SERIOUS ISSUE - Extending Cart Connector

[vomitsaw]

Okay, I'm noticing a trend. So far I've run into the same problem FOUR times now on different occasions, different projects and different consoles. This seems to be a serious issue and something to consider/look into, probably sticky-worthy if we're able to confirm it even. ...Either that or I have some of the worst luck in the world. Or I'm an idiot. We'll see. Read on.

The problem? Certain games glitching/freezing randomly when played via an EXTENDED cartridge connector. (Relocated with X-inches of wire to accommodate case design, etc.)

On the SNES, I've noticed that Super Mario World 2 likes to randomly crap out within 5-15 minutes of play on an extended connector. This is the second occasion in which I've noticed this issue. (Happened to me while working on the Super Genintari too).

On the NES, I've noticed that Tengen Tetris develops strange graphical artifacts usually within seconds when being plugged into an extended connector, and Abadox will usually completely freeze within the first minute or two. (Again, this happened on two or three completely separate occasions).

Otherwise, these games work perfectly fine on unaltered cart connectors. Continuity on the wires is fine. Nothing's touching, sufficient power is supplied and I've tried multiple different types of wires. Only after re-doing the wiring several times do I seem to randomly find some kind of "sweet spot" where all the games will work.

Can anyone else confirm this for me? Super Mario World 2 seems to be an excellent test game for modded SNES machines. Can you play past 10 minutes or so without some kind of glitching? And if so, is your save game retained upon restart?

This issue has me completely confused and pulling my hair out. There MUST be something to it. Something I haven't figured out yet. Has anyone else experienced similar issues? Do you even know what I'm yammering on about? Please share. Trying to figure this one out.

PS: Please don't reply with generic comments like "check your wiring". I've done that, I'm not retarded.

[XCVG]

What about using thicker wires? Perhaps the thinner wires have too much resistance.

[Rekarp]

Yep the Sega Neptune V1 has serious issues just like that. In V2 I cut the wire length from 4" to 1" and solved all the problems. What is happening is consoles where only designed for the signal to go so far. Extending it really pushes the limit of what the interface is capable for. The easiest way to fix this is to make the wires shorter, use solid wire, use thicker wires.

When you extend the cart slot you are adding more inductance, resistance, and interference to the interface.

[vomitsaw]

Yeah, it's definitely something to do with the wires, but WHAT I have yet to nail down. First I was using about 8" of your standard IDE ribbon cable to do the job and I noticed glitching very early. (Within the first 3 minutes or so). Then I changed the wires to a solid copper speaker wires (not TOO thick, but a little thicker than standard IDE ribbon cable). And believe it or not, I currently have the game DIRECTLY SOLDERED to the wire. I'm getting the same glitching but it seems to take a little longer to happen now. (Maybe 5-10 minutes).

Next thing I'm gonna try is to HALF the length of the wires and see how much of a difference that makes. Oddly enough, last time I got this to work I ended up using those TINY IDE ribbon cables. (The 80-conductor stuff). It just seems like there are a couple of EXTREMELY sensitive signals that don't like to be extended. Exactly which ones I'm not sure, but eager to find out.

Thanks everyone for your input so far. I'll keep this thread updated as I discover new things.

[Rekarp]

8"? Thats very long. For portables mine rarely exceed 3".

[vomitsaw]

8"? Thats very long. For portables mine rarely exceed 3".

Yeah, it IS a bit long, but there's not much I can do about it unfortunately. I might be able to get it down around 5" but it'll be difficult. The casing requires that I twist the connector 90 degrees one direction, then 90 degrees another. All that twisting and turning tends to eat up some length. :/ I've gotten it to work before though, that's the thing that bugs me. Wish I knew exactly which signals were the sensitive ones.

[Metroid fan]

Yeah my snes mini has approximately 6 inch ide cable wires and games don't even work. So I'm going to shorten the wires by about half and hope that it works.

[vomitsaw]

Okay, so I shortened the same exact wires by about 3 inches, re-soldered to the game and to my surprise it was glitch-free! I'm not in the clear yet though. Just finished re-attaching the cart connector and am currently testing that way. Only about 5 minutes into it so far, keeping my fingers crossed.

[nevermind1534]

Okay, so I shortened the same exact wires by about 3 inches, re-soldered to the game and to my surprise it was glitch-free! I'm not in the clear yet though. Just finished re-attaching the cart connector and am currently testing that way. Only about 5 minutes into it so far, keeping my fingers crossed.

I hope it works out for you.

[vomitsaw]

Okay, so I shortened the same exact wires by about 3 inches, re-soldered to the game and to my surprise it was glitch-free! I'm not in the clear yet though. Just finished re-attaching the cart connector and am currently testing that way. Only about 5 minutes into it so far, keeping my fingers crossed.

I hope it works out for you.

Thanks. Turns out it DID work fine, but the wires are just too darn thick/rigid for me to work with. Having an extremely difficult time positioning the cart connector inside the case. Soooo, looks like I've gonna have to use some thinner cabling. ...And test it all over again.

[themadhacker]

Well, my retro duo portable WIP has the cart connector rlocated with about 2 inches of copper wire. After reading this I got a bit wary, so I decided to test out some games. I played mario world for about 2o minutes without any problems, then super mario kart for about 12 minutes without problems. So it seems like I am safe (knock on wood)

[Triton]

good rule of thumb is to keep all wires as short as reasonably possible to prevent interference and signal degradation. in my case i keep it short because of the utter lack of room!

thats the 80 conductor ribbon cable, works AWESOME, will be using it in my gp2x because its not much bigger and MUCH easier to work with than 34 gauge enamel wire the shorter wires are around half an inch with the longer ones being maybe an inch and change

[vomitsaw]

good rule of thumb is to keep all wires as short as reasonably possible to prevent interference and signal degradation. in my case i keep it short because of the utter lack of room!

thats the 80 conductor ribbon cable, works AWESOME, will be using it in my gp2x because its not much bigger and MUCH easier to work with than 34 gauge enamel wire the shorter wires are around half an inch with the longer ones being maybe an inch and change

Ah nice! Yeah, doesn't that 80-conductor stuff rock? Super small, easy to work with, solid copper on the inside. Just a little tricky to strip at times. (Have to use my teeth).
Anyhow, rewired again with the 80-conductor stuff and was able to play through Metroid 3 from start to finish without a single problem. Super Mario World 2, however, still has issues. Now it seems to wanna crash during the boss battle in world 1. (The big blob). Done it twice in a row now, same spot. Strange. Seems that games is EXTREMELY picky about the wiring, because every time it's changed, it likes to glitch in different places. Not gonna lose sleep over it though. All other games seem to work perfectly fine. :/

[asdfjkl;]

maybe the glitch is in your game?

[vomitsaw]

maybe the glitch is in your game?

I've thought about that, I suppose it's possible but I kinda doubt it. Changing the wire type and length seems to be controlling the glitching a little too precisely. That and I've been able to play though the entire game before on an unaltered system. I'm willing to bet that there's just something about this game, something to do with certain specific signals coming off of it that are extremely sensitive to the connector wiring. Just don't have any definitive proof yet.