ASC(4)                 OpenBSD Programmer's Manual (VAX)                ASC(4)

NAME
     asc - VAXstation 4000 SCSI controller

SYNOPSIS
     asc* at vsbus? csr 0x200c0080 (VS4000/60 or VLC)
     asc* at vsbus? csr 0x25000080 (VS4000/9x)
     scsibus* at asc?

DESCRIPTION
     The asc driver provides support for the NCR 53c94-based SCSI host adapter
     on the VAXstation 4000 series, and for the PMAZ-AA and related TURBOchan-
     nel SCSI adapter option boards (also on the VAXstation 4000 series models
     which include support for the TURBOchannel adapter.

CONFIGURATION
     The asc driver supports the following flags for use in config(8) files:

     bits 0-7:    disable disconnect/reselect for the corresponding SCSI tar-
                  get
     bits 16-23:  disable synchronous negotiation for SCSI target

     "Target" is synonymous with SCSI ID number.

     Note that SCSI tape drives should be allowed to perform disconnect/rese-
     lect or performance will suffer.

SEE ALSO
     cd(4), ch(4), intro(4), scsi(4), sd(4), ss(4), st(4), uk(4)

HISTORY
     The asc driver first appeared in NetBSD 1.5.  It has been supported in
     OpenBSD since release 2.8.

OpenBSD 4.7                      May 31, 2007                                1
