On Sun, Jan 2, 2022 at 9:22 AM Rob Jarratt via cctalk <[email protected]> wrote: > > Hmm... There was already a terminator installed. I tried to remove it in > case there was some kind of double termination, but that didn't seem to > resolve it. The terminator is good because the machine works with other > disks.
If other disks work when they are swapped in without making any other changes, it is probably not a termination issue. However, you still might want to double check that the DSSI bus is properly terminated at both ends. If the M7769 KFQSA is attached to a bulkhead connector panel, there are two versions, one with a single DSSI connector, and one with two DSSI connectors. If the bulkhead connector panel has a single DSSI connector, there should be SIP terminators installed on the M7769 KFQSA next to the DSSI connector on the M7769 KFQSA as one end of the DSSI bus. If the bulkhead connector panel has two DSSI connectors, the SIP terminators should be removed on the M7769 KFQSA next to the DSSI connector on the M7769 KFQSA, and there should be an external terminator on one of the two DSSI connectors on the bulkhead connector panel. If there is no bulkhead connector panel connected directly to the M7769 KFQSA, and instead it is connected to an internal DSSI bus cable inside the chassis, and the M7769 KFQSA is at the end of the internal DSSI bus cable, there should be SIP terminators installed on the M7769 KFQSA next to the DSSI connector on the M7769 KFQSA as one end of the DSSI bus. I would expect the other end of the internal DSSI bus cable to connect to a bulkhead connector panel, which should have an external terminator attached as the other end of the DSSI bus.
