This one came to me for repair from a buddy who had bravely (foolishly?) bought it off Aliexpress
It's now actually not much cheaper to buy these off Ali than it is to find a reputable seller off eBay. But could be some fun and learning to be had fixing it, so I said I'd take a look.
It had some battery damage that looks like it has been repaired, as well as that weird thing Aliexpress sellers do where they remove the NEO-BUF chip off the slot board and replace it with a bypass... thing.
It actually boots OK and will display test patterns and play sound (bulgy caps and all) so that was a surprise
And it even boots games to the splash screen
When the game code starts is where things start to go wrong.
Text and overlay seems to be OK, Sounds and music are OK (despite those bulging caps)
No sprites, no backgrounds. On some games it will draw the outlines of sprites (spinmasters) or the shadows of backgrounds (metalslug) or weirdly the bottom few lines (puzzle bobble)
So this one is a bit weird, its not complaining about video ram, or palette ram on boot, just doesn't display any video or palette data...
I don't think there was any malice on the part of the Aliexpress seller, the repairs they carried out look reasonably tidy, and I guess their pile of ewaste for repair and quick sale to westerners is huge. As soon as the game boots to splash screen they probably call it good enough and move on to the next one.
Unfortunately I don't have an easy way to get the diag bios onto this one, so I'm thinking I'll unwind and check the repairs that were already done, give the customs the push hard test, then start probing the nearby area for continuity.
Anyone seen something like this before? I've seen lots of watchdog, and lots of glitchy sprites/backgrounds, but never just plain... missing
It's now actually not much cheaper to buy these off Ali than it is to find a reputable seller off eBay. But could be some fun and learning to be had fixing it, so I said I'd take a look.
It had some battery damage that looks like it has been repaired, as well as that weird thing Aliexpress sellers do where they remove the NEO-BUF chip off the slot board and replace it with a bypass... thing.
It actually boots OK and will display test patterns and play sound (bulgy caps and all) so that was a surprise
And it even boots games to the splash screen
When the game code starts is where things start to go wrong.
Text and overlay seems to be OK, Sounds and music are OK (despite those bulging caps)
No sprites, no backgrounds. On some games it will draw the outlines of sprites (spinmasters) or the shadows of backgrounds (metalslug) or weirdly the bottom few lines (puzzle bobble)
So this one is a bit weird, its not complaining about video ram, or palette ram on boot, just doesn't display any video or palette data...
I don't think there was any malice on the part of the Aliexpress seller, the repairs they carried out look reasonably tidy, and I guess their pile of ewaste for repair and quick sale to westerners is huge. As soon as the game boots to splash screen they probably call it good enough and move on to the next one.
Unfortunately I don't have an easy way to get the diag bios onto this one, so I'm thinking I'll unwind and check the repairs that were already done, give the customs the push hard test, then start probing the nearby area for continuity.
Anyone seen something like this before? I've seen lots of watchdog, and lots of glitchy sprites/backgrounds, but never just plain... missing
