A500 Boot Problem

[BGary335]

I recently purchased an A500 off of EBay. Upon powering it up, I get no lights other than the Caps Lock key, which stays lit continuously, and no video (I'm using an A520 adapter, by the way). However, I can tell a video signal is going to the TV when I switch the computer on, there's just nothing on the screen. I try inserting a floppy, and get nothing from the computer, except a momentary spin of the floppy drive. I tried replacing both the Agnus chip and the Kickstart ROM (in fact, I've tried several of each)but nothing changes. I've noticed that neither the CPU chip nor the Kickstart ROM get even a little warm. The rest of the chips however seem to heat up at least a little.

Any ideas on what the problem might be? I'm thinking maybe its the CPU, butI'm not sure. Any help wouldbe very much appreciated!

[BGary335]

Any ideas at all?

[Tomas]

tried another psu?

[zipper]

A firm push to every socketed chip - or remove and reseat, that's the first thing to do.

[Speelgoedmannetje]

zipper wrote:
A firm push to every socketed chip - or remove and reseat, that's the first thing to do.

Also, connectors can get a bit rusty, so try to make it clean (I always use a tip of a towel wich is a very tiny bit wet). And also make sure you give the floppy cable a push too.

[BGary335]

Yes I have tried another PSU, and it made no difference.

Yes I ahve inspected all the chips and connectors, cleaned them, and made sure they were seated properly.

[Amiga4k]

Un-lock the CapsLock key, and report back. Everything reverts back to an Agnus problem, but you need to un-lock that key first to know anything else.

Is the 68000 hot?

[ajlwalker]

@ Amiga4k

I'm sure he means that when he switches on the caps lock light comes on and stays solid.  He isn't pushing the caps lock key.

From memory this is a fault indicator on Amigas, but I have no idea what it means.

I seem to recall it was something to do with the CIA chips but I don't really know.  Anyone?

[BGary335]

@ ajlwalker:

You are correct. I am not pressing it, rather when I switch the system on, it comes on and stays on for about 5 minutes, then goes off. Just seems to me to be longer than it should be. Granted, I haven't used a 500 in 5 or 6 years, but from whatI can remember the Caps Lock light never stayed on that long on boot up.

[BGary335]

Well the problem seems to have worsened. All I get when I power up now is a continuous Cpas lock light and nothing else.

[Argus]

Did you try swapping the CIA chips and see if it works then?

[DrDekker]

Try booting up with the keyboard disconnected - it could be a faulty chip on the keyboard.  Can't remember off hand what it's called, but you'll find it adjacent to the LED's.  Usually a faulty keyboard chip will generate a flashing sequence through the caps lock LED and prevents the Amiga from booting up.  This kind of problem seemed to affect A500+'s more than A500's.  From what I remember, the chip is soldered directly to an A500+ KB and socketed on an A500.

[HellCoder]

Did you talk to the sellar about this ?

[BGary335]

@Argus

What are the CIA chips? Sorry but I'm not too familiar with anything other than the Kickstart ROM chip, the CPU, and the Agnus.

@HellCoder

Yes but it was sold as is, and all he'll give me is the same one-liner:Sorry it was sold as is. Not even an attempt at helping. It's that attitude that leads me to believe he was just trying to rip someone off. Yes, the auction did say as-is, but when you give a real nice description of the computer, and include none of the bad stuff, its hard to not buy it. If he would've given some reason for why it was being sold as is (like maybe that it doesn't power up), than I wouldn't have bought it. Unfortunatately, I had to make a decision based on what info he did give, and as you can tell I made the wrong decision.

@DrDekker

I've tried disconnecting the keyboard, but it doesn't seem to have made any difference.

[McVenco]

What are the CIA chips? Sorry but I'm not too familiar with anything other than the Kickstart ROM chip, the CPU, and the Agnus.

They are the 2 chips on the mainboard marked "EVEN CIA" and "ODD CIA". They are quite often the cause of numerous problems.