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tehKaiN / ROMprg

Universal ROM/flash programmer project based around Arduino Mega-compatible boards
GNU General Public License v3.0
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Add GPIO to toggle /TIME signal on megadrive shield #1

Open tehKaiN opened 5 years ago

tehKaiN commented 5 years ago

/TIME is NOT clock. It's pin B31, and is low when the CPU accesses 0xA13000 through 0xA130FF.

It's used to toggle SRAM and other stuff in megadrive carts. This way it'll be possible to dump multicarts and SRAM saves.

Some info about banking:

http://forums.nesdev.com/viewtopic.php?t=11615 http://devster.monkeeh.com/sega/radica/

tehKaiN commented 5 years ago

this could be done using 74 chips on address lines, but the less components the better. And there's still plenty of GPIOs for use.