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Driver for BusLogic/Mylex Multimaster host adapters (QNX Neutrino)

Note: You must be root to start this driver.


devb-btmm [cam option[,option]...]
          [cdrom  option[,option]...]
          [disk option[,option]...]
          [optical option[,option]...]
          [btmm option[,option]...]
          [blk option[,option]...] &

Runs on:



Note: Use commas (,) to separate the options. You can put the cam, cdrom, disk, optical, btmm, and blk groups of options in any order.

cam options

Enable Logical Unit Number (LUN) scan for the devices specified in mask. The mask is a hex bitmask specifying which IDs to scan for; the default is 0x00.
Be quiet: don't display any information on startup.
Be verbose: display full information about SCSI units (devices) on startup.

cdrom options

The cdrom options control the driver's interface to If specified, they must follow the cdrom keyword.

disk options

The disk options control the driver's interface to If specified, they must follow the disk keyword.

optical options

The optical options control the driver's interface to If specified, they must follow the optical keyword.

btmm options

The btmm options control the drivers interface to the BusLogic/Mylex Multimaster series controllers. If you've installed multiple controllers, you can repeat these options for each controller. Remember, however, to specify the btmm keyword before each controller's set of options.

The I/O port of the interface. By default, it's detected automatically.
Use this for clones; the default is for the driver to attempt to verify the type of card, and clone disables this check.
Use the specified DMA channel.
Assume that the controller is using this interrupt. Default is 11.
Reset the controller and SCSI bus at initialization time.
Specify the SCSI ID used by the controller. Default is 7.

blk options

The blk options control If specified, they must follow the blk keyword.


The devb-btmm driver is for the BusLogic/Mylex Multimaster and compatible SCSI controllers.

Controllers supported by this driver include, but aren't necessarily limited to:

Controller Description
BT-440C Bus master VL SCSI host adapter.
BT-445C Bus master VL SCSI host adapter with floppy controller.
BT-542B Bus master ISA SCSI host adapter with floppy controller.
BT-542D Bus master ISA-to-Fast SCSI host adapter with floppy controller.
BT-545C Bus master ISA SCSI host adapter with floppy controller.
BT-545S Bus master ISA-to-Fast SCSI host adapter with floppy controller.
BT-646S Bus master MCA SCSI host adapter.
BT-747S Bus master EISA SCSI host adapter.
BT-946C Bus master PCI-to-Fast SCSI host adapter with floppy controller.

The driver performs a scan, looking for installed units. All targets are scanned (0 to 7) and for each target, each LUN (Logical Unit Number) is scanned (0 to 7). Devices are numbered starting from 0, and each type of device is numbered separately.

The devb-btmm driver closes its standard input, standard output and standard error immediately after completing its initializations. Error messages may be produced during the initialization phase and are written to standard error.


Start the Multimaster driver:

devb-btmm &

Start the Multimaster driver with an I/O port of 0x330 and an interrupt of 11:

devb-btmm btmm ioport=0x330,irq=11 &


The devb-btmm driver causes to adopt various block special devices under /dev. These devices are normally named hdn (or cdn for CD-ROMs), where n is the physical unit number of the device.

This driver could also require the following shared objects:

Binary Required For CD-ROM access For hard-disk access Always

Exit status:

The devb-btmm driver terminates only if an error occurs during startup, or if it has successfully forked itself upon startup because it hadn't been initially started in the background.

The devb-btmm driver wasn't started in the background and therefore forked itself. The original process terminated with a zero exit status, the forked process continued.
> 0
An error occurred during startup.


The BusLogic/Mylex Multimaster host adapter is compatible with the Adaptec AIC-154x SCSI controller. On startup, the enumerators recognize this adapter as the Adaptec card but devb-aha4 will fail unless it includes the clone option.

Unless overridden with the blk automount= option (see, devices are mounted as:

Device Mountpoint Filesystem type
/dev/hd0t77 /hd qnx4
/dev/cd0 /cd cd
/dev/hd0t6 /dos dos
/dev/hd0t11 /dos dos

While there's no limit to the size of a disk or partition, I/O (i.e. the lseek(), read() and write() functions) is currently limited to 2 gigabytes per partition (or disk). This I/O limit has no effect on the partition size for mounted filesystems.

Known supported functions include:

chmod(), chown(), close(), closedir(), creat(), devctl(), dup(), dup2(), fcntl(), fpathconf(), fstat(), lseek(), mkdir(), mkfifo(), mknod(), open(), opendir(), pathconf(), read(), readdir(), readlink(), rewinddir(), rmdir(), stat(), symlink(), unlink() (not supported for directories), utime(), write()

Note that certain calls (such as pipe() as well as read() and write() on FIFOs) may require the pipe manager.

See also:

cam-*, devb-*, fs-*,

Filesystems and block I/O (devb-*) drivers in the Fine-Tuning Your System chapter of the QNX Neutrino User's Guide