Need help to get my NES clone to work properly

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Need help to get my NES clone to work properly
by on (#107377)
I bought an NES clone from the bazar for 3€ on a pile of rubbish :D
I went home and opened it to see if there are any shorts or defects on it, but it did not seem like it.
As I do not own a proper adapter to power the clone I connected a battery to power it (the clone needs 9V to work)
For some time it played really well, also NTSC games that did not work on my PAL NES showed the sprites in proper order. But then it went crazy and now it only shows wrong sprites. The game mechanics and music is working like it should.
The clone is a SUPER COM 72 and has 1000000in1 games already built in(just a famicom sized 60pin cart soldered to the clone and a chip that acts like a switch for switching to the inserted cart if there is one inserted.
I hope it is nothing to bad, so I can fix. If anybody can do something with the information I shared on this and is able to help me out with that, I would be really happy :)
Thanks in advance.

Ps: if needed I can provide more pictures.
Re: Need help to get my NES clone to work properly
by on (#107386)
You should try to find a suitable adapter for it and retest it.
Re: Need help to get my NES clone to work properly
by on (#107397)
Are you still powering it off battery power? Maybe the battery voltage dipped too low. Also, does the built in multi-cart have the graphics problems, or just inserted cartridges?
Re: Need help to get my NES clone to work properly
by on (#107398)
lol i have the same problem in my 90's famiclone. fully glitched in all carts i use to test it.
sometimes i get glitches with graphic corruptions (a-la poor connections in chr pins) but when i hold reset... this corruption is gone.

http://www.youtube.com/watch?v=A9AmAhgH0OM
a video example showing this unusual famicom issue. using a bootleg rockman 4.

smb runs a little bit slow (for example when there are many enemies on the screen)

CPU and PPU are OK cuz i use two fresh and legit NES ICs that are replacing old clones

note: 2a03 gets hot in 2 seconds yay
Re: Need help to get my NES clone to work properly
by on (#107399)
I used new batteries to see if the voltage was too low, but no luck. All carts, also the built in, have the problem with graphics. I will try to get a suitable adapter, but as I said before, it worked with the battery without issues for some time.
Re: Need help to get my NES clone to work properly
by on (#107400)
Snacks wrote:
lol i have the same problem in my 90's famiclone. fully glitched in all carts i use to test it.
sometimes i get glitches with graphic corruptions (a-la poor connections in chr pins) but when i hold reset... this corruption is gone.

http://www.youtube.com/watch?v=A9AmAhgH0OM
a video example showing this unusual famicom issue. using a bootleg rockman 4.

smb runs a little bit slow (for example when there are many enemies on the screen)

CPU and PPU are OK cuz i use two fresh and legit NES ICs that are replacing old clones

note: 2a03 gets hot in 2 seconds yay


Ok i will also try it with reset, I did not before because the reset button was broken and i thought it is unnecessary anyways. i should also mention that this is a nes-on-a-chip console, so i can not just replace the chip.
Re: Need help to get my NES clone to work properly
by on (#107403)
Snacks wrote:
lol i have the same problem in my 90's famiclone. fully glitched in all carts i use to test it.
sometimes i get glitches with graphic corruptions (a-la poor connections in chr pins) but when i hold reset... this corruption is gone.

http://www.youtube.com/watch?v=A9AmAhgH0OM
a video example showing this unusual famicom issue. using a bootleg rockman 4.

smb runs a little bit slow (for example when there are many enemies on the screen)

CPU and PPU are OK cuz i use two fresh and legit NES ICs that are replacing old clones

note: 2a03 gets hot in 2 seconds yay


Wow, that's pretty impressive, looks like the nametables are some function of the address lines, and completely ignore the internal video RAM. Maybe there's some bad connections for the lines that enable the internal video RAM, select mirroring, or something like that. Sprites look normal.
Re: Need help to get my NES clone to work properly
by on (#107405)
elseyf wrote:
i should also mention that this is a nes-on-a-chip console, so i can not just replace the chip.

your internal game card presents the same glitches. it means you should to check for broken tracks between NOAC and internal game card.
Re: Need help to get my NES clone to work properly
by on (#107410)
I had no luck with a power adapter. I also removed the internal game to look if there was any issue with it, but no luck, the graphics look the same. I tested all traces I could and it seemed like there were no bad connections or shorts. Are there any other suggestions?
Also a pic of the NOAC Board:
Re: Need help to get my NES clone to work properly
by on (#107413)
As far as I can tell, it looks like the patterns might be coming from the wrong bank? Maybe? Do you have any plain NROM games to test? I'd also be curious if games with CHR-RAM have more severe corruption. (It looks like all three games you've tested have CHR-ROM)
Re: Need help to get my NES clone to work properly
by on (#107416)
Here is excite bike and zelda 1
Re: Need help to get my NES clone to work properly
by on (#107419)
Huh, that's kinda useful.

Comparing what Excitebike's title screen says to what it should:
Code:
SUKUSSIOM Q / SUKUSSIOM Q / SUSIGM / GOOK MIMSUMSO
SELECTION A / SELECTION B / DESIGN / 1984 NINTENDO
Correspondingly, the alphanumerics in this game are just 0-9,A-Z in order. So we can see what the difference is...
Code:
-40440--0 4 / -40440--0 ! / !4---0 / !!44 0-00404-
key: - = no difference 
0 = 2⁰ bit erroneously cleared
4 = 2⁴ bit erroneously set
! = both of above
But there's nothing wrong with the palette, and the CHR-RAM game isn't any more corrupt, which implies this isn't the data bus, but is the PPU's address bus.

Huh, and PPU A4 and A8 are opposite from each other. My best guess is you've either got some shorted pins, disconnected pins, or damaged drivers on this pins. The first two should be fixable...
Re: Need help to get my NES clone to work properly
by on (#107420)
Wow, your clone has quite the racist copyright message!
Re: Need help to get my NES clone to work properly
by on (#107429)
So then he should refer to the pinout here. http://wiki.nesdev.com/w/index.php/Cartridge_connector

And check for a short between CHR A4 and CHR A8, pins 21 and 51, or if either is disconnected.
Re: Need help to get my NES clone to work properly
by on (#107443)
I checked all tracks and components on the board (also investigated A4 and A8 connection of the NOAC), all are fine, I think the NOAC is fried up whyever because there is nothing broken, I also changed the components with exception to the clock (the thing labeled with 26.6017mhz)
I give up, I will desolder the Connector of the NESclone and solder it to my Famiclone, so it has 60 and 72 pin connectors.
Anyways thanks for the suggestions.