Help with getting old NES to work - Damn eBay...

[Mangaman_vbulletin3_import15874]

Bought a NES and games off eBay. The guy said "[it] does not load games well" on the page, so I thought a good cleaning of the carts and the inside would solve the probs, like the NES Repair guide suggests. Stupid naive me, the guy sold me a (probable) dud. Still doing that irritating reset-reset-reset thing with the blank screens that change time on every reset. Very irritating - I've spent the last few days working on it to no avail.

So, does anyone have any other ideas? The only thing I haven't done is trying to adjust the pins/whatnot on the cart slot... because I don't understand it 100% ^_^;; Can anyone give some more info on this one or any tips to get this machine up and running? Thanks, I really appreciate it...

-Mangaman-

 

[ExCyber]

If you don't mind getting inside the system, here's an idea:

Open the case.

Take off whatever you need to take off to access the main PCB.

Locate a fairly small chip marked "CIC" on the board. This should have a copyright notice on it.

Disconnect pin 4 of the chip. To locate pin 4, orient the chip so that the dot is on the left. Pin 4 is then the fourth pin from the left on the row closest to you.

This should disable the chip. This is what you want, because the sole purpose of that chip is to make things difficult. Seriously - Nintendo put a chip in the system whose job is to make the system not work unless it detects the correct pseudo-random number stream coming from the cartridge. The SNES and N64 have similar chips, but they're not as much of a problem since SNES and N64 actually have decent cartridge connectors.

I can't guarantee that it will get games runnng, but it's an idea.

 

[Mangaman_vbulletin3_import15874]

Well, I disconnected pin 4. No constant resetting, just an aqua-blue screen. Adjusted the cart slot so it hugs the carts and the PCB firmly, and no change. Looks like it's fruited

Still, thanks for the idea mate - I appreciate it

-Mangaman-

 

[Fabrizo]

I just tried the same thing, but all I get is a red screen. Oh well, I dont use my NES anymore (NesterDC takes care of its job), but it would have still been neat if it had worked.

 

[ExCyber]

Well, you're supposed to connect it to ground, but the doc I read says that it generally works to just disconnect it. The constant resetting thing is supposed to go away when you disable that chip; that's how it stops the system from working, and is why if you e.g. put in a Game Genie with no game, it will appear to run properly but keep resetting (because it has no "key" chip of its own but rather relies on the attached cart).

 

[Mangaman_vbulletin3_import15874]

Quote: from ExCyber on 3:44 am on May 10, 2002
Well, you're supposed to connect it to ground, but the doc I read says that it generally works to just disconnect it. The constant resetting thing is supposed to go away when you disable that chip; that's how it stops the system from working, and is why if you e.g. put in a Game Genie with no game, it will appear to run properly but keep resetting (because it has no "key" chip of its own but rather relies on the attached cart).

Oh, it stopped resetting all right, it just won't load up games. Just a blank screen. My guess is that something on the board has blown, holding up the data transfer. Can't imagine what since the board is in excellent condition.

Any ideas? I think this one's dead

-Mangaman-

 

[ExCyber]

Well, that depends on what kind of test equipment you have access to. If you've got a multimeter and are willing to work on the system live:

Check to make sure that the CPU and PPU are getting power

Check to make sure that pin 22 on the PPU (P/N RP2C02G) and pin 3 on the CPU (P/N RP2A03G) are at a high level (4-5V).

If you have a scope, examine pin 29 of the CPU and pin 18 of the PPU and make sure that a clock signal is present.

Sorry, but that's about all I can think of.

 

[Zziggy00]

Just go to a yard sale and pick another one up for under $5. It'll save you some time.

 

[Raijin Z_vbulletin3_import15802]

Finding working game systems or otherwise at yard sales/discount stores/and the like requires PHENOMENAL luck. I found an NES out on the ass end of Pennsylvania. It works great, but it doesn't display in color most of the time. VERY annoying. The other NES I have works perfectly, so I know it's not my TV or RF switch.

 

[VertigoXX]

Could the connectors be bent? All four of my NES's have that problem. They get old and coil up and won't touch the cartridge. Try loading a game with a Game Genie attached.

 

[Raijin Z_vbulletin3_import15802]

Nothing is physically wrong with the system. Unfortunately, since there is absolutely no repair documentation on the NES, replacing a blown component that might be causing this problem is a no-go.

 

[Nadius]

is there anyway to make an nes less sensitive to shock? I mean i barely tap the thing and the game freezes, or goes to black, i've bent the pins back, so they're really tight to the cartridge, it'll even play when the game isn't locked down, other than that, i don't know what to do.. any help would be appreciated. . .
I'm starting to forget what a new, fully working, optimum condition NES, plays like... and that scares me.

 

[ratfish]

I have the solution here to most of your problems. All you need is a new 72pin cartridge connector. I had the same blinking reset problem, then I installed a new 72pin connector and it works like it did when I first got it back in 1990. You can get this part for $10 plus shipping at the GOAT Store, LLC. That's where I got mine.
http://www.goatstore.com
Hope this works for all of you.