ICP DAS USA PDS-220F Series User Manual page 45

Programmable Serial-to-Fiber Device Server
M2: Half-Slave Mode (Is situated between M0 and the M1 mode)
M2 is used for Virtual COM and TCP/IP connections. If only one client connects to the PDS-220Fx,
the operation mode same as M0 mode (Multi-echo, shared), refer to Section "M0: Transparent
Mode". If there are two or more clients connecting to the PDS-220Fx, the operation mode same as
M1 mode (Single-echo, Non-shared), refer to Section "M1: Slave Mode". PDS-220Fx sends data to
the last client when data is available but no request from any client.
M3: Modbus Gateway
When PDS-220FX is configured to Modbus Gateway, the operation mode will be automatically set
to M3 mode. The more detailed information regarding configuring Modbus Gateway, refer to
Section 4.4 "Modbus Gateway Settings" and Chatper 5 "Modbus Testing and Protocol".
PDS-220Fx Series User Manual Version 1.3, Oct. 2018 - 45 -