The following Modbus function codes are supported by the M340 PLC line:
Function Code Description

1 Read output bits
2 Read input bits
3 Read output registers
4 Read input registers
15 Write output bits
16 Write registers

The following Modbus function codes are supported by the M340 PLC line:
Function Code Description

1 Read output bits
2 Read input bits
3 Read output registers
4 Read input registers
15 Write output bits
16 Write registers