Mouse problem on A500

[fiat1100d]

Hello,

on my A500 the mouse has some problems with moving the pointer to the right: other directions (top, bottom, left) work fine, only the right gives problems. The can move but VERY slowly, or it won't move at all. Of course the mouse is working fine on other Amiga computers.

What the problem could be? Some IC needs to be replaced?
Thanks!

[meega]

Is this the same A500 that you mentioned in your other thread - the one you fried something in?

[fiat1100d]

Yes it is, but I actually had the mouse problem since before I fried the keyboard IC. On the motherboard nothing got fried, fortunately, when that happened.

[DrDekker]

If it's a ball mouse - check the side mounted roller for fluff and crud.  The roller is usually lightly sprung and can often work normally in one direction and not in the other direction.

[fiat1100d]

I wrote the mouse works fine on other Amiga computers, so I am thinking about an hardware fault inside the A500 unit.
What chip controls the mouse?

[keropi]

CIA's control the mouse...

[DrDekker]

fiat1100d wrote:
I wrote the mouse works fine on other Amiga computers..

Oops - so you did! :oops:

[fiat1100d]

keropi wrote:
CIA's control the mouse...

Will try swapping them then, thank you!

AFTER SWAP: same problem, so I don't think it's a CIA problem  :-(

[fiat1100d]

Had a look at the schematics and did some more chip swapping... I found it was a partially bad Denise, after replacing it with another unit the cursor movement problem is gone.

Now I have that Denise which is good at video but bad for that mouse issue :-( Would be nice if there is a circuit for replacing that function, but unfortunately I don't think there is one :-(