MiSTer FPGA Forum

Hi,

I need to dump to the SD card the contents of a small EEPROM used in a core. Could you point me to information about how to interface with the firmware to save and read to a file? The core is an arcade so the name of the file could just be derived from the MRA, I suppose.

Thank you
jotego

Can you post details of the actual EEPROM - A chip or whatever it is that has the data you need, picture & part number, I'm a little unclear on exactly what you're trying to accomplish.

I suppose he wants to emulate an EEPROM in an arcade core and has to save it in a file on exit and reload it on starting the core so it does not really matter what the real EEPROM is.

Certain arcade platforms saved/recalled their 'DIP switch' settings to/from an EEPROM.

It is an EEPROM found in arcade games, sized 128 or 256 bytes. I have it already talking with the core and modeled in a BRAM block.

I just need a way to get a serial stream of bits in from the SD card, when the core loads. And then get a stream out on the core request. The name of the file can just be linked to the game name in the MRA file.

There must already exist such an interface in MiSTer. I just need to know the details of it.

Would the computer cores not already do this with floppy disks?

What about the console cores like SNES and Genesis? Wouldn't they be doing the same thing you need for games with SRAM?

MottZilla wrote: ↑Thu Dec 10, 2020 7:37 am What about the console cores like SNES and Genesis? Wouldn't they be doing the same thing you need for games with SRAM?

Minus the "save when the core wants" but yeah pretty much exactly the same thing I'd have thought.

Here is an example of the Genesis core saving and loading Backup ram https://github.com/MiSTer-devel/Genesis ... #L897-L965

https://github.com/MiSTer-devel/Genesis ... #L481-L485