AHSC(4) | Device Drivers Manual (amiga) | AHSC(4)

# NAME

`ahsc` — A3000 low level SCSI interface

# SYNOPSIS

`ahsc0 at mainbus0`

# DESCRIPTION

The Amiga architecture uses a common machine independent scsi sub-system provided in the kernel source. The machine independent drivers that use this code access the hardware through a common interface. (see scsibus(4)) This common interface interacts with a machine dependent interface, such as `ahsc`, which then handles the hardware specific issues.

The `ahsc` interface handles things such as DMA and interrupts as well as actually sending commands, negotiating synchronous or asynchronous transfers and handling disconnect/reconnect of SCSI targets. The hardware that `ahsc` uses is based on the WD33c93 SCSI chip.

# DIAGNOSTICS

sbicwait TIMEO @%d with asr=x%x csr=x%x
  The 33c93 code (sbic) has been waiting too long for a SCSI chip operation to complete. %d is the line in the source file amiga/dev/sbic.c at which the SCSI chip timed-out. Asr and csr are status registers within the SCSI chip.
ahsc%d: abort %s: csr = 0x%02x, asr = 0x%02x
  A SCSI operation %s was aborted due to an error.
ahsc%d: csr == 0x%02i
  A error has occurred within the SCSI chip code.
ahsc%d: unexpected phase %d in icmd from %d
  The target described by ‘from %d’ has taken the SCSI bus into a phase which is not expected during polled IO.
ahsc%d: unexpected phase %d in icmd from %d
  The target described by ‘from %d’ has taken the SCSI bus into a phase which is not expected during DMA IO setup.

# SEE ALSO

scsibus(4)

# HISTORY

The `ahsc` interface first appeared in NetBSD 1.0

August 31, 1994 | NetBSD 11.0