MFM1%LEHIGH.BITNET@ibm1.cc.lehigh.edu (mark masters) (01/13/89)
Rob, I tried to email you earlier, but I don't know if it got through and I wasn't very clear. I don't think your problem is in the 8520 chip, so don't go messing with it right away. I think the problem lies with the chip which your joysticks attach to directly. I know this can be disturbing and frightening as I had the same experience on mouse/joy port 1. You can blow out only one of the inputs on this chip. I did it on my 2000, same simptoms as yours but the left direction was always on. To make it worse, this causes the mouse to stop functioning as well. In the Amiga 500 this chip is U15 a 74LS157. It is soldered to the motherboard very near the joystick inputs. I desoldered mine and replaced it with a socket and a new chip (make sure it is LS or else all sorts of strange things happen). If you do solder on the mother board be sure to use a low wattage soldering iron, less than 20 watts. If you are frightened, then best to allow someone with experience do replace it. Be sure to have a socket put in place, in case of repeat repairs. Of course doing this voids your warenty. BTW, 74LS157 chips cost all of $.12 from Jameco. Hope this helps, and good luck mark <mfm1@lehigh.bitnet>