Please help me with my 500 problem

[golem]

Its a weird one but I expect it from hardware this old. When I boot up my 1.3 A500 from cold, very often the caps lock key flashes in a burst of 3 and no key entry is possible. I looked it up in the manual and it is a "watchdog timer test failure" but I don't know what this means and how I can fix it. Occaisionally while it is in this state repeated key entries are registered without actually being pressed like jjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjjnnnnnnnnnnnnnnnnnnnnn. Eventually if I warm reset the machine the flashing caps lock goes away and it works. What do you reckon? Caps? Or try a new keyboard maybe. Will a 1200 keyboard work in a 500?

[actung_bab]

well hi the 1200 keyboard wont be of any use . l say just try give it clean check that all chips are seated . sounds like just the keyboard or the chip that controls it.
the flashing caps lock is to show something not working right.
somone sent me this link for my 2000 that keyboard doesint work at all
http://home.arcor.de/kickstart/TKA/Tutorials/troubleshooter/trouble2.html
but in all truth u most probably better taking to old tv repair guy that can look at for you
other wise you do more damage unless your good at fixing electronics that is

[mechy]

reseat all the 500 chips first(dont just push on them,pull them and re-install them,Pushing on them rarely is a long term fix.

If that doesnt help,try resoldering the keyboard controller chip. i've seen this happen alot on 500's.. no telling how many kbds have been tossed from this problem.

Mike

[ognix]

Yes, after reseating (pull and place again) all the chips inside your A500, if the problem persist, desolder the keyboard controller (on the small PCB attached to the keyboard itself).
It happened to me as well 10 years ago, or so: I changed it.
The easier way is to get another PCB from another (not working) A500.
You need electronics skills, anyway...
By!  

[SaMiga]

Had similar problem years ago, i unplugged the small pcb on the keyboard

I found out that the the black wire Pin 1 and Pin 2 on the pcb was coroded for some reason.
Resoldered it and the problem was fixed.

Can't guarante that it works for you, but it sounds familiar.

I bellieve the colors are standard for A500

Pin-Function-Color
------------------
1   CLOCK-Black
2   DATA-Brown
3   RESET-Red
4   +5V-Orange
5   N/C
6   GND-Green

Cheers
SD-H