Are the drives terminated at the end of the bus? Maybe you need some termpower as well to get the drives going.

Robin4 wrote on 2020-12-09, 03:28:

Are the drives terminated at the end of the bus? Maybe you need some termpower as well to get the drives going.

Both drives have the resistor strips (packs?) in place on their end. They receive power and spin discs (I can see the 1x doing it - the 12x - disc comes out on the tray in different positions, plus I can hear it spin).

The 1520 has the jumper set to be terminated on board for the internal 50 pin connector (IIRC), but I don't have an external terminator out on the back of the card. I do have one somewhere, I'll try that, thanks.

I also have a 1542 SCSI card which I know works in yet another system, I'll give it a go with that.

Perhaps it does not like synchronous transfers.
Try to change it in controller's device settings.

Disruptor wrote on 2020-12-09, 05:13:

Perhaps it does not like synchronous transfers.
Try to change it in controller's device settings.

I wouldn't be sure how to change that on the 8 bit Future Domain card, but IIRC it's in asynchronous mode on the 1520, and at the second-lowest transfer speed. I'll check it again though, thanks for the tips.

Quick update - the Pioneer unit was a dud. I took out a 4x SCSI CDROM from a working machine and it does work in both systems.

Pioneer's laser didn't even turn on when attempting to read discs. I poked around in it a little more, and I made it worse - now the drive won't even spin up. Not surprised, I've not had luck with Pioneer drive lasers in the past.

Ewaste pile.

I still don't know why the 1X doesn't want to work - the laser does articulate and shine - I will try putting in an audio CD and see if it will just play that by itself. I'm not giving up on a caddy loader so quickly 😉

Jed118 wrote on 2021-01-09, 23:32:

Quick update - the Pioneer unit was a dud. I took out a 4x SCSI CDROM from a working machine and it does work in both systems. […]
Show full quote

Quick update - the Pioneer unit was a dud. I took out a 4x SCSI CDROM from a working machine and it does work in both systems.

Pioneer's laser didn't even turn on when attempting to read discs. I poked around in it a little more, and I made it worse - now the drive won't even spin up. Not surprised, I've not had luck with Pioneer drive lasers in the past.

Ewaste pile.

I still don't know why the 1X doesn't want to work - the laser does articulate and shine - I will try putting in an audio CD and see if it will just play that by itself. I'm not giving up on a caddy loader so quickly 😉

I reckon that, either the laser on the 1x is out of phase. you could try and find the pots that adjust it and read up on a tutorial for adjusting faulty lasers in game consoles. I did this with success with a sega saturn about 9 years ago and it's still going strong today.
Or that the laser control board has weakened/worn capacitors, possible since 1x drives were deemed obsolete before 1995.
If not the laser, than the other possible cause of the problem would be a defective IC on the CD-ROMs logic board. some early Toshiba cd-roms had cache memory added to speed up data access and improve buffering and old mem chips can go bad.

Vic Zarratt wrote on 2023-01-05, 12:03:

I reckon that, either the laser on the 1x is out of phase. you could try and find the pots that adjust it and read up on a tutor […]
Show full quote

Jed118 wrote on 2021-01-09, 23:32:

Quick update - the Pioneer unit was a dud. I took out a 4x SCSI CDROM from a working machine and it does work in both systems. […]
Show full quote

Quick update - the Pioneer unit was a dud. I took out a 4x SCSI CDROM from a working machine and it does work in both systems.

Pioneer's laser didn't even turn on when attempting to read discs. I poked around in it a little more, and I made it worse - now the drive won't even spin up. Not surprised, I've not had luck with Pioneer drive lasers in the past.

Ewaste pile.

I still don't know why the 1X doesn't want to work - the laser does articulate and shine - I will try putting in an audio CD and see if it will just play that by itself. I'm not giving up on a caddy loader so quickly 😉

I reckon that, either the laser on the 1x is out of phase. you could try and find the pots that adjust it and read up on a tutorial for adjusting faulty lasers in game consoles. I did this with success with a sega saturn about 9 years ago and it's still going strong today.
Or that the laser control board has weakened/worn capacitors, possible since 1x drives were deemed obsolete before 1995.
If not the laser, than the other possible cause of the problem would be a defective IC on the CD-ROMs logic board. some early Toshiba cd-roms had cache memory added to speed up data access and improve buffering and old mem chips can go bad.

I've heard it may be worn caps. I'll start with that 😉

Vic Zarratt wrote on 2023-01-05, 12:03:

I reckon that, either the laser on the 1x is out of phase. you could try and find the pots that adjust it and read up on a tutorial for adjusting faulty lasers in game consoles. I did this with success with a sega saturn about 9 years ago and it's still going strong today.

I can confirm this, I have had to do this with a couple of original xbox's. It is the laser voltage throughput becoming weaker over time, there is usually a dial you can turn after removing a bit of glue to raise the voltage.