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SCSI CD Drive 68 pin -> 50 for Macintosh use?

Posted by: MrGasS27 on 2017-05-24 08:19:22 Hi everybody, I bought on eBay a SCSI CD-Rom drive, a Plextor PX-20TSi, on the announcement was written that the drive was used in a server, so, when I unpackaged it I found a 68 Pins SCSI port instead of 50 Pins port, if you search for manual you can found a 50 pins port on the back of drive. I want to use it on my Macs (IIci and Quadra 700) and I want to put it in a SCSI case that converts 50 Pins drive to Centronics (and cable is a Centronic -> DB25) If I install a 68 to 50 Pins (both male) can the CD Drive works on my Macs? Thank you 🙂

Posted by: MrGasS27 on 2017-05-24 08:23:37 P.S: I want to install a 60 -> 50 pins converter, the drive was manufactured in November 1997

Posted by: BadGoldEagle on 2017-05-24 08:33:39 As long as you set the jumpers accordingly (you won't be able to select SCSI IDs on the fly anyway), it "should" work with the 68pin->50pin adapter. SCSI is SCSI after all. Your drive might be SCSI-3 though. It's supposed to be backwards compatible with SCSI-2 so... you should be good.

Posted by: NJRoadfan on 2017-05-24 08:53:33 Must been an OEM deal as the only retail drive Plextor sold with wide SCSI was a 40X drive. Make sure the 68 to 50 pin adapter you have properly terminates the upper byte of the data lines, otherwise it likely will not work. It might not be a problem though as this drive doesn't appear to be a real "wide" SCSI device since it only allows ID setting from 0-7.

Posted by: MrGasS27 on 2017-05-24 09:10:25 Yes, it allows to select SCSI ID from 0 to 7, I think it isn't a wide SCSI device

Posted by: Themk on 2017-05-24 09:10:55 I've used 68-pin HDDs in my macs before. I don't see how a CD-ROM is any different. Make sure your adaptor terminates the high byte though.

Posted by: Unknown_K on 2017-05-24 12:50:48 Get a FWB jackhammer and use 68 pin for all drives! The only issue I could see is termination with 8bit and 16 bit devices on the same cable. Macs tend to terminate the line using the CDROM drive at the end of the cable. I wonder if that CDROM drive is true 16 bit or just an 8 bit drive with a 16 bit connector.

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