Additional information on the JTAG lockout for the EPM7064 and ATF1504. https://www.edaboard.com/threads/quartus-jtag-id-error-using.... It seems that the Altera master programmer can erase/reset the chips and make JTAG work again. It programs the chips not using the JTAG interface.
I found a few Altera master programmers on sale in e-bay. Too expensive! Better is to throw away all EPM7064s, buy new ATF1504s and use a combination of Atmel tools and openocd. I already have two boards with the ATF1504 built here. Will play with them soon...
@S0urceror, can you provide more info on how you use the OpenMSX to interface with the CH376S? I would like to debug your code but it is a nightmare having to program the flash memory every time to test on the MSX computer. I see you pushed the CH376s support to the master branch of your OpenMSX fork but there is no documentation on the requirements or the hardware setup.
I did it as well. I have more experience with those and I believe they are more reliable than the Altera old EPMs. I can also tell you that the trick with 12V always work with the ATF1504s. I bought a batch from China, they came all JTAG locked and I was able to get them all working with the 12V trick. I did the same with a batch of EPMs, only one out of 10 worked ok.
I have just uploaded a new type of driver that I call MSXUSBNext. This Nextor driver is developed in C and can cross-compile to MacOS or Linux. This facilitates fast debugging. The things that need to go fast are of course coded in assembly in a hardware-abstraction-layer.
When you now boot the MSX you are presented with the following boot-menu:
