NESRGB install troubleshooting

Are you new to 6502, NES, or even programming in general? Post any of your questions here. Remember - the only dumb question is the question that remains unasked.

Moderator: Moderators

User avatar
Quietust
Posts: 1833
Joined: Sun Sep 19, 2004 10:59 pm
Contact:

Re: NESRGB install troubleshooting

Post by Quietust »

Joe wrote: Fri May 13, 2022 11:09 am
Aerik72 wrote: Fri May 13, 2022 10:50 amunless anybody can eyeball this and point me at a particular PPU pin
Looks more like a loose cartridge than a soldering problem to me. PPU A5 is forced to 1, but the PPU uses a multiplexed bus where A5 and D5 are on the same pin, and I don't see anything wrong with D5. PPU A5 is pin 24 on the cartridge connector.
If PPU A5 was being forced to 1, then the letter "C" would be showing up as "E", "G" would be showing up as "I", and "O" would be showing up as "Q", so clearly there's something else going on.
Quietust, QMT Productions
P.S. If you don't get this note, let me know and I'll write you another.
Aerik72
Posts: 8
Joined: Mon May 09, 2022 11:28 am

Re: NESRGB install troubleshooting

Post by Aerik72 »

Joe wrote: Fri May 13, 2022 11:09 am Looks more like a loose cartridge than a soldering problem to me.
You were right! The remaining graphical glitches were from bad cartridge connection!

I tested Mario, Castlevania 1 & 3, Final Fantasy, Zelda 2, all ok. Then I circled back around to Zelda and with the usual finagling and retries I got it working perfectly!

From here I just need to do some cleaning, and then I'm good to go.

Fiskbit, you're the hero of Hyrule for pointing me at the main issue, but thank you everybody who responded! :) :)
Fiskbit
Posts: 428
Joined: Sat Nov 18, 2017 9:15 pm

Re: NESRGB install troubleshooting

Post by Fiskbit »

Looks like Joe actually identified the problem first (open bus and pin 24), though I didn't realize at the time he meant PPU /RD. Glad you got it working!
Post Reply