FWCONTROL(8) FreeBSD System Manager's Manual FWCONTROL(8)


fwcontrolFireWire control utility


fwcontrol [ -u bus_num][ -prt][ -c node][ -d node][ -o node][ -s node][ -l file][ -f node][ -g gap_count][ -b pri_req][ -M mode][ -R filename][ -S filename][ -m EUI64 | hostname]


The fwcontrol utility is designed to provide a way for users to access and control the FreeBSD FireWire subsystem. Without options, fwcontrol will output a list of devices that are/were connected to the bus.

The following options are available:

-u bus_num
Specify the FireWire bus number to be operated on. The default is bus 0.
Initiate bus reset.
Show the topology map.
Dump PHY registers.
-c node
Show the configuration ROM on the node.
-d node
Hex dump of the configuration ROM.
-o node
Send a link-on PHY packet to the node.
-s node
Write to the RESET_START register on the node.
-l file
Load hex dump file of the configuration ROM and parse it.
-f node
Force specified node to be the root node on the next bus reset by sending a PHY config packet. Valid values are 0 - 63.
-g gap_count
Broadcast new gap_count by sending a PHY_config packet. By default this value is 63 on all nodes. Valid values are 0 - 63.
-i pri_req
Set the PRIORITY_BUDGET register on all supported nodes.
-M mode
Explicitly specify either dv or mpeg mode for the incoming stream. Only meaningful in case of and must precede the -R option. If not specified, the program will try to guess. In case of “format 0x20” error, try to force the “mpeg” mode.
-R filename
Receive DV or MPEG TS stream and dump it to a file. Use ^C to stop the receiving. Some DV cameras seem not to send the stream if a bus manager exists. If it is impossible to get the stream, try the following commands:

sysctl hw.firewire.try_bmr=0 
fwcontrol -r

The resulting file contains raw DV data excluding isochronous header and CIP header. It can be handled by libdv in the FreeBSD Ports Collection. Resulting MPEG TS stream can be played and sent over a network using the VideoLAN vlc tool in the FreeBSD Ports Collection. The stream can be piped directly to vlc, see EXAMPLES.

-S filename
Send a DV file as isochronous stream.
-m EUI64 | hostname
Set default fwmem target. Hostname will be converted to EUI64 using eui64(5).




Each DV frame has a fixed size and it is easy to edit the frame order.

fwcontrol -R original.dv

Receive a DV stream with DV camera attached.

dd if=original.dv of=first.dv bs=120000 count=30

Get first 30 frames(NTSC).

dd if=original.dv of=second.dv bs=120000 skip=30 count=30

Get second 30 frames(NTSC).

cat second.dv first.dv | fwcontrol -S /dev/stdin

Swap first and second 30 frames and send them to DV recorder.

For PAL, replace “ bs=120000” with “ bs=144000”.

fwcontrol -R file.m2t

Receive an MPEG TS stream from a camera producing MPEG transport stream. This has been tested with SONY HDR-FX1E camera that produces HD MPEG-2 stream at 25 Mbps bandwidth.

To send the stream from the camera over the network using TCP (which surprisingly works better with vlc), you can use

fwcontrol -R - | nc 9000

with netcat from ports and to receive the stream, use

nc -l -p 9000 | vlc -

To netcast via UDP, you need to use buffer program from ports, since vlc is not fast enough to read UDP packets from buffers and thus it experiences dropouts when run directly. The sending side can use

fwcontrol -R - | nc 9000

and to receive the stream, use

nc -l -u -p 9000 | buffer -s 10k -b 1000 -m 20m -p 5 | vlc -

For more information on how to work with vlc see its docs.


The fwcontrol utility first appeared in FreeBSD 5.0.


Hidetoshi Shimokawa <simokawa@FreeBSD.org> Petr Holub <hopet@ics.muni.cz> - MPEG TS mode.


This utility is still under development and provided for debugging purposes. Especially MPEG TS reception support is very rudimental and supports only high-bandwidth MPEG-2 streams (fn field in CIP header equals 3).
September 12, 2008 FreeBSD