MC Protocol Serial — PLC setup
Configure the MELSEC serial communication module before connecting with the MC Protocol Serial library. Unlike the three Ethernet protocols, the physical layer is part of the setup: the frame format, baud rate, and character format on the PLC module must match the client exactly, and RS-232C levels must be converted before an MCU UART is connected.
Power cycle the PLC or module after parameter changes if the PLC or engineering tool requires it.
Setup pages
| Page | Use it for |
|---|---|
| Serial modules | Minimum module checklist, the verified host-side wiring shape, and the MCU-side shape using a level shifter. |
| Supported registers | Device families the serial library addresses, and how they are encoded. |
| MC Protocol Serial Troubleshooting & Codes | NAK and error responses observed during live verification, with the first check for each. |
After the PLC is configured
MC Protocol Serial is implemented in C++ for Arduino and PlatformIO targets, and the same library builds host-side for bring-up tools.
C++ (Arduino/PlatformIO) Getting started
PLC Scope does not cover MC Protocol Serial. For a first read-only check on a
serial PLC, use the bring-up scripts in
examples/linux_cli
of the MC Protocol Serial C++ library.