Need some advice - A600 blinking caps lock.

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ElectroBlaster

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AmiBayer
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So my Amiga collecting saga continues with me pulling in another A600. Ebay again (I never learn lol)

This one was sold as "Faulty for spares" and detailed as working but cannot boot disks! Basically it has a really nice and clean Panasonic JU which had suffered mouldy disks at some point, the heads were gunked and filthy.

The niggles that plague most A600's are here:

The keyboard membrane is shot! Something has melted tracks off? So its gone for good. A new membrane will sort this easy!

The led board had wires adrift, nothing a good dose of soldering iron wont fix!

The board is a Rev.2D but with an older rom that does not support ide? I am confused as to why this rom on a 2D but then again, I suspect the better one was robbed and the older one was dropped in.

The board works quite well and the overall condition of things is clean! All capacitor pads are shiney, some caps are domed though.

With everything hooked, it starts up and boots fine but I am getting a constant "Blink blink blink blink blink" on the caps lock. Could this be the bad keyboard membrane?

Reading up about caps lock codes it states "Keyboard rom checksum failed" :mad:

Any idea's?
 
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seems like the Keyboard is a weak link in the A600 my keyboard had a row of keys not working, problem was burned tracks from the keyboard chip to the mobo connector,get your multimeter out and check continuity from the chip to the mobo k/b connector bet there are some tracks gone also here.
 
Ok I will crack on and have a good nose around.

From what I can suss out:

I have tried two other different keyboards, one better than the other!

From a cold boot, the amiga will happily sit ticking away to itself, I can do the nerve-pinch reset for ever if I wanted to, it just plods on fine with no "blinking" caps lock led. This is on both keyboards.

Soon as I flick the power switch on the psu then things change! Power back up and the caps lock sits solid for a bit then it starts the "blink blink blink blink blink" thing again? This is with both keyboards again.

I will now strip the entire thing down, remove the rf sheilding and have a good nose!

The original keyboard does infact have melted tracks in the ribbon and I am also sure it will be worse when I strip it down into parts.

What the hell could have caused this? Is this what happens when capacitors go bad and when a psu goes awol?
 
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i dont think bad caps will melt the ribbon,i still beleive the controller has gone bad or traces leading to it are bad or someone has tinkered with it somehow.
 
Just a few days ago I had a similar issue when I was testing some Kickstart ROMs.

I noticed that, leaving the keyboard plugged with the membrane cable a little bit bent, with 2 different 37.300 ROMs I had the Caps-lock key blinking but with a 37.350 ROM it didn't blink (except the standard blink when turning on the power).

Then, when I put the membrane straight and the keyboard in place, I didn't have this issue anymore, even with the 37.300 ROMs...

I don't know why this happened, however you could try with a different ROM (if you have one) since that is a very easy test to do...
 
I have more roms, just have not tried them yet!

all old membranes I have are suspect. Each of them has a problem of some kind. I do have a brand new one but I really do not want to mess with it until I have a perfect 100% good board.

The rom chips I have are:

37.300
37.350

shall try and have a crack tonight, the best option for me is to pull the board out fully and get a magnifying glass and multimeter on it.
 
Hi...
i know that this thread is somekind of old..
but today i noticed one thing while i was upgrading my psu to a Meanwhell RT-50b. and this only hapened with my A600. while i was experiment, the new psu, i noticed that the Capslook was blinking. i switched to my ol A500 psu, and no blinkings, swapped again, and the blinking started, i measured the Meanwhell voltage, and it was at 5,65v i´ve ajusted to 5,05v and the blinking stopped. but the sound is steady, but VERY low.... if i use the A500 PSU... the volume is normal... but with cracks...
 
I have stumbled on this post as currently I am facing with the same issue... From cold boot the LED does not flash...but when resetting in few minutes caps lock LED starts to flash, and occasionally a guru is prompted on the screen....

Keyboard membrane is not to blame as it is bought brand new... Today I try and swap the PSU, currently am using the A500 PSU with 4.3A on 5V rail. This PSU has been also measured and reports correct voltages [unloaded]... Then if issue persists, will try and swap KS ROMS.
 
Update: Issue seems intermittent... Sometimes if I close the case the caps lock issue vanishes automatically?! I am sure that they metal part of the keyboard is not touching anything below, as I put a large ESD bag.... What I have noticed is that sometimes, when the caps lock LED does not flash, is that for instance, keys F7 and below row of keys don't work... Then re-opened, re-attached keyboard ribbon where this time F8 and below keys do not work.... After many retries I got all keys working.... Then again today I re-opened the case to install the floppy drive, since the client had a modified Samsung PC drive... and again the caps lock flash issue is present.... Seems the membrane does not like to be removed... Again to remind you that the keyboard membrane is brand new.. And also used a known working PSU....
 
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