usbrelay - Man Page

control or query USB HID relays


usbrelay [OPTION...] [ACTION...]


usbrelay allows for querying and setting the state of USB HID electrical relays. If no ACTION is passed, the state of all relays is printed to stdout. RELID_N=[0|1] sets the N-th relay on module RELID to off or on.

Multiple actions can be performed with one command


usbrelay REL0A_1=0 REL0A_2=1 REL0B_2=0...

Note that the RELID must only contain the characters A-Z0-9. Change the RELID using the device file as the RELID if the relay has illegal characters (See below).

The Relay module ID can be changed on DCTTECH relays:

RELID_0=NEWID sets the relay RELID to NEWID


/dev/hidrawX_0=NEWID (Substitute X for the device path shown with the -d option)


-d,  --debug

Produce debugging output

-q,  --quiet

Suppress output

-?,  --help

Print the help menu


Print a usage description

-V,  --version

Print the program version

Referenced By


24 Jan 2022