Help! MMC5 dev cart issue

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Help! MMC5 dev cart issue

Post by mightydidz » Wed Feb 03, 2021 11:47 am

I build myself a MMC5 dev cart to test romhacks and transalation.
I really simple schematic using a 62256 sram and 2x27c801 eeprom.
Jumpers for SL/CL mode but its currently in CL mode.

It not working correctly, I'm having garbled sprites, sometime it freezes, sometime I have to press reset couple of times to have it boot correctly.
Its a plain 72pin cartridge, no adapter. ciram-a10 and ciram-/cs are connected directly to mmc5

I've reflowed the mmc5 couple of times to make sure welds are strongs
Only one side is a bit off, but I'm confided the connections are good.
Here's a picture of the welds and my schematic

Here is a video I made with couples of games showing the problems

If anyone have any hints on what's going on that would help me alot.
mmc5 test.pdf
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