Yes, I do write a windows software in VB is called "FlashStudioLite" for user to input instruction list i.e. logic code, but my software is not a complier instead it just convert to some predefined code which can be downloaded into AT89S8252 EEPROM area.
BTW, There is so called S.O.S(Supervisory Operating System) in Flash memory area. The S.O.S will fetch user code and execute it until END instruction encounter. Just like standard PLC! Anytime wrong?

My S.O.S is able to scan 660 steps within max.80ms which is good enough for sequence control i.e. Cyclinder type Pick & Place machine or Conveyor operation. I do put AT89S8252 into some small scale machine control and until now it never fail me.


Simon Tew