AHD(4)                    OpenBSD Programmer's Manual                   AHD(4)

NAME
     ahd - Adaptec PCI/PCI-X AIC79xx-based Ultra320 SCSI interface

SYNOPSIS
     ahd* at pci?
     scsibus* at ahd?

DESCRIPTION
     ahd provides access to the SCSI bus(es) connected to Adaptec AIC79xx host
     adapter chips.

     ahd supports narrow and wide buses; synchronous and asynchronous opera-
     tion; fast, ultra, ultra2, ultra160, and ultra320 (packetized) transfers;
     tagged queuing and 512 SCBs.

     ahd does not support target mode operation.

     The ahd driver supports the following:

           o   Adaptec AIC7901 host adapter chip
           o   Adaptec AIC7901A host adapter chip
           o   Adaptec AIC7902 host adapter chip
           o   Adaptec 29320 host adapter
           o   Adaptec 39320 host adapter
           o   Many motherboards with on-board SCSI support

     To compile in debugging code:

           option AHD_DEBUG
           option AHD_DEBUG_OPTS=<bitmask of options>

     The AHD_DEBUG_OPTS option is used to control which diagnostic messages
     are printed to the console when AHD_DEBUG is enabled.  Logically OR the
     following bits together:

           Value    Function
           0x0001   Show miscellaneous information
           0x0002   Show sense data
           0x0004   Show Serial EEPROM contents
           0x0008   Show bus termination settings
           0x0010   Show host memory usage
           0x0020   Show SCSI protocol messages
           0x0040   Show mode pointer of the chip register window
           0x0080   Show selection timeouts
           0x0100   Show FIFO usage messages
           0x0200   Show Queue Full status
           0x0400   Show SCB queue status
           0x0800   Show inbound packet information
           0x1000   Show S/G list information
           0x2000   Enable extra diagnostic code in the firmware

     Per target configuration performed in the SCSI-Select menu, accessible at
     boot, is honored by this driver.  This includes synchronous/asynchronous
     transfers, maximum synchronous negotiation rate, wide transfers, discon-
     nection, and the host adapters SCSI ID.

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

HISTORY
     The ahd driver was ported from FreeBSD 4.7 and first appeared in
     OpenBSD 3.6.

AUTHORS
     The ahd driver, the AIC7xxx sequencer-code assembler, and the firmware
     running on the aic79xx chips was written by Justin T. Gibbs.

     OpenBSD port by Milos Urbanek, Kenneth R. Westerback & Marco Peereboom.

OpenBSD 4.7                     January 3, 2010                              2
