Erratic Keyboard Behavior (randomly)

[andresv]

Hi guys, since a few days now I'm suffering from a failure in my STE.
The keyboard starts acting funny, pressing keys won't work or generate the wrong character.
This happens more or less randomly, sometimes the machine boots OK and sometimes the machine boots and the keyboard starts misbehaving.

Any ideas?

Agv

[exxos]

Clean keyboard header on the motherboard with IPA ?

[rubber_jonnie]

Perhaps remove the KBD microcontroller if it's in a socket and spray with contact cleaner and re-insert. Check the wires have not frayed where they connect to the keyboard PCB and they have continuity to the connector, and check the soldering on the mainboard connector.

Continuity check all the traces between the connector on the mainboard and the 6850 (U21 I think).

It is possible that the KBD PCB is cracked, so you may need to disassemble and check for that or bad solder joints, but watch out for the rubber domes.

[andresv]

I was about to start removing the case screws (again) on my Atari STE but remembered that a few days ago I dropped my STM1 mouse on the floor and started to behave strangely. Apparently the left button micro-switch got smashed by the drop and not it "gets stuck".

So it seems that this is what was causing the keyboard to behave the way it did... don´t really know what that might have to do, but it is.

When I remove the faulty mouse the keyboard functions perfectly, so mystery solved.



Thanks!



Agv

[rubber_jonnie]

I was about to start removing the case screws (again) on my Atari STE but remembered that a few days ago I dropped my STM1 mouse on the floor and started to behave strangely. Apparently the left button micro-switch got smashed by the drop and not it "gets stuck".

So it seems that this is what was causing the keyboard to behave the way it did... don´t really know what that might have to do, but it is.

When I remove the faulty mouse the keyboard functions perfectly, so mystery solved.



Thanks!



Agv

Ahh, good stuff :)