Hi,

Do you think this will work for in-circuit programming of an EEPROM while in an 8085 cpu circuit. I got it from ChatGPT:

8085 Pinout:


Example Workflow:

1. Assert HOLD: The Arduino sets the HOLD line high.
2. Wait for HLDA: The Arduino waits until the 8085 asserts HLDA.
3. Program EPROM: The Arduino drives the address, data, and control lines to program the EPROM.
4. De-assert HOLD: The Arduino sets the HOLD line low.
5. 8085 Resumes Operation: The 8085 de-asserts HLDA and continues normal operation.

Thanks, Kei

 

Try asking ChatGPT if it will work.

 

Haha, I don't need any "checkup". Better try asking myself instead, I think it will work, but it is more trouble than it is worth because it would also require bidirectional SPDT electronic switches to connect the EEPROM address and data lines between the cpu and arduino, as well as rd,wrt and chip select pin(which could be grounded when not connected to the 8085)...Better to do it through software using a hex loader stored on the EEPROM which could store bytes on the EERPROM below the monitor code or a separate RAM chip. I am just trying to avoid yanking out the EEPROM out of its zif socket every time to re-program it.

- Kei

 

Can't you use the tristate capability of both the 8085 and the arduino instead of extra SPDT switches?
Something like: https://github.com/bazsimarkus/Simple-8085-Arduino-System

 

Thanks Michael, that is a good idea, I will review it.

-Kei