.\"	$OpenBSD: esp.4,v 1.8 2004/09/30 19:59:27 mickey Exp $
.\"
.\" Copyright (c) 1998 The OpenBSD Project
.\" All rights reserved.
.\"
.\"
.Dd March 4, 1998
.Dt ESP 4 sparc
.Os
.Sh NAME
.Nm esp
.Nd ESP NCR 53c94 on-board or SBus SCSI controller
.Sh SYNOPSIS
.Cd "dma0 at obio0 addr 0xfa001000 level 4             " Pq sun4/300
.Cd "esp0 at obio0 addr 0xfa000000 level 4 flags 0xff0f"
.Cd ""
.Cd "dma0 at sbus0                                     " Pq on-board
.Cd "esp0 at sbus0 flags 0xff0f                        " Pq sun4c
.Cd "esp0 at dma0 flags 0xff0f                         " Pq sun4m
.Cd ""
.Cd "dma* at sbus?                                     " Pq "SBus SCSI"
.Cd "esp* at sbus? flags 0xff0f                        " Pq "two flavours"
.Cd "esp* at dma? flags 0xff0f                         " Pq "depending on model"
.Sh DESCRIPTION
The
.Nm
is an on-board or SBus SCSI controller based on the NCR 53c94 chip, found
on Sun 4/300, sun4c and sun4m workstations.
.Sh DEVICE FLAGS
.Bl -tag -width "Bits XX-XX" -compact
.It Bits 0-7
Disable disconnect/reselect for the corresponding target
.It Bits 8-15
Disable synchronous negotiation for target "[bit - 8]"
.El
.Pp
The
.Nm
device flags may be OR'd together to enable any combination of
the features listed above.
Targets 4 through 7 typically have disconnect/reselect enabled on the premise
that tape devices normally have one of these targets.
Tape devices should be allowed to disconnect for the SCSI bus to operate
acceptably.
.Sh SEE ALSO
.Xr cd 4 ,
.Xr ch 4 ,
.Xr intro 4 ,
.Xr sbus 4 ,
.Xr scsi 4 ,
.Xr sd 4 ,
.Xr si 4 ,
.Xr st 4 ,
.Xr sw 4 ,
.Xr uk 4