USB relay (ICSE013A)

USB relay (ICSE013A)

ximport ubuntu openwrt

usb relay (ICSE013A) Here is a small and inexpensive Linux friendly USB dual relay: ICStation ICSE013A, available on ebay for less than 5 USD.



  • USB micro-b
    • Used for power supply and USB-CDC
  • 4 pin header (not soldered) :
    • Power + RS232 signals @ 3.3V
    • pinout:
      • RX (connect to master TX)
      • TX (connect to master RX)
      • GND
      • 5V (power supply)

Relay side:

  • 2x 3 screw terminal
    • NO
    • C
    • NC

Onboard devices:

  • 2x relay Songle SRD-05VDC-SL-C
  • 1x USB to serial chip Prolific 2303HX
  • 1x probably a microcontroller ??? ST78596

Serial configuration: 9600,8,n,1

Protocol: Say hello and wait some time :

 echo -n "P" > /dev/ttyUSB0 && sleep 0.5

Should reply 0xAD for dual channel

Say start and wait some time :

echo -n "Q" > /dev/ttyUSB0 && sleep 0.5

Now the module wait for binary values until power is removed.

Set values (one bit per relay):

echo -n "\x01" > /dev/ttyUSB0 && sleep 0.5

This will also work using openwrt, using this driver:

opkg install kmod-usb-serial-pl2303


Question, remark, bug? Don't hesitate to contact me or report a bug.