CDU-710/M disk controller

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The CDU-710/M is a UNIBUS SCSI disk controller made by CMD Technology Inc.. It fits in a quad Small Peripheral Controller slot. It support's DEC's Mass Storage Control Protocol.

4.3BSD Quasijarus bootstrap bug

When booting 4.3 BSD Quasijarus, there is a bug (although VMS, NetBSD revisions above 1.6 or so, and Ultrix-32 all boot fine); it hangs inside udcmd() in sys/vaxstand/uda.c.

The fix is to change line 155 from:

    if(u->uda_ca.ca_rspint == 0)

to:

    if(u->uda_ca.ca_rspdc & MSCP_OWN)

Re-build the bootstrap, and then run disklabel to update the copy on the disk.

External links