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Graphical Glitches

Discussion in 'Everdrive N8' started by adimifus, Jul 12, 2013.

  1. adimifus

    adimifus <B>Site Supporter 2013</B><BR><B>Site Supporter 20

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    Seemingly out of nowhere, my N8 has been giving me graphical glitches. They're exactly the same every time I try to use it. The glitches carry over to games once their loaded, or the games don't run at all.

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    I tried The Legend of Zelda, Super Mario Bros. 2, and Super Mario Bros. 3. The Mario games didn't run at all, and Zelda had more or less the same issues the menu had. I have a Famicom N8 running through a converter from a Gyromite cart. I took it all apart and checked and cleaned all the contacts. Didn't change anything.
     
  2. wilykat

    wilykat Site Supporter 2013

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    Clean the cart slot, try it with a known good cart. If it still looks the same, you might have a cracked solder or bad trace on the board.
     
  3. adimifus

    adimifus <B>Site Supporter 2013</B><BR><B>Site Supporter 20

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    I should have mentioned regular game carts work fine.
     
  4. MottZilla

    MottZilla Guardian of the Forum

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    It looks like certain pins on the CHR bus aren't connected properly or are shorting out. On the Famicom 60 pin connect these are pins 26 to 30 and 57 to 60 possibly. I doubt it's the NES part since you said regular carts are fine. So open up your cartridge and remove the EverDrive from the adapter and reseat the pcb into the adapter and try again. If it works great, if it doesn't work then try a few more times.
     
  5. adimifus

    adimifus <B>Site Supporter 2013</B><BR><B>Site Supporter 20

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    I put gyromite back into the adapter to see if the adapter was at fault. It runs fine. Put the n8 back in, same exact glitches. I would expect some sort of minute variance in what sort of glitches would happen if it were a dirty contact, but its always exactly the same-- what you see in the pictures I posted.
     
  6. MottZilla

    MottZilla Guardian of the Forum

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    Well without a Famicom or another adapter it's hard to diagnose the issue. However, try pushing the EverDrive pcb to the left or the right in the adapter socket. See if that helps. Again your pictures make it seem *very* likely that just one or more CHR bus lines is not making contact or is getting shorted. It could be happening in the adapter, or it could be the EverDrive itself. However unless you have a Famicom (clone or whatever) to test it on, we can't know for sure.
     
  7. adimifus

    adimifus <B>Site Supporter 2013</B><BR><B>Site Supporter 20

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    Like I said, the original Famicom gyromite PCB still plays fine in the adapter. I had it together in my NES without the shell so I could wiggle everything around to see if anything wasn't tight, and the game was stable.
    Reassembled (and disassembled and reassembled many times) the n8 without the shell so I could wiggle everything around. The glitched image was rock solid. And it never changes. The vertical lines appear on every sprite in Zelda, too. (played on the N8) That also never changes in the slightest.
    I'm worried something happened to the N8 board somehow, because everything else I throw at my NES, with or without the adapter, seems to be working like it should. But like you said, I really don't know for sure unless I can test it without the adapter, but I don't have the means to do that.

    I just checked all the connections between the everdrive's edge contacts and the contacts on the 60 pin side of the adapter board, so the socket in the adapter is fine. And all the traces on the 60 to 72 pin board itself all check out, too.
     
    Last edited: Jul 13, 2013
  8. MottZilla

    MottZilla Guardian of the Forum

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    Mentioning that the lines appear on the sprites too was a good thing. I actually didn't notice that when I first looked at your pictures. It looks like somehow one (or maybe more) signal lines with a CHR BUS address line or data line going to CHR-ROM/CHR-RAM is definitely messed up.

    So you can either send it back to get repaired or replaced, or you could take a look at all the CHR bus signals and see if there is a break in one of the lines. Looking at your picture more closely it looks like CHR D3 is shorted or unconnected. This is pin #29 on the EverDrive pcb. But if you aren't used to dealing with this, sending it to somone to fix it is your only option.
     
  9. adimifus

    adimifus <B>Site Supporter 2013</B><BR><B>Site Supporter 20

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    I didn't notice the lines on the sprites at first, either. They blend in pretty well with the static vertical lines.
    I'm not confident I could actually fix something like this properly, so I think I'm gonna see if I can get it fixed or replaced.
     

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