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You are here: 8051 Tools Development Board Old Versions Rev 1 (1992) Introduction

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8051 Board, $79
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Rev 4
New Rev 4 Board
A newer version (Rev 4) of this circuit board is available. Rev 4 includes a faster CPU, more memory, more I/O and an optional LCD. We recommend you use Rev 4 for new projects. We are keeping these very old pages on-line for reference to assist people who build the original version of the 8051 development board.
The very old design is difficult to troubleshoot due to the use of an external 27C64 EPROM for the monitor program. We highly recommend you use the new design for any new projects.


To use the 8051 microcontroller, you need to have some sort of a development system. A popular low-cost approach is to buy or build a board containing an 8051 microcontroller, ROM, RAM, a serial port interface, and perhaps some additional I/O capabilities. You install a monitor program such as PAULMON in the ROM, so it will boot the system and allow you to download your code from a PC into the RAM (using an ordinary terminal emulation program), and then you try your code and see if it works. If it dies or otherwise doesn't work, you reboot the 8051 system (pull reset high with a switch), edit and reassemble your code, using an assembler like AS31, and try again. Once it finally works, you can build a dedicated board without the extras and place your code into the ROM.

The assumption here is that you have some time and want to save money by building your own board. Maybe you think it will be fun and interesting, or perhaps you're required to do this for a class? Fortunately, the 8051 is a relatively simple chip, so only a small handful of chips are required. The entire board can be constructed using wire-wrap construction in about two days, plus the time it takes to acquire all the necessary materials.

Go on to the list of what you will need.

Paul's Sample 8051 Development Board Design
Last updated: February 24, 2005
Statue: about 80% done now... need some photos... and proofreading
Suggestions, comments, criticisms, things you want?? <>