1st player port continues to move up

[Cholkavich]

Today i decided to fire up my model 1 to play some ms pacman. I start the game and she continues to go up. first i thought it to be my controller, nope its the system. I tried a bunch of games and controllers. Im really bummed out cuz this is my s-video HDG model . Only port 1 has this issue, port 2 is fine. Any ideas how to fix this?

[Lastcallhall]

Resolder the controller port pins. That usually does the trick.

[Guntz]

If you're not sure how to do that, basically all you're doing is heating the solder pads until they become liquid, then let them cool again. That's called reflowing. You way want to add a bit of extra solder/flux to help the solder bond better.

[Cholkavich]

ok cool thanks guys, ill take a whack at it soon.

[Guntz]

ok cool thanks guys, ill take a whack at it soon.

*looks at your avatar*

I see what you did there...

[ApolloBoy]

Yep, definitely sounds like the controller port pins need to be reflowed. Just heat them up and add a pinch more solder and that should fix your problem.

[goldenband]

Today i decided to fire up my model 1 to play some ms pacman. I start the game and she continues to go up. first i thought it to be my controller, nope its the system. I tried a bunch of games and controllers.

I'm glad you mentioned that last part, since Ms. Pac-Man is incompatible with 6-button controllers. Wouldn't want you resoldering things on account of that, though I don't remember whether the Ms. goes straight up or does something else.

[KnightWarrior]

Ms Pac Man dosen't go up with the 6 button Pad

[Cholkavich]

ok so i took my model 1 apart and reflowed the solder on the first controller port. I waited for the solder to cool. tried it out and still having the same problem. this time i tried a bunch of fighting games like mortal kombat 2 & 3, super street fighter, street fighter CE. i tried a 6 button controller, a 3 button, and official wireless controllers. same damn problem. any ideas?

[gamevet]

It's either the I/O controller chip used for the DB9 connectors, or one of those black (I can't tell what those are) devices between the DB9 and the chip. You'll have to find out which pin is up, on the controller port, and might try exchanging it with the same one on the 2nd port.

http://s685.photobucket.com/albums/v...sort=ascending

http://segaretro.org/Control_Pad_(Mega_Drive)

It's pin one of your DB9 connection. You might want to look at this chart, to determine which pin it connects to in the I/O chip. It could be a simple fix, that requires a reflow of that pin on the I/O chip.

*Edit* I believe those black devices between the DB9 and the I/O chip are 10K resistors. You may have a bad resistor to either pins 1 or 2 between the DB9 and the I/O chip. Try tracing the circuit on the underside of the board, from pin connections 1 and 2, to where they connect to the I/O chip.

[Cholkavich]

is it possible to fry the input through a static charge. the reason i ask is because my CRT tv produces static when its on and my genesis sits on top. im wondering if its possible that static had built up on the controller cable? either way i cant seem to fix this and its bumming me out.

[Chibisteven]

is it possible to fry the input through a static charge. the reason i ask is because my CRT tv produces static when its on and my genesis sits on top. im wondering if its possible that static had built up on the controller cable? either way i cant seem to fix this and its bumming me out.

That's something I wouldn't do. I don't know if CRT screen would be enough static charge to penetrate a rubber wire. You would of had to have discharge at the port with your hand or something.

The input would be toast if the I/O chip is damaged from a charge (how much I don't know but I wouldn't risk it before frying an eternal connection). Any kids playing with Genesis power cords and controller ports? Most likely that would blow out the whole button the pin respents and you would get no movement after a button press typically.

I look at a fuse on the circuit by the port if that's what those things are (they seem to be for each input).

[gamevet]

I look at a fuse on the circuit by the port if that's what those things are (they seem to be for each input).

Those are 10k resisters. They'll help absorb any static electricity generated from outside sources. Setting a Genesis on carpet would do just as much damage.

I suggest taking a small pick, or a pen head, and using it to lightly tap each pin (underside of the board) on the I/O chip. It is possible that it could have a loose solder joint there. I've circled the chips in the picture.

[Cholkavich]

ok so i went and reflowed solder on every point in the area you circled and still no luck.

[MEGADRIVE Jeroi]

Your problem is the controller. Or is it same really with all controllers? Does the controller act like that in second port also?

I have fixed old 3 button controllers many times. They have this horrible desing where there is plastiC stick againts the controller back panel. This stick wears in time and suddenly controller starts to have those problems of yours or not moving correctly the at all. Fixed many times these with cardboard paper attached between controller and that stick to get more solid contacting again.

How ever the if controller keeps going up, it means usually different controller version where usual problem is your silicon rubber broken on your pad. Replacing that cost arround few dollars on ebay.

I have not yet seen a problem with control port but as everyone has told reflowing and checking with multimeter that there is not 5v short-circuit to some of those lines.

How ever usually this problem is caused by oooooooooold and haaaaaaaard used Joypad (because Genesis is just damn good).