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 scbus
device bt

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

AMI FastDisk Host Adapters that are true BusLogic MultiMaster clones are also supported by this driver.

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

FILES
/sys/dev/disk/buslogic/bt.c
    Core Driver Implementation
/sys/dev/disk/buslogic/btreg.h
    MultiMaster Register Set and Core Driver Data Structures
/sys/dev/disk/buslogic/bt_pci.c
    PCI Bus Driver Attachment

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

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

AUTHORS
-nosplit 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.