btmon - Man Page

Bluetooth monitor


btmon [Options ...]


The  btmon(1) command  provides  access  to the Bluetooth subsystem monitor infrastructure for reading HCI traces.


-r FILE--read FILE

Read traces in btsnoop format from FILE.

-w FILE--write FILE

Save traces in btsnoop format to FILE.

-a FILE--analyze FILE

Analyze traces in btsnoop format from FILE. It displays the devices found in the FILE with its packets by type.

-s SOCKET--server SOCKET

Start monitor server socket.


Show only priority or lower for user log.

6Information (Default)
7Debug. debug can be used.
-i NUM--index NUM

Show only specified controller. hciNUM is also acceptable. This is useful to capture the traces from the specific controller when the multiple controllers are presented.

-d TTY--tty TTY

Read data from TTY.


Set TTY speed. The default SPEED is 115300


Set the default company identifier. The COMPID is a unique number assigned by the Bluetooth SIG to a member company and can be found/searched from the Bluetooth SIG webpage.

For example, Intel is 2 and Realtek is 93.

-M,  --mgmt

Open channel for mgmt events.

-t,  --time

Show a time instead of time offset.

-T,  --date

Show a time and date information instead of time offset.

-S,  --sco

Dump SCO traffic in raw hex format.

-A,  --a2dp

Dump A2DP stream traffic in a raw hex format.

-E IP--ellisys IP

Send Ellisys HCI Injection.

-P,  --no-pager

Disable pager usage while reading the log file.


Read data from RTT.  Each options are comma(,) seprated without spaces.

DEVICERequired. Set the target device.
SERIALNO(Optional) Set the USB serial number. Default is 0.
INTERFACE(Optional) Target interface. Default is swd.
SPEED(Optional) Set target interface speed in kHz. Default is 1000.

RTT control block parameters. Each options are comma(,) seprated without spaces.

ADDRESS(Optional) Address of RTT buffer. Default is 0x00
AREA(Optional) Size of range to search in RTT buffer. Default is 0
NAME(Optional) Buffer name. Default is btmonitor
-C WIDTH--columns WIDTH

Output width if not a terminal

-c MODE--color MODE

Set output color. The possible MODE values are: auto|always|never.

Default value is auto

-v,  --version

Show version

-h,  --help

Show help options


Capture the traces from hci0 to hcidump.log file

$ btmon -i hci0 -w hcidump.log

Open the trace file

$ btmon -r hcidump.log


Reporting Bugs


Marcel Holtmann <>, Tedd Ho-Jeong An <>


April 2021 BlueZ Linux System Administration