nature, bizarre, tongue in cheek, eclectic,
          electric, did I mention bizarre(?), and lots of fun.  Worth
          looking at if you like the out of the ordinary.  The moving
          force behind this magazine is Daniel Drennan, who seems to have
          suffered from an overdose of radiation from his computer
          monitor ;-).
        - Planetarium Station, P.O.Box 132, New York, NY  10024-0132
        - (212)595-8370
        - Email: inquisitor@echonyc.com
        - $16 per year (4 issues)

    Microcomputer Journal
        - programming and construction articles
        - Midnight Engineering, 1700 Washington Av., Rocky Ford, CO 81067
        - (719)254-4558  Fax: (719)254-4517

    Midnight Engineering
        - 1700 Washington Ave., Rocky Road, CO  81067
          (719)254-4558   Fax: (719)254-4517

    MW Media - Product Directories
        - 8051 Product Directory
          (survey of various 8051 products)
        - Intel Development Tools Handbook
          (survey of commercial development tools for the 8051, 8096,
          and 80186 lines of Intel microprocessors)
        - This documents could very well be a "must" if you're into
          serious development using one of these chips.  If you are
          "just" a hobbyist, see how the "other half" lives.
        - other guides on Intel development tools, Embedded Intel 386,
          Intel 486/Pentium, 8051 products, Hitachi microcontroller
          development tools, AMD FusionE86, AMD 29K; low power products,
          DSP, multimedia CD
        - FREE to qualified developers
        - MW Media
        - Fairmont Plaza, 50 W. San Fernando, #675, San Jose, CA  95113
        - (408)288-4721 and (408)286-4200
        - FAX: (408)288-4728

    Nuts & Volts Magazine
        - A National Publication for the Buying and Selling of
          Electronic Equipment
        - 430 Princeland Court, Corona, CA  91719
        - Mailed third class, USA only:  $17.00 one year
                                         $31.00 two years
        - Mailed first class, one year only:  $34.00-USA
        - Foreign/Air Mail - $70.00;  Foreign/Surface - $39.00
        - (800)783-4624
        - Email:  74262.3664@compuserve.com

5.2)  Books on the 8051

5.2.1)  List of books

    I don't have information on all of these, only that they exist.  I
    would greatly appreciate it if someone could provide a short synopsis
    and the complete book name if you are familiar with any of these

    The 8051 Family of Microcontrollers
        - Richard H. Barnett
        - Prentice-Hall, 1995
        - ISBN 0-02-306281-9

    8051 Interfacing and Applications
        - Applied Logic Engineering
        - 13008 93rd Place North, Maple Grove, MN  55369
        - (612)494-3704

    The 8051 Microcontroller
        - I. Scott MacKenzie
        - Prentice Hall
        - 2nd edition, 1995
        - ISBN 0-02-373660-7
        - includes schematics for a single-board computer,
          assembly-language source code for a monitor program, and
          interfaces to a keypad, LEDs, and loudspeaker

    The 8051 Microcontroller
        - James W. Stewart
        - Regents/Prentice-Hall, 1993
        - $27.50, 273 pages
        - includes many interfacing examples (switches, solenoids,
          relays, shaft encoders, displays, motors, and A/D converters)
          and a chapter on top-down design method

    The 8051 Microcontroller: Architecture, Programming and Applications
        - Kenneth J. Ayala
        - 241 pages, soft cover
        - 5.25" diskette with assembler and simulator
        - ISBN 0-314-77278-2, Dewey 004.165-dc20
        - West Publishing Company
        - P.O. Box 64526, St. Paul, MN  55164
        - (800)328-9352
        - see review in next section

    Assembly Language Programming (for the MCS-51 family)
        - F. A. Lyn
        - L. S. Electronic Systems Design

    Basic-52 Programmer's Guide
        - Systronix, Inc. (they also sell a Basic compiler)

    Beginner's Guide
        - Suncoast Technologies

    C and the 8051
        - Thomas W. Schultz
        - Prentice Hall
        - ISBN 0-13-753815-4

    Data book / Handbook / Users' Guide
        - Advanced Micro Devices
        - Dallas (User's guide for the DS5000)
        - Intel
        - Philips
        - Infineon Technologies

    Embedded Controller Forth for the 8051 Family
        - Academic Press (I think)
        - William H. Payne
        - uses a Forth development system available on the Internet
          (see above in the Forth software section)

    Embedded Systems Programming in C and Assembler
        - John Forrest Brown
        - Van Nostrand Reinhold, 1994
        - 304 pages, $49.95
        - ISBN 0-442-01817-7
        - covers Motorola and Intel processors
        - includes diskette with code from the book
        - book review in Dr. Dobb's Journal, November 1994, page 121

    Experimenter's guide
        - Rigel Corporation

    Flow Design for Embedded Systems
        - Barry Kauler
        - R&D Books / Miller Freeman (USA), 1997
          distributed in Europe by McGraw-Hill
        - ISBN 0-87930-469-3
        - http://www.rdbooks.com/
        - bundled with a sophisticated graphical diagrammer and CASE
          tool, K-Flow diagrammer, that runs on Windows 3.1 or 95
        - source code for the TERSE RTOS is supplied

    Introduction to Microcontroller Design, Based on the 8051 family of
        - Business Data Computers
        - P.O. Box 1549, Chester, CA  96020

    The Microcontroller Idea Book
        - Jan Axelson (of Microcomputer Journal fame)
        - features the 8052-BASIC microcontroller
        - hands-on guide with complete plans (schematics, design theory,
          program listings, construction details, etc)
        - explains how to use sensors, relays, displays, clock/calendars,
          keypads, wireless links, and more
        - 1994, 273 pages, $31.95 + shipping
        - Lakeview Research, 2209 Winnebago St., Madison, WI  53704
        - contact the author at jaxelson@lvr.com
        - WWW: http://www.lvr.com/
        - Lakeview Research's microcontroller page (resources for
          8052-Basic projects): http://www.lvr.com/microc.htm

    Programming and Interfacing the 8051 Microcontroller
        - Sencer Yeralan and Ashutosh Ahluwalia
        - wealth of information, including: 8051 architecture,
          programming basics and techniques, on-chip features, building
          your own 8051 system, and interfacing to various peripherals
        - hardware experiments contains plans and code for:  scanning a
          keypad, stepper motor control, a frequency generator, measuring
          light and temperature intensity (analog to digital), digital to
          analog conversion, DC motor speed regulation, interfacing to
          intelligent Liquid Crystal Displays, and implementing a
          multi-drop RS-485 network
        - accompanying diskette has an 8051 simulator and all source code
          for the projects in the book
        - must have book for the hobbyist or professional
        - $34.38, 352 pages, paperback, ISBN 0-201-63365-5
        - Addison-Wesley

5.2.2)  Book reviews

    Russ Hersch's review of the book:
    Programming and Interfacing the 8051 Microcontroller
    by Sencer Yeralan and Ashutosh Ahluwalia

       Addison-Wesley has just released a GREAT new book, "Programming
       and Interfacing the 8051 Microcontroller" by Sencer Yeralan and
       Ashutosh Ahluwalia.  I had actually reviewed the manuscript some
       time back, and the book has now finally been released.  This book
       contains a wealth of information - it answers a lot of Frequently
       Asked Questions that often appear in comp.robotics,
       sci.electronics, and comp.arch.embedded.

       Among the some of the basic subjects covered include: 8051
       architecture, programming basics and techniques, on-chip features,
       building your own 8051 system, and interfacing to various
       peripherals.  A section on hardware experiments contains plans and
       code for:  scanning a keypad, stepper motor control, a frequency
       generator, measuring light and temperature intensity (analog to
       digital), digital to analog conversion, DC motor speed regulation,
       interfacing to intelligent Liquid Crystal Displays, and
       implementing a multi-drop RS-485 network.

       The book comes with a diskette containing an 8051 simulator and
       all source code for the projects in the book.  This is a must have
       book for the hobbyist or professional.  Available for $34.38, 352
       pages, paperback, ISBN 0-201-63365-5.  Run, don't walk, to your
       bookstore and get one now.  I mean it, this is a great book.

    Russ Hersch's review of the book:
    The Microcontroller Idea Book
    by Jan Axelson

       This book is loosely based on a series of articles Jan wrote for
       ComputerCraft magazine (now the Microcomputer Journal).  If you
       are at all familiar with her work, you already realize that you're
       wasting your time by reading this review and you might as well
       just order your copy now.

       This is an excellent book for hobbyists and tinkerers, as it
       includes complete circuit schematics and parts lists, design
       theory, example program listings, construction and debugging tips,
       and vendor listings.  The example circuits and programs are based
       on the 8052-BASIC chip (a favorite with hobbyists due to its ease
       of use), and there is a lot of material on programming in BASIC52.
       The book is [very] useful even if you use a standard 8051 part.
       Lots of different interfacing ideas including: sensors, motors,
       LEDs, LCDs, wireless links, and a LOT more.

       Chapter titles:  microcontroller basics, inside the 8052-
       BASIC, powering up, saving programs, programming, inputs and
       outputs, switches and keypads, displays, using sensors to
       detect and measure, clocks and calendars, control circuits,
       wireless links, calling assembly-language routines, running
       BASIC-52 from external memory, related products

       If you are just starting out with microcontrollers, and don't have
       a clue where to start or what to control, this book is just what
       you need.  As the title of the book says, it's an idea book.

            The Microcontroller Idea Book
            Jan Axelson
            1994, 273 pages, $31.95 + shipping
            Lakeview Research, 2209 Winnebago St., Madison, WI  53704
               Email: jaxelson@lvr.com
               Web: http://www.lvr.com/

    Russ Hersch's review of the book:
    The 8051 Family of Microcontrollers
    by Richard H. Barnett

       This book VERY thoroughly discusses the design and implementation
       of controllers using the 8051.  Dick says his book is "lots of
       meat, very little filler", but he's a bit off the mark here.  What
       he means to say is this book is many large chunks of meat, no
       vegetables, and no potatoes - we are NOT talking Hamburger Helper
       here gang.  The introduction alone contains circuits for 3
       controllers (one 8085 design used as a comparison).  Many hardware
       and softare examples are included.  Everywhere you turn in this
       book, you'll find circuit diagrams and sample code, including
       complete designs for three different microcontroller projects in
       the last chapter.  Clear and in-depth coverage of interfacing and
       peripheral use leaves very little to the imagination.

       This is a good book for both students and professionals who are
       trying to figure out how to start designing there own
       microcontroller.  Experienced hobbyists will also appreciate the
       many examples.  Novices might be a bit overwhelmed by this book.

            The 8051 Family of Microcontrollers
            Richard H. Barnett
            Prentice-Hall, 1995
            ISBN 0-02-306281-9

       For more info contact the author - rbarnett@purdue.edu

    Richard Kendrick's review of the book:
    8051 Interfacing and Applications
    from Applied Logic Engineering

       IN BRIEF

       An excellent collection of interfacing circuits and well commented
       source code in assembly.  This is not a book for beginners as it
       assumes the user is very familiar with the architecture of the
       8051 and its registers.  A disk of assembly source code listings
       is included.


             1    - 8051 Interfacing and Applications
             1.1  - Introduction
             1.2  - Main System Core
             1.3  - Simple Methods of User Input
             1.4  - Interfacing a 16 digit keypad to the 8031
             1.5  - Centronics Parallel Input Port
             1.6  - Centronics Parallel Output Port
             1.7  - Interfacing to the built-in Serial Port
             1.8  - Interfacing to a Dual Channel UART
             1.9  - Interfacing to an LCD
             1.10 - Bank Selection of Memory
                  - Appendix A: List of Vendors
                  - Appendix B: Connection to an External Computer
                     0.1 RS-232 Serial Connection
                     0.2 Centronics Interface Cabling


       This spiral bound book is thin (74 pages) but manages to cover a
       lot of information.  All of the sub-chapters have excellent code
       listings with full comments, partial schematic diagrams, and an
       occasional timing diagram.  The chapter on using the serial port
       is based on the MAX232 chip becoming so popular.  A table of timer
       reload values is provided to get standard baud rates but the book
       only mentions the required clock frequency of 11.0592 mHz in the
       first chapter.  It also doesn't explain why a seemingly
       non-standard crystal frequency was chosen.  The dual UART channel
       features the 2681 chip.  The LCD chapter gives a small but
       adequate explaination of the Hitachi controller chip usage on LCD
       displays and a tiny fragment of data on display characteristics of
       LCDs.  The bank selection of memory is useful showing code and
       schematic using five 62256 chips for 160K bytes of read/write

    Richard Kendrick's review of the book:
    Microprocessor/Controller Design
    by Wayne P. Lichti of Business Data Computers

       A lame little book better bypassed.  As an introductory text,
       Kenneth Ayala's book is the winner hands down.  This book is a
       poor rehash of the same information in Intel's or AMD's data book.
       There is one code listing in the book and does little more than
       tell the reader that the 8051 family of processors exist.

       This book is 134 pages of wasted time.  The schematics were
       printed on a dot matrix printer and poorly reproduced.  Many of
       the sections are just a table or a paragraph with two or three
       sentences.  Use Ayala's book, you'll learn a lot more useful

    John Little's review of the book:
    The 8051 Microcontroller: Architecture, Programming and Applications
    by Kenneth J. Ayala

       IN BRIEF

       A good book for those who are already moderately familiar with
       assembly language programming and wish to learn more about 8051
       specifics.  Has many example listings, all of which are very well
       documented in terms of comments and explanations in the text. NOT
       a book for absolute beginners OR hardware hackers looking for
       circuits and applications.


          1 - Microprocessors and Microcontrollers.
          2 - The 8051 Architecture.
          3 - Moving Data.
          4 - Logical Operations.
          5 - Arithmetic Operations.
          6 - Jump and Call Opcodes.
          7 - An 8051 Microcontroller Design.
          8 - Applications.
          9 - Serial Data Communication.
          A - 8051 Operational Code Mnemonics.
          B - How to Use the Assembler.
          C - how to Use the Simulator.
          D - The 8255 Programmable I/O Port.
          E - Control Registers.


       In his preface to the book, Mr Ayala states that that it is
       intended for "... a diverse audience. It is meant for use
       primarily by those who work in the area of electronic design and
       assembly language programming of small, dedicated computers".
       Later, he goes on to refer the reader to the manufacturer's data
       books for more information on hardware issues. This sets the tone
       for the whole book, which is very much software orientated.

       Anyone buying the book expecting to find reams of circuit diagrams
       and details on how to build their own 8051 driven, automated car
       assembly plant will be disappointed. In fact, most of the circuits
       and applications shown are very much conceptual, with generic,
       black-box outlines for most of the components. The single
       exception to this is a fairly complete system (8031, EPROM & RAM,
       jumper selectable memory sizes) in the chapter on microcontroller
       design.  Even then, there's no I/O shown (the txd/rxd are

       Having said that, Mr Ayala does do a fairly thorough job of
       working through the peculiarities of the 8051, with detailed
       coverage of memory organisation, bit/byte level operations,
       timers, interrupts and, at the end of the book, a complete chapter
       on 8051 communication modes. Each area has relevant assembly
       language listings, along with a detailed explanation of the
       workings of the code.

       Each section also has highlighted "comment" passages which point
       out common pitfalls and reinforce critical points. Each chapter
       ends with a summary of the important points covered and a series
       of ten to twenty pertinent problems for the reader to solve. For
       the most part, the answers to the problems can be found in the
       text.  In later chapters though, the reader is asked to elaborate
       on various programming themes and to write assembly language
       programs of their own to perform various tasks. The problems range
       from the bland "Name twenty items which have a built in
       microcontroller" (Chapter 1), to the more esoteric "Compose a
       40-value lookup table that will generate a sawtooth wave using a
       D/A converter" (Chapter 8).

       It should be noted that the book is not aimed at the complete
       novice. For instance, although assembly language listings are used
       throughout, it is not until Appendix B that the reader finds out
       what the assembler actually does and how the listings relate to
       machine code. Even then, the complete neophyte will be left with a
       rather empty feeling, as there are pages and pages of code, the
       schematic for a (more or less) complete system and instructions on
       how to use the assembler, but no information at all on how the
       object code should be utilised (other than with the included
       simulator - see below). If you don't already know how to blow an
       EPROM, you're in trouble.

       The diskette which accompanies the book contains the PseudoSam
       assembler (which is used throughout) and an 8051 simulator. Both
       being intended for use on a PC (it's a measure of how fast the
       computer industry is evolving that a 5.25 inch diskette seems a
       little archaic just three years after the publication date of the
       book).  The PseudoSam assembler ran fine on my system and I was
       able to assemble several of the examples from the book and
       successfully run them on a small, home-brew 8031 system. I was
       totally unable to get the simulator to run. However, as it failed
       on several different systems I'm prepared to believe that my
       particular copy of the diskette was at fault.


       All in all, a recommended book for those who have previous
       assembly language experience and wish to get to know details
       relating to the 8051 microcontroller. While the internal
       architecture of the chip is covered in detail, external hardware
       and peripheral interfacing is not.  Only the basic 8051/31 is
       covered, with little mention of the other variants available.
       There are extensive listings in the text, covering routines for
       handling keyboards and displays, as well as timing loops and
       communications. A large, clear typeface ensures that all of the
       listings are completely legible. The layout and presentation of
       the book is excellent, with a consistent, unambiguous style used

    Tim McDonough's review of the book:
    C and the 8051: Programming for Multitasking
    by Thomas W. Schultz

       Schultz's book provides a brief overview of the 8051 architecture
       but is primarily a discussion of multi-tasking software in an 8051
       environment.  He presents quite a few code examples.  The examples
       and the accompanying text show comparisons of how to accomplish
       things in assembler, PLM, and C.  The C examples presented are
       based on Version 3 of the Franklin compiler but should be easily
       understandable by anyone already familiar with C.

       Later chapters in the book deal with more advanced topics.
       Chapters are devoted to Real-Time Ideas, Timing and Scheduling,
       Communications and Synchronization, Interrupts, Priority, and
       Context, and Distributed Systems.  The Real-Time Ideas chapter
       briefly discusses six Real Time Operating System (RTOS) kernels
       offered by several vendors.  Later in the book some examples are
       given to simple applications with and without using a RTOS.

       All in all, a useful addition to my technical library.  It is one
       of the few 8051 books that goes beyond the basics and would be
       particularly of interest to those contemplating their first
       non-trivial 8051 design.

    Russ Hersch's review of the book:
    Basic-52 Programming
    by Bruce Boyes, Will Bagley, and Scott Kendall of Systronix, Inc.

       A must have book for Basic-52 programmers.  The book starts out
       with an introduction to BASIC-52 programming, program editing, and
       techniques.  About a hundred of the book's 160 pages are a
       detailed and quite useful reference of the commands and
       statements.  Six appendixes covering advanced topics round out
       this most useful volume.  A quick index to commands, operators,
       and instructions printed on the back cover of the book is a nice
       finishing touch.  For only $20.00, it's a bargain at twice the
       price.  Well, let's not get carried away, but if you're
       programming in Basic-52, this book is indispensible.

5.3)  Miscellaneous documentation on the 8051

    Advanced Micro Devices
        - application notes

    Intel Corporation
        - application notes

    L.S. Electronic Systems Design
        - application notes (source code on diskette and schematics)

    Philips Semiconductors (Signetics)
        - application notes

    Software Science
        - application notes


I disclaim everything.  The contents of this article might be totally
inaccurate, inappropriate, misguided, or otherwise perverse - except for
my name (hopefully I got that right).

Copyright  2000 CPU Technologies and Microcontroller.com, all rights reserved
Original Copyright  1997 by Russ Hersch.
This FAQ may be posted to any USENET newsgroup, on-line service, or BBS
  as long as it is posted in its entirety and includes this copyright
This FAQ may not be distributed for financial gain.
This FAQ may not be included in commercial collections or compilations
   without express permission from the author.



Cores   |  Tools  |  App Notes  |  References  |  Semiconductors  |  Tutorials  |  What's Inside
Editorials  |  News  |  Marketplace  |  Events  |  Jokes  |  Contact  |  CPU Technologies  |  Privacy Statement

Waddya think of Microcontroller.com? Email us your comments!

* * * Legal Gibberish * * *
Copyright 2000 CPU Technologies. All Rights Reserved. Information provided "as-is" without warranty. Please see details.
Contact Microcontroller.com for usage and copy permission.