ASC(4) | Device Drivers Manual (vax) | ASC(4)

# NAME

`asc` —
VAXstation 4000 SCSI controller

# SYNOPSIS

`asc* at vsbus? csr 0x200c0080` (VS-4000/60 or VLC)
`asc* at vsbus? csr 0x25000080` (VS-4000/9x)
`asc* at tc?` (Not yet supported)
`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 TURBOchannel 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(1) files:

bits 0-7:
  disable disconnect/reselect for the corresponding SCSI target
bits 8-15:
  disable synchronous negotiation for SCSI target

“Target” is synonymous with SCSI ID number.

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

# SEE ALSO

cd(4), ch(4), esp(4), scsi(4), sd(4), st(4), vax/intro(4)

# HISTORY

The `asc` driver first appeared in NetBSD 1.5.

February 17, 2017 | NetBSD 9.4