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Mac SE: internal HDD SCSI termination while also using external SCSI devices
Posted by: Gregory K on 2015-08-27 14:27:55
Dear forum members,

According to SCSI requirements, the first and the last devices in a SCSI chain should be terminated. Since I have Iomega ZIP drive connected to the external SCSI port, there are 3 SCSI devices in a chain:

1. Macintosh SE FDHD itself - SCSI controller on the motherboard (SCSI ID 7)

2. Internal HDD (SCSI ID 0)

3. External Iomega ZIP drive (SCSI ID 5)

The last device on the SCSI chain is the external ZIP drive, so it must be terminated. But what is the "first" device: SCSI controller on the motherboard, or internal HDD?

In other words, do I have to disable termination on the internal HDD when also using an external SCSI device (assuming that SCSI controller is the first SCSI device, and HDD is the second device)?

Posted by: tanuki65 on 2015-08-27 14:33:28
No. 

Posted by: Gregory K on 2015-08-30 08:45:17
Thank you for your reply!

Are there any circumstances in which the Internal HDD termination should be disabled (on Macintosh SE FDHD)?

Posted by: bibilit on 2015-08-30 10:33:15
No, really.

Posted by: Gregory K on 2015-08-31 14:19:44
Great, thank you for your answers!

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