Hi there! I'm new to the site so apologies if this is the wrong place to be asking this, but I've got a few questions about my GameShark.

So I recently came into possession of a used v3.3 GameShark Pro for Nintendo 64. I was really looking forward to trying out a bunch of cheats! So I try it out, and it seemed to work perfectly. The menu loads properly, the games seem to all be compatible, the cheats work correctly, and everything seemed to be working fine. However, I came across a very concerning issue that makes me afraid to even try using my GameShark any further.

So I was trying Banjo-Kazooie with my GameShark and everything was working just fine. I turn off my console and put another game into the GameShark to try out. I turn on my console and... black screen. I try a few more games only to get the same black screen. So I gave up with the GameShark and decided I'll just come back to it later, and put a game in without the GameShark to play it normally. Concerningly, it still had a black screen. I began to get nervous, so I tried a few more games without the GameShark to no avail.

I began to panic, so I got a game off my shelf that I hadn't even put in my GameShark or console recently, and sure enough, the game powered on normally. After that, I retried my other games and they worked properly again. Tried a few of them with the GameShark and, once again, loaded the menu just fine.

This was a relief. Thought I may have just triggered some weird system error or something and that it'd likely not happen again. So, I went back to try games with the GameShark. This time, I tried Super Mario 64 with a very simple cheat; the debug menu. Started the game, cheat worked perfectly, game ran fine, everything seemed alright. Turn the console off again to try another game, turn it back on and... black screen once again. Try Mario 64 without the GameShark and still black screen. Tried the same game that had fixed the issue before (Bomberman 64, if I remember correctly) and, surprisingly, STILL a black screen. This left me scratching my head because I hadn't even put that game into the GameShark at all. I went back to my shelf and got another game that I hadn't played in a while; PilotWings 64. Sure enough, it powered on just fine, and afterwards so did all my other games.

Now I was really becoming confused. I decided to try one last test. This time, I tried Mario 64 with the debug code once again, powered off the console, and instead of trying another game in the GameShark, I tried Ocarina of Time, another game that was on my shelf and hadn't used recently, without the GameShark. Turn it on and... nothing. Black screen. I try more games from my shelf that I hadn't used in a while to try and fix the issue and even some of those weren't even working. Eventually I tried Donkey Kong 64, and that thankfully fixed the issue once more. I haven't tried using the GameShark since.

So my question is... what is going on? Am I doing something wrong? Is my GameShark faulty, or perhaps my console? I am very confused as to what is going on, so any insight would be greatly appreciated.

For further details, my console is a Jungle Green N64 with an official expansion pack, official power cable, and a 3rd party S-Video cable. I was also using a CRT TV, if that matters at all.

Thank you all in advance!

You said you got a black screen with a normal game too, without GS. That means it's the console.

Most likely it's the cart slot. Clean it.

^ Also keep pushing the carts in and out of the slots a few times before turning it on after cleaning. That will help seat the contacts in case there was any gunk on them.

Alright, I used a 1-Up Card N64 Console Cleaner to clean the pins on my console and GameShark, since I don't trust myself to clean the pins by hand. It did clearly pick up a lot of grime, but it didn't solve my issue. I'm still having this weird glitch that prevents the console from starting games after using the GameShark. I don't know if the 1-Up card just didn't clean them sufficiently, or if that isn't the issue at all.
Just for the record, I have cleaned my GameShark's bottom contacts, as well as the contacts on all my N64 games. Any further suggestions as to what I should do would be greatly appreciated.

Im not sure how high quality the n64 gameshark is but it could have damaged the pins themselves. With unlicensed/bootleg items they dont always fit well and can ruin the cart slot. Thats how i ruined my NES. Does it fit well in the slot?

Yes, it seems to fit quite well. In fact, it seems to pop in just as easy as an official cart. Problem is after I use it with a game for some reason, the console just doesn’t want to run anything until I find one working game, then everything is back to normal. I’m not sure why this is

 

I would suggest it's probably just some dirty pins and connectors. That whole black screen issue is simply the lack of the N64 recognizing that a cart has been inserted, which is common with older systems and games. It is not, to my knowledge, possible to alter the internal system of the N64 itself: as soon as you cut the power it will return to its original internal configuration no matter what you were doing with it while it was on.

The thing is, different games may have grime or corrosion in different spots on their pins, or different amounts that would effect each game differently. That's why some games would work straight away and some would not. The Game Shark may have been dirty before you put it in the system, and deposited grime on to the pin connectors. This would then effect subsequent games.

I see you say you have now cleaned the games and the system, but it is possible that there was some nasty grime that hasn't yet been cleaned and is still in your N64 pin connector or on the carts. I would suggest re-cleaning each part thoroughly, and continually re-inserting a game into the slot until it plays properly, which should dislodge whatever's in there. I have had clean games that still required multiple insertions to get running, because there was probably an invisible layer of corrosion in the wrong spot that interrupted the connection between the game and the system.

Of course, it is impossible to rule out the chance that the connector itself is damaged somehow... But I am not getting that from what you are describing, and it would probably be the first I've heard of something like that happening to an N64.

Alright, it's been quite a while, but I have confirmed this is an issue with my console. I tested the GameShark out on a friend's N64 and it worked perfectly. No glitches or errors. I used my same carts and cables for testing it, too. It's extremely strange. I'm not sure how this is happening with my console in particular, and specifically AFTER using the GameShark, causing specific games to not work until playing another.

I don't even know if this is possible, but I have to assume this is some sort of rare system error, because if it had to do to with the pins I don't think they would be bent out of place specifically after playing a game with the GameShark and not just inserting it into the console.

Again, I have a Jungle Green N64. I doubt that has anything to do with it, but my friend does have just a standard gray N64 which we used for testing. If anyone has any idea how or why this is happening, please let me know.

Strange. Almost like the Gameshark is setting something with the N64's PIF chip that makes it seize until it sees the specific boot CIC it expects.

I used this list back in the day with my Doctor V64 to figure out which cartridges I could use to boot a particular game loaded into the unit's DRAM:
http://n64.icequake.net/mirror/ww...

Maybe you can assemble a set of carts for each CIC and go through each one to see if a particular CIC knocks it out of the locked-up state.

For USA region...

6102
Most common. Used by early 1st/2nd party games and nearly all third party games.

6101
Star Fox 64

6103 
1080° Snowboarding
Banjo-Kazooie
Diddy Kong Racing
Excitebike 64
Ken Griffey Jr's Slugfest
Kirby 64 The Crystal Shards
Kobe Bryant in NBA Courtside
Major League Baseball featuring Ken Griffey Jr
Pokémon Snap
Pokémon Stadium
Super Smash Bros

6105
Banjo-Tooie
Donkey Kong 64
Jet Force Gemini
Zelda Ocarina of Time
Zelda Majora's Mask
Mickey's Speedway USA
Perfect Dark

6106
Yoshi's Story
Cruisn' World
F-Zero X

I'm leaning towards agreeing about the CIC fix. I guess there could be some hard funk somewhere but this seems almost more like a security trip out effect here. Going to certain games each time on differing CICs seemed to have resolved the lockout state.

3.3 is finicky. To get it to work sometimes you have to use specific games to "reboot" the thing. You triggered this most likely. Once you retried it and reset it, it went back to normal.


 Common issue. You have to use different games to reboot it to load around thatn64 chip. Diddy kong racing was another common game to get it working again

http://atariage.com/forums/topic/132541-some-help-with-my-ne...

That wouldn’t have any bearing on his ability to boot without it though.

Also, it's by design (intentional) that you can't boot without the correct CIC. If I recall correctly, after changing the GameShark boot key to a particular CIC, you need to have one of those games around or you will not be able to boot the GameShark again to change modes.

Its probably just coincidence. Probably had a blemish in the pin area after gameshark was in there. Rebooting gameshark probably cleared the blemish on the pins. 

This is my vote. You will definitely get a stuck black screen if you boot the Gameshark using a key that you don't have a matching cart for. That's why there's a warning whenever you go to change it. 
 

Have you tried a different power supply? Sometimes they do funky stuff to N64 games.

I don't quite understand the explanation here. How does the N64 keep memory of which CIC the game shark failed to boot with after it's been turned off? And also, why would that then also prevent the N64 from loading the next game when not using the game shark?

I don't think it can but I've seen MarshallH and Co's decapping and analysis of the PIF chip and it looks like there's a lot of crazy unexpected stuff going on in there. It has ROM, a CPU, the counterpart to the CICs, etc.

This was the presentation where they discussed reverse engineering the CICs. Even though they released the CIC code for each clone CIC their analysis actually led to a method to make a universal CIC, which they kept to themselves. MarshallH's own 64Drive uses this but the code is built-in to the FPGA used for the rest of the functions and can't be used elsewhere.