Just killed an Amiga 2000 keyboard

Hi everyone. I need moral support, i've just fried an A2000 keyboard :(
The facts:
I had an A2000 without keyboard. I had a keyboard whose some barbarian cut the cable. Perfect - let's rebuild a cable!

Well, first problem: after a bit of googling i came out with at least three different pinouts. Moreover, apparently noone on the interwebs felt the need to write the pinout of the internal connector of the keyboard (the one from which the cable starts).
Then, I found this iff on aminet:

http://img18.imageshack.us/img18/6062/a2k2cttvkbd.png

Perfect! The pinout of the connector AND the matching internal cable colours: so, I used the small piece of cable still attached to the keyboard, soldered in a new cable and a matching connector, and checked everything with a multimeter.
Now, let's test it: connect to the amiga, turn on... hmm, no leds on the keyboard... wait, WHAT IS THIS SMELL?
Result: burning smell from the keyboard circuit - even if there's no sign of burning on the pcb - and the fear of having damaged the amiga motherboad, too :(
And I don't even know what's wrong with the cable... *sigh*

Cheers,
Gabriele

What's the provenance of the keyboard? It's possible that the cable was cut off by the previous owner precisely because it was damaged.

Your A2000 should power on just fine without a keyboard, so you should at least be able to check that it's OK.

And, my usual advice to anyone clamouring for technical support: Hi-res photos of the broken thing(s)! That way, our resident techs can see what they're dealing with and advise appropriately.

Good luck, I'm sure there's sufficient Awesome here on the 'bay to get you back up and running!

:thumbsup:

@Gabriele

I am sorry to read the possible loss of the keyboard. Unfortunately its likely you have killed the onboard keyboard serial converter

Here is a pinout I made for you -
http://s4.postimage.org/erxpwmfcn/Amiga5_PD_KI.png

Its very likely you have sent +5v up the CLK line... this will damage the chip... but all is not lost, you can use the chip from an A500 or A500+

You can find these on ebay.co.uk from time to time... infact you could ask eBay member Airey36 if he has any.

I hope that helps

@Andy: Thanks :) I forgot to mention - I already checked, the 2000 turns on just right, I just hope that the circuirty that manages the kbd it's ok.
You're right, I'm going to post a couple of hires photos.
By the way, yes - the level of awesomeness, here, feels pretty high :)

@Zetr0: Thank you so much. You confirmed my thoughts - the pinout on that iff was plain wrong. Do you happen to know if the wire color -> signal association is right, at least?

Cheers,
Gabriele

@Gabriele

Amiga 5pin DIN keyboards were made by many differnt manufactures so colour-codes were not followed... the same with PSU Plug Packs...

while some will be similar, it can not be said for all!

If you have a multi-meter you can buzz-out the pins using the continuity mode...

from this you could map the internal keyboard... +5v / Ground... Data and CLK might be tricky, but it wont kill the keyboard if they are the wrong way arround... you just get a lot of asci "y" character...

Open up your keyboard and take some pics, from here I am sure we could help you more =)

Ok, you asked for it... here are the dirty (well, actually more smelly than dirty) pics :P

Component side:
http://img585.imageshack.us/img585/5...ponent1.th.jpg

http://img577.imageshack.us/img577/3...ponent2.th.jpg


PCB side:
http://img202.imageshack.us/img202/306/pcb1t.th.jpg

http://img825.imageshack.us/img825/9494/pcb2k.th.jpg


@Zetr0:
You're right, i'll check the continuity from the 74xx Vcc and GND pins - so at least I can try to power up the keyboard.

Thanks again for your help.

Cheers,
Gabriele

Hmmm I dont see any visual damage, which is good...

I suspect that the 3Mhz Resonator will need replacing, if you are lucky the Keyboard MPU chip (CSG 6570-036) may of taken the punishment.

In a worse case scenario, everthing is replaceable... the Keyboard MPU can be salvaged from an A500, the logic is cents a chip, and the discretes (diodes / resistors) are less than that...

Strangely enough the hardest to source will be the 3Mhz Resonator... but even then its not expensive.

Quote:

---

Originally Posted by Zetr0

Hmmm I dont see any visual damage, which is good...

I suspect that the 3Mhz Resonator will need replacing, if you are lucky the Keyboard MPU chip (CSG 6570-036) may of taken the punishment.

In a worse case scenario, everthing is replaceable... the Keyboard MPU can be salvaged from an A500, the logic is cents a chip, and the discretes (diodes / resistors) are less than that...

Strangely enough the hardest to source will be the 3Mhz Resonator... but even then its not expensive.

---

Well, I've done some further investigation.
The good news is that, if I give +5v to the keyboard, it powers up, turns on briefly the caps lock led, and then said led works as it should (first keypress on, second keypress off).

The bad news... I took apart the amiga:
http://img33.imageshack.us/img33/449...4231803.th.jpg

Apparently (reading from here) that's the resistor that feeds +5v to the keyboard. In fact, if i check the output on the keyboard socket with a multimeter, it's actually giving out about +4,3v (and if i put a charge, goes instantly to zero).
Tonight I'll try to replace the resistor, hoping that's the only damage -_-'

I'll keep you in touch :)

Cheers,
Gabriele

how you get on with this
am really intressed in converting A500 keyboard to 5 pin din for A2000/a4000

@algasystems

I wonder if I could trouble you to pop off a keycap from a normal key. Not any long keys like spacebar, just a reglar key like F1 or ESC. I need to know what kind of switches are in your A2000 keyboard and the serial number.

I am hardcore studying the keyboard industry for the last 60 days and the switches in old A2000 keyboards are legendary. But supposedly different keyboards used different switches. So I am trying to sort out the mystery.

Thanx.