A2000 mouse port dead

[dbrads]

Hi All,

 My A2000 mouse port has died, the pins are fine and I have tried 2 different mice that are OK on my A1200 so it must be something on the MB.

Any suggestions?

[B00tDisk]

Bad CIA chip.  Does the other port work?  Have you tried a joystick in that port?

[orange]

if you're lucky it could be the fuse (IIRC)
also check the voltage

[gazgod]

I have had a fuse blow on my 2000, the following is from a post on the newtech forums which helped me fix mine :-

2) On the later model Amiga 2000 systems this is usually due to a blown fuse, F1, on the A2000 motherboard, though the port controller chip is also a possibility; early A2000 revisions did not have the fuse, so the chip is definitely the source of failure. For other models, it may be a similar fuse if such exists, or the port controller chip. Static can blow the fuse or chip, but an attempt to use an incorrectly wired GPI cable on the joystick port is another common cause.

On those models with a fuse, the fuse must be replaced, and is a soldered-in component that looks like a resistor, but is green in color. The component is located right behind the mouse and joystick ports. You will most likely wish to have a service center do the repair.
(from http://www.newtek.com/forums/showthread.php?t=6899&goto=nextoldest)
Gaz

http://www.lincsamiga.org.uk

[orange]

It is called "picofuse" the same one is used for voltage on video out and other connectors. unfortunately it costs a lot more than ordinary fuse.
I was surprised to see its rated at 4A (IIRC), seems a bit too high..

[amigakid]

You might want to check the solder joints also.  i had one on my A500?? i think the mouse got jerked out and it broke a solder joint.

[dbrads]

Thanks for the replies guys,

I have replaced the CIA chip but no joy, I have a rev6.0 board and can not see a "green fuse" so it must be something else.

 I will e-check the pins and solder.

  PS, The buttons work :-?

[dbrads]

I have looked at the mother board, cant find a fuse F1.

Looking at the schematic the fuse is for both ports but the joystick is OK so it cant be that, the port control chip (U202) must be Ok too.

What are the small blue items behind the ports, could one of these be the problem?

[HellCoder]

I've got problems with my mouseport too. There is a program somewere on Aminet to swap the two ports. I'm now using my mouse in the other port. I'm not at home and can't recall the name of the patch but it shouldn't be hard to find ?

[Jupp3]

You might want to check the solder joints also.

Indeed, I had that problem with the joystick port in my A2000. After heating solder on all pins (why bother with trying to check which ones aren't properly connected? Just re-do them all again) it worked without problems again.

This seemed to be even more common problem on Philips CM8833-II monitor (due to bigger stress on the connector, as video cables usually weigh a lot more)

[_ThEcRoW]

It's called setmport. I use it on one of my A1200 and works like a charm.

[JimS]

One 2000 I ran across had a strange problem with the screws near the joystick port... If I tightened it down, the mouseport would fail. But back it off a quarter turn and it worked. Wierd...

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. ;-)

Here's a picture pointing out where the fuse is:
http://img528.imageshack.us/img528/5816/a2000fusequ3.jpg



The blue things are emi filters. I suppose one could be bad.

-Jim

[dbrads]

JimS, Well flippin ek!

 Didn't look there, yes I have a fuse, I will test it tomorrow.
If it is defective where can I get a replacement (I think I am skilled emogh to replace it myself.

Hellcoder, thanks for the info about swapping mouse ports program, I have downloaded it already! Port Switch by Steve Sloggert.

Thanks for all the replies, good to know there are so many helpful people out there.

[JimS]

In Bahrain, I couldn't tell ya. I'd try some place like Mouser or Digikey. I've heard Maplins mentioned in the UK. Really, any electronics supplier that will ship to you reasonably. If you have to, you could probably get away with attaching an inline fuseholder to the motherboard & using a more standard fuse.

[dbrads]

JimS

 Thanks for the help, I think i will try the inline fuse holder idea, we have a Radio Shack here so I will try there first.

  Keep the faith!