PROG8252

Atmel AT89S8252 in-system programming via PC printer port

WINDOWS VERSION OF A SOFTWARE DOWNLOADER

Some time ago I was forced (partly by curiosity) to find out how to use serial download of AT89S8252.

If you do not know about AT89S8252, believe that it's a really cool 8051 clone equipped with 8 kB of program EEPROM and extra 2 kB of data EEPROM. For more info and .PDF data sheet check Atmel's page.

I wrote a simple DOS program (in Borland Turbo Pascal) which is for serial download/upload of the contents of both internal Flash EEPROM memories. Its quite simple interface enables you to use all serial programming related functions, I haven't played with the timing really, so it might be necessary to change the timing slightly. May be, in future versions, it will be solved..

Serial download is really easy to use, it's enough to connect a crystal to the processor, four wires from printer port and that's all. This is original recommended schematics from Atmel:

I have changed this wiring little bit, mainly because of some basic insulation of your prototype board and the PC. Also the length of the printer cable is compensated some way. Do not forget to connect crystal and power !

Schematics

For the PROG8252 you can download either source code, or compiled .EXE version. Both files are small (less than 20 k), but if you prefere, you can get them in a single ZIP archive. Remember, that the timing is not perfect and you might be forced to change it (I have tested it on my 386DX40). This program is absolutely for free, if you find it useful, let me know.

NEW !!!

Francois du Plessis from South Africa made a Windows version of the PROG8252. It has improved timing method implemented, so it works well on 486s. I've tested the program even on AMD K6/200 MHz. So, if you prefere windows interface or just need better timing, do not hesitate and download it.
Program is again for free, source code is not available.

Questions, comments, more info ? Mail me: jakub.jiricek@centrum.cz

Few troubleshooting notes from recent history:

Keep the ISP cable short (25 cm)

Make sure your crystal oscillates on the right frequency (esp. when above 16 MHz}

Check the stability of your power supply - must be stable DC

If you use 3,3 V chip, mail me and ask for special version of the software - prolonged timing of FLASH burn

Works fine on Athlon 1 GHz/Win 98 SE - I use it on this

No NT support is planned at the moment

This will NOT work with 8051, 89c2051, 89c1051 and similar serial port only equipped ICs, it MIGHT work with AT89S53 from Atmel (requires special ISP port found only in AT89S8252).