steve@icad.com (Stephen Carr) (04/21/89)
I have recently experienced extended problems with the Exabyte tape drive. We have attached the Exabyte drive to a Sun3/260 with a SCSI-2 (sc) host adapter. We are running SunOS 4.0.1 and after completing installation of the drive, we were unable to access it. The host adapter would return an I/O error and the device controller would return a mode select failed error. After going through all the standard checks (4.0.1 SCSI patches removed, replaced X60 backplane adaptor, etc.) we suggested to Exabyte that they might have a problem with their device driver. Exabyte responded by examining their device driver software and suggested that we may have a PROM on the tape drive initialized improperly. They described to us the proper sequence for resetting this PROM and (at long last) we have a functional Exabyte tape drive. This PROM can be reset by running adb on /vmunix and querying the variable st_ex_MX4_23. After saving a copy of the working kernel, the command sequence is adb -w /vmunix st_ex_MX4_23?W 0 The query should return 0x1 and then reset to 0x0. I'm indebted to both Michael Couch and Bob Wagner of Perfect Byte, Inc., for all their help. Steve Carr @ Icad