Help with SCSI

[tweedy]

I have a SPARCstation IPC that has recently received a new power supply thanks to the work of a kind soul.

The system boots and runs using its ancient and tiny spinning hard drive, a Maxtor LXT213SY.

The weird thing is, the system will not accept any other SCSI drive.

• Without the drive attached, the system hangs on startup after the framebuffer wakes up but before completing any tests; Stop-A doesn't do anything
  • Connecting any other drive, real or emulated, SCSI2SD or BlueSCSI or ZuluSCSI, has the same effect
• The system tolerates me changing the SCSI ID and attaching it via either the internal or external SCSI ports
• Adding a SCSI drive to the bus has no effect; the system boots but no other device is recognized

The NVRAM chip has been replaced and all the values reset, so I don't think that's the culprit.

But for the life of me, I can't even venture a guess as to why the system insists on only this one drive. Could it be something wrong with the SCSI chip? (But then why is it happy when the SCSI ID is different, or when I reconnect the blessed drive via the external SCSI port?) Does the MAXTOR drive have some archaic feature that none of my other spinning disks or emulators have?

I'm truly at a loss, so any ideas much appreciated.

 

[Melkhior]

Could be termination. Check the specifications of the drive to see if it has built-in termination and if it's jumpered enabled (on-disk termination is usually optional).

However, inadequate termination shouldn't prevent the system from booting with nothing attached...

I think you need to figure out why it doesn't reach the openboot prompt with no drive, because that is the weirdest part IMHO. Maybe try adding/removing termination on the internal and/or external port to see if the diskless status improves?

 

[ScutBoy]

Agreed - termination seems to be the culprit, and the fact that it hangs at the OpenBoot prompt _is_ weird.

Might check to see if/how TERM POWER is set on the drive, and make sure that's set the same with any other drive. Note that not all drives supply TERM POWER, so you might need to get it from somewhere else on the bus.

As far as no other devices being seen on the bus even with the working drive, that's weird as well.

I can't remember if the IPC has a fuse on the SCSI interface. That might be worth checking as well...

Interested to hear how this one turns out!