Search found 79 matches

by jcarlos
Wed Nov 23, 2022 5:19 pm
Forum: SNESdev
Topic: Wrong SNES video
Replies: 19
Views: 1248

Re: Wrong SNES video

Here I have the electrical diagram of the snes. It is seen that PPU1 is the one that addresses the video memories and not PPU2.
by jcarlos
Wed Nov 23, 2022 5:10 pm
Forum: SNESdev
Topic: Wrong SNES video
Replies: 19
Views: 1248

Re: Wrong SNES video

And the working RAM of 128K, I have not replaced this, could it be the cause?
by jcarlos
Wed Nov 23, 2022 4:38 pm
Forum: SNESdev
Topic: Wrong SNES video
Replies: 19
Views: 1248

Re: Wrong SNES video

What is more likely that the failure is in the PPU1 or the PPU2?
by jcarlos
Wed Nov 23, 2022 4:35 pm
Forum: SNESdev
Topic: Wrong SNES video
Replies: 19
Views: 1248

Re: Wrong SNES video

I already replaced both video RAM memories and nothing continues the problem. Thank you
by jcarlos
Wed Nov 23, 2022 1:14 pm
Forum: SNESdev
Topic: Wrong SNES video
Replies: 19
Views: 1248

Re: Wrong SNES video

Looks like problems between the PPU and the video memory, like some address lines aren't connected properly. Or it could be a problem where the PPU has an error inside of it where it's picking the wrong address to fetch tiles from. Good. I have reviewed, I think all the connections, between the PPU...
by jcarlos
Wed Nov 23, 2022 1:13 pm
Forum: SNESdev
Topic: Wrong SNES video
Replies: 19
Views: 1248

Re: Wrong SNES video

Good. I have reviewed, I think all the connections, between the PPU1 and the video memories and some more connections, but everything seems to be OK. I think that surely, as Dwedit said, it will be some integrated circuit like the PPU1, but I don't know which one, I have spare parts for all of them ...
by jcarlos
Sat Dec 25, 2021 9:56 pm
Forum: SNESdev
Topic: Wrong SNES video
Replies: 19
Views: 1248

Re: Wrong SNES video

So I can't see a bug in the PPU?
by jcarlos
Sat Dec 25, 2021 11:55 am
Forum: SNESdev
Topic: Wrong SNES video
Replies: 19
Views: 1248

Re: Wrong SNES video

I have asked for the Super NES burn-in Test, I don't know if I will be able to see that it fails. My question is if what fails is the PPU1, will it mark it for me in the last test where it says APU?
by jcarlos
Fri Dec 24, 2021 7:41 pm
Forum: SNESdev
Topic: Wrong SNES video
Replies: 19
Views: 1248

Re: Wrong SNES video

I have replaced both 32K bytes U4 and U5 memories and I get the same result, exactly the same images. I think the next one to replace is the PPU1, which is the one that communicates with the memories, but for this I am going to buy a hot air station. I've seen one at a good price.
by jcarlos
Thu Dec 23, 2021 5:50 am
Forum: SNESdev
Topic: Wrong SNES video
Replies: 19
Views: 1248

Re: Wrong SNES video

I already have parts for the SNES. I have got two plates at a low price that did not work, one does not turn on, does not give any signal and the other black screen. I could risk changing the memory of the PPU1 seems easier than the PPU itself, since I do it without a hot air station, but with solde...
by jcarlos
Tue Dec 21, 2021 8:47 pm
Forum: SNESdev
Topic: Wrong SNES video
Replies: 19
Views: 1248

Re: Wrong SNES video

The problem is that I do not have a hot air station to desolder the components. I only have a 25W soldering iron and a 15W soldering iron. I don't know if that is enough.
by jcarlos
Tue Dec 21, 2021 1:17 pm
Forum: SNESdev
Topic: Wrong SNES video
Replies: 19
Views: 1248

Re: Wrong SNES video

I have continuously tested the address and data connections of the PPU with the memories and everything seems correct.
by jcarlos
Mon Dec 20, 2021 12:08 pm
Forum: SNESdev
Topic: Wrong SNES video
Replies: 19
Views: 1248

Wrong SNES video

Hi, I have a SNES PAL that gives me errors in the video. Attached image. Anyone know what can happen. Thanks
by jcarlos
Sat Apr 03, 2021 9:25 pm
Forum: NES Hardware and Flash Equipment
Topic: NES-001 cap replacement guide for the av power module
Replies: 114
Views: 66905

Re: NES-001 cap replacement guide for the av power module

Indeed, it was pin A1 that goes from the PPU (pin 37) to the 74LS373 (pin 13), there was a bad connection, I put a jumper and that's it. She wanted to thank him for her essential help, without her she could not have done it. Thank you.
by jcarlos
Sun Mar 28, 2021 2:10 pm
Forum: NES Hardware and Flash Equipment
Topic: NES-001 cap replacement guide for the av power module
Replies: 114
Views: 66905

Re: NES-001 cap replacement guide for the av power module

I have measured continuity of both AD2 and ALE and they arrive at the 74LS373, it seems that the connection failure is not. Could it be that this input is faulty and latches are not enabled with the ALE signal?