This Coolmay touch screen manual explains how to configure Modbus RTU communication as master or slave, covering parameters, function codes, and register…
The document provides step‑by‑step instructions for setting up Modbus RTU communication on Coolmay touch screens. It describes how to configure communication ports, device types, baud rates and other parameters for both master and slave modes.
The manual is organized into sections for master configuration, slave configuration, and special registers. It lists the supported Modbus function codes, explains multi‑device communication settings, and shows how to set slave IDs and register address ranges. This manual is written in Chinese.
| RS232 communication port | COM1 |
|---|---|
| RS485 communication port | COM2 |
| Device type (master mode) | ModbusRTU Slave |
| Device type (slave mode) | ModbusRTU Master |
| Default attempt count | 8 |
| Data register address range | 4x0‑4x65000 |
| Bit address range | 0x0‑0x65000 |
Open the menu Application → Set Work Parameters → Communication Settings, choose COM1 or COM2, set the device type, baud rate, timeout, parity, data bits and stop bits to match the other device.
The touch screen supports function codes 01 (Read Coils), 03 (Read Holding Registers), 05 (Write Single Coil), 06 (Write Single Register) and 16 (Write Multiple Registers).
When using the RS232 port (COM1) only one slave can be connected; for multiple slaves you must use the RS485 port (COM2).
Add a function key that jumps to system menu 255, then compile and download the program; the screen will open the menu where you can set the slave ID.