English Amiga Board


Go Back   English Amiga Board > Support > support.Hardware

 
 
Thread Tools
Old 08 September 2005, 12:47   #1
lopos2000
Zone Friend
lopos2000's Avatar
 
Join Date: Apr 2005
Location: Cider is best In The West
Posts: 1,238
Amiga 500 keyboard problem

Hi there,
just tested my A500 and it seems there is a problem with the keyboard.
Some key aren't working at all.
The second row (A to #) isn't working. Numeric keypad isn't working.
Also all Amiga ,Shift, CTRL aren't working. Swap the CIA chips. No different.
Any ideas.
TIA
lopos2000 is offline  
Old 08 September 2005, 14:57   #2
oldpx
 
Posts: n/a
Probably dead. They die like that and I've never heard of any A500 keyboard recovering after this point.
 
Old 08 September 2005, 15:46   #3
BippyM
Global Moderator

BippyM's Avatar
 
Join Date: Nov 2001
Location: Derby, UK
Age: 45
Posts: 9,211
The controller on the keyboard is most likely dead!

This was a common occurance with 500s.. check the caps-lock light.. it usually flashes in a sequence..this will give a clue as to what is wrong!
BippyM is offline  
Old 08 September 2005, 16:06   #4
lopos2000
Zone Friend
lopos2000's Avatar
 
Join Date: Apr 2005
Location: Cider is best In The West
Posts: 1,238
Caps-Lock doesn't work. No light at all.
lopos2000 is offline  
Old 08 September 2005, 17:48   #5
oldpx
 
Posts: n/a
On the bright side, now you have a set of spare keys.
 
Old 08 September 2005, 17:52   #6
lopos2000
Zone Friend
lopos2000's Avatar
 
Join Date: Apr 2005
Location: Cider is best In The West
Posts: 1,238
Looks that way. Cleaned the whole keyboard and all the keys but still no luck. Damn it.
lopos2000 is offline  
Old 09 September 2005, 12:05   #7
BippyM
Global Moderator

BippyM's Avatar
 
Join Date: Nov 2001
Location: Derby, UK
Age: 45
Posts: 9,211
The ribbon might be frayed/damaged.. this was a common accurance too unfortunately
BippyM is offline  
Old 09 September 2005, 12:19   #8
lopos2000
Zone Friend
lopos2000's Avatar
 
Join Date: Apr 2005
Location: Cider is best In The West
Posts: 1,238
I took out the 3.5'' drive and underneath i found some corroded IC's (U34 ,U15, U42) and parts. Must be that. That's what you get if you buy from eBay. I am taking it apart and sell of what is still working. The starnge thing is it still started up alright. Everything was working fine accept the keyboard.
Anyhow, thanks for all the help.
lopos2000 is offline  
Old 09 September 2005, 19:18   #9
Jope
-
Jope's Avatar
 
Join Date: Jul 2003
Location: Helsinki / Finland
Age: 40
Posts: 8,414
Corroded ICs on the motherboard will not affect missing rows / columns on the keyboard.

The keyboard talks to the motherboard via a serial protocol. Either you get keycodes or you don't but it won't receive some and not receive others.

This problem is in your keyboard.

1) the membrane <-> controller board connection is intermittent or broken for some signals
2) the membrane itself has some corroded or short circuited lines
3) there are broken solder joints in the controller board

So.. We'll start with the easiest.

Inspect the solder joints in the controller board. Reheat them with a soldering iron if unsure (perhaps add a small tiny bit of fresh solder to the joints). Test the keyboard.

If it didn't start working, then you need to open up the keyboard itself.

Take out all the small screws, have a small bowl or container next to your workspace where you can put them so you don't lose any.

Remove the black plastic keyboard mechanism.

Take a look at the membrane. Do you see any thin breaks in the silver conductor? Open the connector where the membrane connects to the controller board, are any of the contacts corroded or broken? Has there been a liquid spill? You can try to clean that off with a moist piece of kitchen paper.

You can try to blacken the broken conductors with a soft pencil, but be careful not to make things worse by using a too sharp point. Also silver paint works nicely (the stuff you use to repair car back window defrosters).

Be extra careful if you attempt any repairs in the area that plugs into the connector of the controller board.

If you happen to make things worse, don't worry - there are plenty of A500 keyboards in this world you can buy to replace the one you've got.

Last edited by Jope; 09 September 2005 at 19:26.
Jope is offline  
Old 09 September 2005, 19:31   #10
lopos2000
Zone Friend
lopos2000's Avatar
 
Join Date: Apr 2005
Location: Cider is best In The West
Posts: 1,238
If have cleaned the keyboard with no luck at all. The membrane was a bit sticky so i cleaned it with conatct spray. Cleaned all keys and contact. But still no luck. I will have a look if I find a dry contact on the IC itself.
Thanks for the help
lopos2000 is offline  
Old 18 September 2005, 23:11   #11
Seblington
Amiga Nutter
Seblington's Avatar
 
Join Date: Sep 2005
Location: Paignton, Devon.
Age: 40
Posts: 220
Send a message via AIM to Seblington
I will take a trip into my loft shortly, its where most of my Amiga bits lay, if I come across a keyboard I will give you a shout, it would probably cost about £5 to ship if you want it, unless you already have a spare?
Seblington is offline  
Old 19 September 2005, 00:31   #12
lopos2000
Zone Friend
lopos2000's Avatar
 
Join Date: Apr 2005
Location: Cider is best In The West
Posts: 1,238
@seblington
Thanks for the offer. I got already a spare one.
lopos2000 is offline  
Old 06 October 2005, 14:56   #13
BippyM
Global Moderator

BippyM's Avatar
 
Join Date: Nov 2001
Location: Derby, UK
Age: 45
Posts: 9,211
http://amiga.emugaming.com/selftest.html

Thanks to THB for finding and emugaming for hosting

I'm gonna put this in a post in the Hardware section and make it sticky anyway
BippyM is offline  
 


Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools

Similar Threads
Thread Thread Starter Forum Replies Last Post
Amiga 500 keyboard 5 keys not working Nikolaj_sofus support.Hardware 18 01 June 2020 14:39
Amiga 500 keyboard power Hoopz support.Hardware 4 07 April 2013 06:27
Wanted: Amiga 500 Keyboard nebno6 MarketPlace 1 26 August 2011 23:46
Amiga 500 with Supradrive Keyboard Issues Sargie support.Hardware 3 15 October 2010 03:31
Amiga 500 Plus keyboard problems adgloride support.Hardware 12 07 July 2004 16:48

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT +2. The time now is 23:54.


Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2021, vBulletin Solutions Inc.
Page generated in 0.09045 seconds with 13 queries