>BTW, if the fuse blows, the joystick will still work. The >fuse only protects the 5V. The 5v powers the mouse, but >joysticks don't need it. If you have a voltmeter, check >between the middle two pins on the bottom row of either port. >Back when I was a service guy, i built a tester by putting an >LED and 200 ohm resistor (observing polarity) across those >two pins on a DB9 plug... easier than a meter.
...
Thanks for pointing out where the fuse is. I have an A2500 with that problem-- joystick works but mouse does not. However, for the non-technically inclined, I would recommend trying the following simulation cable to isolate if it's the 5V problem:
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=320141348186If the simulated mouse works and the real mouse does not, you know it's the 5V problem.