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.\" Copyright (c) 1994 Wilko Bulte
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.\" $FreeBSD: src/share/man/man4/ahb.4,v 1.13.4.5 2001/10/01 13:07:22 dd Exp $
.\" $DragonFly: src/share/man/man4/ahb.4,v 1.2 2003/06/17 04:36:58 dillon Exp $
.\"
.Dd October 15, 1998
.Dt AHB 4
.Os
.Sh NAME
.Nm ahb
.Nd Adaptec EISA SCSI host adapter driver
.Sh SYNOPSIS
.Cd device ahb
.Cd device scbus0 at ahb0
.Sh DESCRIPTION
This driver provides access to the
.Tn SCSI
bus connected to an Adaptec
174x hostadapter in
.Dq Em enhanced
mode.
Tagged queueing and synchronous SCSI transfers are supported.
.Sh CAVEATS
The Adaptec 174X is very sensitive to SCSI bus termination and cable
length.  It may also have difficulties operating with some modern devices
that, due to their speed, expose timing problems in the controller.  There
are no known mechanisms for working around device incompatibilities of
this nature.
.Sh SEE ALSO
.Xr aha 4 ,
.Xr ahc 4 ,
.Xr cd 4 ,
.Xr da 4 ,
.Xr sa 4 ,
.Xr scsi 4
.Sh AUTHORS
The
.Nm
driver was written by
.An Justin T. Gibbs .