USB Gamepad keeps locking up.

[markb]

I've just built a small arcade machine for a friends son using some left over components and an old Compaq PII 300mhz. I bought a cheap PC USB gamepad along the lines of a playstation pad (2 axes, 10 buttons) and used it to wire up the arcade stick and 8 buttons. 4 of the buttons are for games the other 4 are for Mame32 functions ie Escape, credit etc.

I've tested all of the connections with a multi-meter and everything is okay, the wires are all solidly connected and soldered but I am having some problems, every few minutes the joystick 'locks' up.  This can be during a game, or running the test program and it can be when only the joystick is being used with no buttons being pressed.
The joystick still registers as okay on the control panel however no button can be used. Unplugging it from the USB port then putting it back in causes the joystick to spring back into life.

Is this a common problem? can only so many buttons be wired into a USB port? I have also tried the exact same PC USB pad unhacked and have so far been unable to lock that one up which is why I wonder if there is something wrong with hacking that many buttons.

Any help would be appreciated as I am pretty much stuck at the moment.

Thanks

[Bgnome]

i would suspect some sort of powering issue.  you may have a short circuit somewhere.  did you have any problems with the pad prior to hacking?  the number of buttons hacked shouldnt be a problem if they were all supported by the pad in the first place.  what pad is it?  are you using the generic HID compliant windows drivers or specific gamepad drivers?  i do recall an issue with gravis gamepads hacks in particular but i have not dealt with them personally..

[markb]

The joypad is a generic HID and worked no problems for 6 months prior to it being hacked. It has no drivers and is picked up by Windows 98SE no problems. I've checked for shorts but I'm going to have another look just in case.