[Introduction]：The M31 series distributed IO host supports Modbus TCP and RTU protocols, allows up to 5 clients to access simultaneously, and is compatible with function codes 01, 02, 03, 04, 05, 06, 15, and 16. Its expandable design enables the connection of up to 16 IO expansion modules as needed, eliminating the need to purchase a complete system. This reduces costs while facilitating easy integration into existing site environments. The device includes built-in status diagnostics for real-time monitoring of IO module communication status.