WRAM: ZMD U6264BDC07LL
CHR RAM: Alliance Megabit U6264BDC07LLG1
Numbers are close, so there may not be a difference, but it's worth a shot anyway.
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WRAM: ZMD U6264BDC07LL
Pin 2 on the AX5202 connects to the MMC1/3 solder pad, as does RAM pin 20, so there's a match. Pin 12 of the AX5202 appears to go to the bottom of the 27k resistor (R3). Pin 38 goes to the PRG, and pin 40 connects to a .1uf capacitor. Pin 26 of the RAM goes through the 10k resistor at R2, through the VRC/Battery pad on the battery side, and then through pins 1 and 28, and the 22uf cap at C4. It's actually hard to see the traces because the boards are completely black, so I may have made an error here, but I triple checked the paths and I'm pretty sure of them.lidnariq wrote: ↑Wed Apr 28, 2021 5:20 pm Those "LL"s at the end should indicate that it's a RAM that knows how to stop drinking. So I expect something else isn't correctly telling it when.
Theoretically, pins 12 and 2 or 38 and 40 depending on specific AX5202 should ultimately connect to RAM pins 20 and 26, so I guess I'd make sure that electrical path looks clean.
Ok, great, you're dealing with variant "#1".
That ... doesn't sound right. Pin 12 of the AX5202 ought to connect to pin 26 of the RAM and also some side of some resistor.Pin 12 of the AX5202 appears to go to the bottom of the 27k resistor (R3). Pin 26 of the RAM goes through the 10k resistor at R2, through the VCC/Battery pad on the battery side
Could be a bad design, I have no idea, and the black silkscreen makes it harder to figure out.Or possibly a defective board, although everything works fine other than saving
Please note that is only for some games that have a hard time with newer SRAMs (Faster then 120ns). If you are using older SRAM or your game doesn’t have an issue then it is not needed.and you're using 70ns RAMs (that '07')
I have a bunch of 10k resistors and a single 1k. I'll try the 10k first, and see if that helps. Just gotta wait for the soldering iron to heat up