:man| Alphabetical   Categories   About us 
BT (4) | Special files and drivers | Unix Manual Pages | :man


bt - Buslogic/Mylex MultiMaster SCSI host adapter driver


See Also


.Cd device bt
.Cd device scbus

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


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 PCI192ULtra SCSI-3
BT-958 PCI192Wide ULtra SCSI-3
BT-958D PCI192Wide Differential ULtra SCSI-3

MultiMaster "C" Series Host Adapters:

"Adapter Bus Commands Description"
BT-946C PCI100Fast SCSI-2
BT-956C PCI100Wide Fast SCSI-2
BT-956CD PCI100Wide Differential Fast SCSI-2
BT-445C VLB100Fast SCSI-2
BT-747C EISA 100Fast SCSI-2
BT-757C EISA 100Wide Fast SCSI-2
BT-757CD EISA 100Wide Differential Fast SCSI-2
BT-545C ISA 50Fast SCSI-2
BT-540CF ISA 50Fast SCSI-2

MultiMaster "S" Series Host Adapters:

"Adapter Bus Commands Description"
BT-445S VLB 30Fast SCSI-2
BT-747S EISA30Fast SCSI-2
BT-747D EISA30Differential Fast SCSI-2
BT-757S EISA30Wide Fast SCSI-2
BT-757D EISA30Wide Differential Fast SCSI-2
BT-545S ISA 30Fast SCSI-2
BT-542D ISA 30Differential Fast SCSI-2
BT-742A EISA30SCSI-2 (742A revision H)
BT-542B ISA 30SCSI-2 (542B revision H)

MultiMaster "A" Series Host Adapters:

"Adapter Bus Commands Description"
BT-742A EISA30SCSI-2 (742A revisions A - G)
BT-542B ISA 30SCSI-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.


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-742A
  • BusLogic BT-742A
  • BusLogic BT-747C
  • BusLogic BT-747D
  • BusLogic BT-747S
  • BusLogic BT-757C
  • BusLogic BT-757CD
  • BusLogic BT-757D
  • BusLogic BT-757S
  • BusLogic BT-946C
  • BusLogic BT-948
  • BusLogic BT-956C
  • BusLogic BT-956CD
  • BusLogic BT-958
  • BusLogic BT-958D
  • Storage Dimensions SDC3211B / SDC3211F

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


sys/dev/buslogic/bt.c Core Driver Implementation
sys/dev/buslogic/btreg.h MultiMaster Register Set and Core Driver Data Structures
sys/pci/bt_pci.c PCI Bus Driver Attachment
sys/i386/eisa/bt_eisa.c EISA Bus Driver Attachment
sys/i386/isa/bt_isa.c ISA/VL Bus Driver Attachment


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



Created by Blin Media, 2008-2013