VOGONS


First post, by Lylat1an

User metadata
Rank Member
Rank
Member

I have an external SCSI CD changer that I'd like to use as a multidisc holder. (Because it appears as 7 separate drives in operating systems) But it doesn't want to eject the tray without being connected to a SCSI controller.

Is there a way I can make it think it's connected? Like maybe shorting a pair of pins?

It uses HPDB50 connectors if that helps.

Reply 1 of 5, by paradigital

User metadata
Rank Oldbie
Rank
Oldbie

I wonder if simply connecting a terminator would do. Perhaps it’s sensing the open IO lines?

Reply 2 of 5, by Horun

User metadata
Rank l33t++
Rank
l33t++

Maybe but doubt it. Would help to know the make and model of this CD changer. Some SCSI devices required an Initiate handshaking between controller and device (though many SCSI HD's will spin up w/o it or be jumpered to) to "turn on" (am being very simplistic) sort of like a mouse or old modem in the ISA slot that gets power all the time but cannot do anything unless a driver (or in this case a scsi adapter) sends an attention command to the device to be ready to work (again being very simplistic) 🤣

Hate posting a reply and then have to edit it because it made no sense 😁 First computer was an IBM 3270 workstation with CGA monitor. Stuff: https://archive.org/details/@horun

Reply 3 of 5, by BitWrangler

User metadata
Rank l33t++
Rank
l33t++

Hmmm is that default behaviour on SCSI CD-ROMs?? Think I might have left a couple languishing in the junk pile because despite having front panel controls, they wouldn't "do anything" when connected to power and fed an audio CD.

Unicorn herding operations are proceeding, but all the totes of hens teeth and barrels of rocking horse poop give them plenty of hiding spots.

Reply 4 of 5, by Lylat1an

User metadata
Rank Member
Rank
Member
Horun wrote on 2021-12-20, 02:14:

Would help to know the make and model of this CD changer.

NEC MultiSpin 4xc.

Reply 5 of 5, by Horun

User metadata
Rank l33t++
Rank
l33t++
BitWrangler wrote on 2021-12-20, 02:52:

Hmmm is that default behaviour on SCSI CD-ROMs?? Think I might have left a couple languishing in the junk pile because despite having front panel controls, they wouldn't "do anything" when connected to power and fed an audio CD.

Yeah I remember trying to test some and many did not work unless connected...oops forgot all my spares are in storage

Lylat1an wrote on 2021-12-20, 20:51:

NEC MultiSpin 4xc.

Supposedly based on the Nakamichi MBR-7 so will dig around and see what pops up....

added: found two 4x cdrom . Neither has Play buttons just a eject button.
Ok one the tray opens/closes like normal, the other the led just blinks at me 🙁

Hate posting a reply and then have to edit it because it made no sense 😁 First computer was an IBM 3270 workstation with CGA monitor. Stuff: https://archive.org/details/@horun