NAME
candump - manual page for candump 2023.03-1
SYNOPSIS
candump [options] <CAN interface>+
DESCRIPTION
candump - dump CAN bus traffic.
-
(use CTRL-C to terminate candump)
OPTIONS
- -t <type>
-
(timestamp: (a)bsolute/(d)elta/(z)ero/(A)bsolute w date)
- -H
-
(read hardware timestamps instead of system timestamps)
- -c
-
(increment color mode level)
- -i
-
(binary output - may exceed 80 chars/line)
- -a
-
(enable additional ASCII output)
- -S
-
(swap byte order in printed CAN data[] - marked with '`' )
- -s <level>
-
(silent mode - 0: off (default) 1: animation 2: silent)
- -l
-
(log CAN-frames into file. Sets '-s 2' by default)
- -f <fname>
-
(log CAN-frames into file <fname>. Sets '-s 2' by default)
- -L
-
(use log file format on stdout)
- -n <count>
-
(terminate after reception of <count> CAN frames)
- -r <size>
-
(set socket receive buffer to <size>)
- -D
-
(Don't exit if a "detected" can device goes down)
- -d
-
(monitor dropped CAN frames)
- -e
-
(dump CAN error frames in human-readable format)
- -8
-
(display raw DLC values in {} for Classical CAN)
- -x
-
(print extra message infos, rx/tx brs esi)
- -T <msecs>
-
(terminate after <msecs> if no frames were received)
Up to 16 CAN interfaces with optional filter sets can be specified on the commandline in the form: <ifname>[,filter]*
Filters:
-
Comma separated filters can be specified for each given CAN interface:
-
<can_id>:<can_mask>
-
(matches when <received_can_id> & mask == can_id & mask)
-
<can_id>~<can_mask>
-
(matches when <received_can_id> & mask != can_id & mask)
-
#<error_mask>
-
(set error frame filter, see include/linux/can/error.h)
-
[j|J]
-
(join the given CAN filters - logical AND semantic)
CAN IDs, masks and data content are given and expected in hexadecimal values. When the can_id is 8 digits long the CAN_EFF_FLAG is set for 29 bit EFF format. Without any given filter all data frames are received ('0:0' default filter).
Use interface name 'any' to receive from all CAN interfaces.
EXAMPLES
candump -c -c -ta can0,123:7FF,400:700,#000000FF can2,400~7F0 can3 can8
candump -l any,0~0,#FFFFFFFF
-
(log only error frames but no(!) data frames)
candump -l any,0:0,#FFFFFFFF
-
(log error frames and also all data frames)
candump vcan2,12345678:DFFFFFFF
-
(match only for extended CAN ID 12345678)
candump vcan2,123:7FF
-
(matches CAN ID 123 - including EFF and RTR frames)
candump vcan2,123:C00007FF
-
(matches CAN ID 123 - only SFF and non-RTR frames)