SeaDAC 8221

Modbus Function	Valid Range	Description
(0x02) Read Discrete Inputs	0 - 15	Reads the opto-isolated inputs.
(0x01) Read Coils	0 - 15	Reads the state of reed relay outputs.
(0x05) Write Single Coil	0 - 15	Writes to a single reed relay output.
(0x0F) Write Multiple Coils	0 - 15	Writes multiple reed relay outputs.