Manual

Commands
The USB-RLY16L operates with an easy to use command set as described in the table below. Most
commands are only a single byte and if applicable the USB-RLY16L will automatically send its
response. The only exception to this being the "Set relay states" command which requires an additional
desired states byte to be sent immediately after the command byte.
Command
Action
dec hex
90 5A
Get software version - returns 2 bytes, the first being the Module ID
which is 15, followed by the software version
91 5B
Get relay states - sends a single byte back to the controller, bit high
meaning the corresponding relay is in position 1
92 5C
Set relay states - the next single byte will set all relays states, All in
position 1 = 255 (11111111) All in position 0 = 0
93 5D
Get DC input voltage - returns the supply voltage as byte, this is fixed at
50 meaning 5.0V DC
100 64 All relays to position 1
101 65 Relay 1 to position 1
102 66 Relay 2 to position 1
103 67 Relay 3 to position 1
104 68 Relay 4 to position 1
105 69 Relay 5 to position 1
106 6A Relay 6 to position 1