A4000 problem: IDE = good, ATAPI = bad?

[spirantho]

Hi everybody,

I'm trying to repair an A4000. It's working more or less nicely now, except....

The IDE bus is acting very strange.
With an HDD (120MB) on master, it's fine.
With a CF (256MB) on master, it's fine.
With HDD (Master) and CF (Slave) it's fine.

However... put any ATAPI device on the bus....
Put a CD-ROM (Slave) on with the CF and the CF gives lots of read errors. The CD-ROM is not detected.
Put a ZIP250 (Slave) and the A4000 gives a red screen instead of booting. I had it booting once or twice - it never appeared on HDToolBox though.
I have one CD-ROM which is detected by the IDEFIX97 program (the other three I tried don't appear). The name string is garbage. The device always gives no disk present. Eject CD command does work though.

The A4000 is running OS3.9 at the moment. I've also tried with IDEFIX97. FindDevice program gives a recoverable alert of 0BADC0DE.

Does anyone know why this might be happening? Why my CF Card and HDD work, but anything at all ATAPI just blows everything up.

Thanks for any help!

[spirantho]

Yes, and the HDD wouldn't work if that was the problem...
It's a real puzzler!

[spirantho]

It's not the cable, unfortunately. Tried three cables. The same happens.
Doesn't matter where on the cable it is, master or slave - no ATAPI device works - Zip, CDRW, CDROM.. they just don't appear. Also, the Amiga takes 30 seconds or whatever to boot, as if nothing is on the bus.  If there's a CF Card, IDE or nothing on the bus... same thing, ATAPI devices just don't get seen. Even a Zip disk with a valid RDB doesn't get seen.

Really puzzled...

[spirantho]

Yes, it has a DOSdriver. It's just not detecting it at all, though - it's not finding the ATAPI devices on a IDE device scan.

After looking at it some more I've decided to leave it until I can get another A4000 in (no way I want to risk my own precious A4000!). I reckon it must be either Fat Gary or one of the support logic chips, maybe the PLA thingies too.

Very weird how it works ok with an IDE hard disk though. In the meantime the customer whose A4000 it is is borrowing my Oktagon 2008, thereby bypassing the problem.

If/When I finally find out what's been causing this I'll post again in case it helps other people.

Thanks for the help though!

[spirantho]

I tried with OS3.9 and IDEFix 97...

The problem is that the drivers can't even detect the drive. The IDEFix program FindDevice finds only one CD-ROM drive, and on that one the ID string is all corrupt. That's the one that mounts ok and can eject, but that's all. FindDevice in fact usually gives a recoverable error with the code 0x0BADCODE (which means an invalid code has been passed to the controller, I believe)/

So it's definitely not a driver issue, because the same set-up on my A4000 detects the CD just fine.

It's just really confusing that it boots ok off the old 120MB HDD and a 256MB CF Card, but no ATAPI devices at all. If I connect a Zip drive (ATAPI) I just get a red screen. If I boot OS 3.9 with just the CF card, it'll hang when it reboots from Setpatch - with a non-working CD-ROM drive as slave, it boots fine (but can give errors). It's just really odd.

As soon as I get another 4000 to play with I'm determined to track this one down, though!

[spirantho]

Not the PSU unfortunately. I checked voltages which are ok, and that would be unpredicable, where as the symptoms I can see are consistent. Also I checked with just the A4000 and ATAPI drive and there was no change.
Thanks for the idea though!