A500 failing?

[hotdiggity]

Well, tonight I pulled the ol' Amiga 500 out of the closet. It's been a few years since I powered it on. Unfortunately, it appears that the internal disk drive is failing -- it will start to read, like it recognizes that a floppy has been inserted, but then it stops after a few short noises. The insert-floppy screen goes away, then comes back after a bit. This happens with pretty much any floppy. Occasionally it will get to a flashing red and black screen that says software failure.

I'm also getting weird graphical glitches/artifacts on my screen (see attached). This happens both through the B&W RCA output and color video out via my A520 adapter. I don't have an actual monitor anymore.

Does anyone know what's going on?

[Harrison]

I could be wrong, but I don't think it is your floppy disk drive that is the problem, but instead a fault on the A500's motherboard.

What are the errors you get with the guru software error screens (the black/red flashing screens)? These error codes can often help work out what the problem is.

One of the others here who knows more about the actual Amiga hardware than me will be able to give you a better answer, but with the graphical corruption on screen, floppy drive not working, guru message screens etc it could be faulty ram, a faulty custom or CIA chip, or something else...

Best to wait for Zetr0 to log into the forum. He should be able to help further.

Oh, and welcome to classicamiga :thumbs:

[hotdiggity]

Your mention of faulty RAM led me to try something. I pulled the extra RAM chip out of the bottom and tried booting it up. All I got was solid colored screens and nothing else. It wouldn't boot from a floppy.

I put the RAM back in and I got similar color screens (I think it was dark grey, grey, then white), then for a brief second a black background with garbled red text (it didn't stick around this time, it flashed away after a second).

So then I pulled the A520 off and plugged in via B&W again. I got a readable error message: Software Failure. Press left mouse button to continue. Guru Meditation #00000003.00C01570. I pressed the left mouse button and surprisingly, it booted off of the Workbench disk. I shut it off, plugged the A520 back in, powered it on, and it booted to Workbench again, in color. I don't know what happened, but it's working now. I kind of wonder if it will remain that way, though.

Ahh well, time to play some Firepower!

P.S. I looked up the error code at this site (http://www.scotek.demon.co.uk/guru.html) and apparently the 3 means Address Error. My question is: what does Address Error mean? ;)

[Harrison]

Some guru errors are quite cryptic and hard to work out what they mean. Address Error probably means a ram issue, but I could be wrong.

It is good news that you finally got it to work. Maybe the trapdoor ram expansion wasn't seated correctly and you removing it and the putting it back in solved the problem. Long shot and a complete guess.

Other common problems like that are if the Amiga is stored in the attic and has got damp or condensation in it. So when you put it back into a warm room it won't work until it has adjusted to the atmosphere of the room.

[Demon Cleaner]

Maybe the trapdoor ram expansion wasn't seated correctly and you removing it and the putting it back in solved the problem.Yeah, or the contacts themselves were a bit dusty and by removing/replacing them, they have better contact now. You can still try and clean the contacts and use contact spray on them.

[Fern]

Hmm, this thread has got me thinking... aside from the corrupted screen this behaviour was very similar to that of my A1200 which is currently in a million pieces awaiting repair.

If I have a motherboard fault as well I am going to be all kinds of angry! :mad: I suppose I shall see what happens with a new FDD.

[Harrison]

With the A600 and A1200, if the floppy drive stops working it normally is the floppy drive that needs replacing. This wasn't the case with the A500 because the older hardware was a bit more fragile in design and many things can fail.

[Demon Cleaner]

Didn't Rod Stewart have a song called "I am failing"? But that wasn't about Amiga I think :hmmm:

[Harrison]

No, that was just about his voice!

[taunusanden]

I have seen corroded batteries on A500 ram expansions, causing failures.
Thoose damn batteries kill a lot of our dear Amiga's :(

[Harrison]

Indeed they do. Also the A500 Plus has one of those evil batteries on its motherboard. I really must open my one up at some point and check the battery.

I've already removed the one from my A4000. It was starting to fur up around the ends and its legs so it was removed before it had chance to start eating at the motherboard.

[Fern]

It's also a common problem with a lot of old 80s synthesizers.. what we tend to do there, is solder some flyleads to the motherboard and mount a lithium button cell on a holder elsewhere in the casing. NiCd Batteries cause all manner of problems when they get old and leak!

[hotdiggity]

Unfortunately the saga continues. I think Harrison might have been right about the motherboard because the symptoms came back this evening.

I was transferring some ADFs to floppy via transdisk/ADF Sender Terminal with a serial cable & null modem. Things looked good, the first disk transferred in ~8 minutes (about normal based on past experience), but then the next disk took a whopping hour and 45 minutes! That's when I started to suspect something was up.

I tried booting from the new disks and they didn't work; I tried looking at them in Workbench and I was told they were bad. I did another and it took 43 minutes and then I noticed some graphical artifacts on the screen. I moved some windows around and the artifacts took over. See attached #1.

For kicks I pulled the RAM expansion out and put it back in. I flipped the power off and then back on. The first time it just stayed at a blank white screen. The second time it presented me with the insert disk screen with artifacts (attached #2 - note that the weird bendy swirly lines are actually from my TV screen). It won't recognize any disks.

Any other ideas or things for me to check? Should I rip it apart and look for a leaking battery? Is she a goner?

[Harrison]

What does the system do without the extra ram fitted?

The next step would be to take the A500's case apart and look over the motherboard for any signs of damage. Blown capacitors (the tops would be bulging up slightly rather than flat), and also make sure all of the socketed chips in the system are well seated in their spckets by giving them all a gentle push into their sockets.

[Buleste]

At the moment I would try cleaning all contacts on the Mobo with Isopropyl alcohol (especially the RAM expansion) and give the Mobo a good inspection to see if there's any visible issues.

[woody.cool]

Indeed they do. Also the A500 Plus has one of those evil batteries on its motherboard. I really must open my one up at some point and check the battery.
I had one of those evil batteries completely wreck my beloved A500 Plus!
If I remember correctly, I posted pics of it when it happened.

[hotdiggity]

What does the system do without the extra ram fitted?

Last night it wouldn't get past a blank white screen without the RAM. I tried it again this morning and it actually booted from my Workbench disk. It did complain about not having a clock backup battery or something. I will inspect the motherboard after work today.

[woody.cool]

What does the system do without the extra ram fitted?

Last night it wouldn't get past a blank white screen without the RAM. I tried it again this morning and it actually booted from my Workbench disk. It did complain about not having a clock backup battery or something. I will inspect the motherboard after work today.
The reason for the error about the lack of battery is because you have the Setclock LOAD command in your Startup-Sequence.

[hotdiggity]

I ripped apart the A500 and inspected the motherboard. No leaking capacitors, no discolored parts on the board. I pushed down on all of the chips just to be sure they were seated snugly. Since I put everything back together I haven't had a problem, but I wouldn't be surprised if it's just playing games with me. Yeesh. ;)

[woody.cool]

I ripped apart the A500 and inspected the motherboard. No leaking capacitors, no discolored parts on the board. I pushed down on all of the chips just to be sure they were seated snugly. Since I put everything back together I haven't had a problem, but I wouldn't be surprised if it's just playing games with me. Yeesh. ;)
You may have inadvertantly reseated something!
If it still persists, I reckon you'll have to get ther soldering iron out (or you could take the lazy option and get an A500 mobo off ebay)

[Buleste]

Glad everything's worked out for you.