sanni / cartreader

A shield for the Arduino Mega that can back up video game cartridges.
GNU General Public License v3.0
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GBM: Fix some comments and unused function #1020

Closed msinger closed 3 months ago

msinger commented 3 months ago

These are just some changes in comments and in one unused function. It has no effect, but I would like to submit this for documentation purposes.

I played around with the NP GB Memory cartridge on a different hardware and your code helped me to be able to fully read and write the cartridge. But I figured out by testing that some of the comments are not correct. Especially the GBM command 0x05 does NOT map the menu. It re-enables the mapping that was selected previously. So, if the menu was selected before disabling the mapping with the 0x04 command, then the menu mapping will be re-enabled again when sending the 0x05 command. But if some other mapping was selected before (like with 0xC1, 0xC2, ...), then that particular mapping will be re-enabled by 0x05.

I don't know if this behavior also applies to the NP SNES cartridges. I don't have the hardware to test it.

Did you reverse engineer those commands by yourselves? Or did you find some documentation online somewhere? I would be happy if you remember the URL in that case.