|I2CDETECT(8)||System Manager's Manual||I2CDETECT(8)|
i2cdetect - detect I2C chips
i2cdetect [-y] [-a] [-q|-r]
i2cbus [first last]
i2cdetect -F i2cbus
i2cdetect is a userspace program to scan an I2C bus for devices. It outputs a table with the list of detected devices on the specified bus. i2cbus indicates the number or name of the I2C bus to be scanned, and should correspond to one of the busses listed by i2cdetect -l. The optional parameters first and last restrict the scanning range (default: from 0x08 to 0x77).
As there is no standard I2C detection command, i2cdetect uses arbitrary SMBus commands (namely SMBus quick write and SMBus receive byte) to probe for devices. By default, the command used is the one believed to be the safest for each address. See options -q and -r to change this behavior.
i2cdetect can also be used to query the functionalities of an I2C bus (see option -F.)
This program can confuse your I2C bus, cause data loss and worse!
Each cell in the output table will contain one of the following symbols:
List all available I2C busses:
# i2cdetect -l
Immediately scan the standard addresses on I2C bus 9 (i2c-9), using the default method for each address (no user confirmation):
# i2cdetect -y 9
Query the functionalities of I2C bus 1 (i2c-1):
# i2cdetect -F 1
Scan addresses 0x10 to 0x17 on the I2C bus named "SMBus I801 adapter at efa0", using the "receive byte" method, after user confirmation:
# i2cdetect -r "SMBus I801 adapter at efa0" 0x10 0x17
To report bugs or send fixes, please write to the Linux I2C mailing list <firstname.lastname@example.org> with Cc to the current maintainer: Jean Delvare <email@example.com>.
i2cdump(8), i2cget(8), i2cset(8), i2ctransfer(8), sensors-detect(8)
Frodo Looijaard, Mark D. Studebaker and Jean Delvare
This manual page was originally written by Aurelien Jarno <firstname.lastname@example.org>, for the Debian GNU/Linux system.