I'm new to soldering, only about 1 year or so doing basic stuff. Seeing this in real time def helps me learn to be more patient instead of stone handed Neanderthal.

Cheers mate, and thanks for making your video

Damn that sucks

Hell yeah! Congrats on fixing yours, now you need to find some more and fix them. And yes, there will be more SNES repairs coming, no NES ones yet as it seems all of mine just work, how annoying!

.....EXCEPT if you change all parts and it still doesn't work ;-)

Thanks mate

Interesting. I wonder if it's a CPU fault. I'd highly recommend grabbing a burn in cart, you can get them pretty cheap from AliExpress

Both PPUs have a pin labeled "FIELD" and he looked at both with a scope (they are connected electrically, so the field signal was identical as expected). But I have a sneaking suspicion that "field flag" and field pin are 2 different things.

SD2SNES, but yeah same thing before they had to rename it

Something I edited out was checking those HBLANK and VBLANK pins, along with a few others. They showed 15.7khz and 60hz so I didn't bother going into that. My thoughts are the field flag has something to do with showing progressive or interlaced. The SNES can do both and the 240p test suite is an easy way to swap between them. Unfortunately it wouldn't boot the 240p test suite so I couldn't confirm that. You might have noticed the recent games list on the everdrive is in a different order later in the video from me trying to load up a bunch of different stuff off camera. I haven't been able to confirm it but I'm guessing PPU2 is responsible for switching between 240p and 480i and this is supposed to be reported back to the CPU. If PPU2 doesn't do this as expected or fails to report the correct information back to the CPU, then the field flag has failed to be set.

@@TheRetroChannel So that sounds correct. Well, I looked into the PPU's internal registers from the official docs I found on the Internet Archive and found a software-readable field flag. Since the display output is interlaced, there are 2 fields per frame. The field flag indicates which field it's currently doing -- even lines or odd lines. It's possible that the faulty PPU was only repeating the same frame.

PPU2 generates all clocks, syncs, resets, and makes a video signal from the bitplane data. It contains the DAC and palette registers. Encoder effects like transparency are done there. You can see on the schematic that only the data lines from the VRAM go to PPU2, as the control signals from PPU1 tell it what kind of data is on the bus. PPU1 handles object and map generation, VRAM refresh and access by the CPU, and Mode 7 transformation... basically everything that would affect how graphics data comes out VRAM. The CPU also contains the HDMA/DMA engines and I/O ports, along with all memory region and chip select logic. If you're familiar with the Amiga, PPU2 is exactly like Denise and PPU1 is most of Agnus with the rest being in the CPU. As far as troubleshooting goes, when you see pixel-width glitches or clock/sync related stuff (like the FIELD flag) it's gonna be PPU2. The FIELD signal comes from PPU2 and is used by PPU1 to know if it should generate the even or odd field in interlace mode. The field flag is just a bit in a PPU register. The failure is because the test is setting interlace mode (you see the converter lose sync when it does) but it never sees the flag change.

@ovalteen4404 Nice work

@@coyote_den Thank you for the explanation. That all makes sense and will no doubt help with repairing some of the other ones here

🥢♨️🍟

How about the 2nd generation snes motherboard 1993 SNS-CPU-GPM-01/02 durable ?

@@playstation2bigs I believe those ones are more reliable in terms of the CPU not dying on them. I had a SHVC-CPU-01 I recapped to try and prolong it's life and after 25 years of service the CPU died on it and I had to landfill it sadly the shell was already brittle and partly broke from age. I still got a SNES jr. that I should RGB amp mod

@@oOignignoktOo1 i also have that 1st gen shvc-cpu-01 japan version from japan. Last year it was working fine, put to storage, this 2024 i fire it up the screen color is dull and wash out then i open it up replace the 6 capacitors near the AV multi out, then power it on to my surprise the screen turns blank or black but there's a game sound. I believe the old capacitor is not the problem but the cpu or the two ppu.