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[sbeehre]

Hi Everyone

I recently aquired my mates old A500 and after checking it to see if it still worked i noticed some of the keys dont work. I checked the motherboard and on the keyboard header pins the third one from the right apears to have been snapped off... what i want to know is if its supposed to be like that! if not i guess i can by another header pin from the local electronics store and try de soldering the old one and putting a new one in. I checked some of the hi res scans of my models motherboard (rev 6a) but its still not clear wether than pin is there or not! Hopefully one of you guys should be able to help

Simon

[LoadWB]

I'm going to jump too quickly and say that's the "key" pin.

As the keyboard communicates with the motherboard via serial data, if some keys are not working the problem most probably lies within the keyboard.

If you have the stomach for it, you can disassemble the keyboard and clean all of the contacts on the circuit board. What to use varies based upon who you ask, but I like either alcohol and a Q-Tip or good electronics cleaning fluid. Some people swear by rubber pencil erasers. YMMV.

Also clean the rubber on the bottom of the key pegs. This requires a gentle touch.

While you have it apart, look for not-so-obvious breaks in wiring and traces.

I believe you can look up keyboard scan information which would help you determine if entire row/column lines are bad. I believe this is tested by the on-board controller, but again, I'm just making a quick jump.

In my experience, rebuilding the keyboard fixed my problems nine of 10 times in which the keyboard "sort-of" worked, and lacked the flashing CAPS LOCK Light of Death ;-)

[Zac67]

LoadWB is right: if the keyboard works at all, the cable connection is AOK; the problem must be a bad contact in the keyboard matrix.

Do NOT use a rubber eraser on any contacts! They might work for a while, but probably won't last for very long.

[sbeehre]

thanks guys! i already cleaned the top side of the keyboard by taking all the keys off and washing them, and it looks alot better! Could i use isoproply alcohol and the cotton buds you get for the bathroom to clean the bottom?

[sbeehre]

Well i cleaned the kb as you guys suggested and its still not working... anyone in NZ got a working A500 keyboard?

[amigaksi]

I also had a non-working A500 keyboard (and mouse) and this was one of the reasons I started making the simulation program and the cable (which is on auction):

http://cm.ebay.com/cm/ck/1065-29296-2357-0?uid=10022145&site=0&ver=LCA080805&item=320067784 515&lk=ItemDescriptionANDimage

I do have a couple of A500 keyboards which I bought from Ebay for testing and comparing purposes. If you want you can have it for the price of shipping. A couple of keycaps may be missing, but the keys work. You can use the keycaps from your current keyboard if they happen to be similar. Or else, go for the simulator-- it will allow you to simulate your mouse and joystick as well (if you prefer) or have them both shipped together.

[orange]

if you wish PC keyboard adapter, check this out (ATkeyboard).
I've made several of them and they are very good.

[eidofoor]

Oh dear, I have heaps of Amiga spare parts, including several A500 keyboards!! But I'm afraid that I'm a long way from you!

Shipping costs would be a wee bit high..

[Tomas]

I think there should be a missing pin from what i recall from my a500s. I think it is more likely the flat cable thing on the keyboard itself or some shortcut/bad contact on the board. So i would first try cleaning out the electronic board/chips on the keyboard and then check that flat cable. Be very careful about that cable though, as you can easily scrape of the graphite on it.