BT(4)                  FreeBSD Kernel Interfaces Manual                  BT(4)

NAME
     bt - Buslogic/Mylex MultiMaster SCSI host adapter driver

SYNOPSIS
     To compile this driver into the kernel, place the following lines in your
     kernel configuration file:

           device isa
           device scbus
           device bt

           In /boot/device.hints:
           hint.bt.0.at="isa"
           hint.bt.0.port="0x330"

DEPRECATION NOTICE
     This driver is scheduled for removal prior to the release of
     FreeBSD 13.0.

DESCRIPTION
     This driver provides access to the SCSI bus connected to a Buslogic/Mylex
     MultiMaster or compatible controller:

           MultiMaster "W" Series Host Adapters:

           Adapter      Bus     Commands     Description
           BT-948       PCI     192          Ultra SCSI-3
           BT-958       PCI     192          Wide Ultra SCSI-3
           BT-958D      PCI     192          Wide Differential Ultra SCSI-3

           MultiMaster "C" Series Host Adapters:

           Adapter      Bus     Commands     Description
           BT-946C      PCI     100          Fast SCSI-2
           BT-956C      PCI     100          Wide Fast SCSI-2
           BT-956CD     PCI     100          Wide Differential Fast SCSI-2
           BT-445C      VLB     100          Fast SCSI-2
           BT-545C      ISA     50           Fast SCSI-2
           BT-540CF     ISA     50           Fast SCSI-2

           MultiMaster "S" Series Host Adapters:

           Adapter      Bus     Commands     Description
           BT-445S      VLB     30           Fast SCSI-2
           BT-545S      ISA     30           Fast SCSI-2
           BT-542D      ISA     30           Differential Fast SCSI-2
           BT-542B      ISA     30           SCSI-2 (542B revision H)

           MultiMaster "A" Series Host Adapters:

           Adapter      Bus     Commands     Description
           BT-542B      ISA     30           SCSI-2 (542B revisions A - G)

     Tagged queueing is supported on 'W' series adapters, 'C' series adapters
     with firmware of rev 4.42 and higher, and 'S' series adapters with
     firmware of rev 3.35 and higher.

     Boards with certain firmware revisions may lock up under heavy load to
     certain devices, especially if tagged queueing is used.  Should you
     encounter a problem with your adapter, contact Mylex technical support
     and ensure you have the latest firmware for your controller.

HARDWARE
     The bt driver supports the following BusLogic MultiMaster "W", "C", "S",
     and "A" series and compatible SCSI host adapters:

     •   BusLogic BT-445C
     •   BusLogic BT-445S
     •   BusLogic BT-540CF
     •   BusLogic BT-542B
     •   BusLogic BT-542B
     •   BusLogic BT-542D
     •   BusLogic BT-545C
     •   BusLogic BT-545S
     •   BusLogic/BusTek BT-640
     •   BusLogic BT-946C
     •   BusLogic BT-948
     •   BusLogic BT-956C
     •   BusLogic BT-956CD
     •   BusLogic BT-958
     •   BusLogic BT-958D
     •   Storage Dimensions SDC3211B / SDC3211F

SEE ALSO
     cd(4), da(4), sa(4), scsi(4)

HISTORY
     The bt driver first appeared in the 386BSD patch kit.

AUTHORS
     Julian Elischer wrote a driver for the Multimaster cards that appeared in
     the 386BSD patch kit.  The driver was rewritten by Justin T. Gibbs to
     take advantage of new board features and work with the CAM SCSI framework
     in FreeBSD 3.0.

     Special thanks to Leonard N. Zubkoff for writing such a complete and well
     documented Mylex/BusLogic MultiMaster driver for Linux.  Support in this
     driver for the wide range of MultiMaster controllers and firmware
     revisions, with their otherwise undocumented quirks, would not have been
     possible without his efforts.

FreeBSD 13.1-RELEASE-p6         August 18, 2020        FreeBSD 13.1-RELEASE-p6