RS232M Module 13.2 is an expansion module of RS232 serial communication with isolation, using the scheme of TD301D232H serial port conversion chip + male DB9 interface to realize the interface conversion between RS232 and TTL/CMOS logic level signals, and using F0505S-2WR3 DC-DC power module to realize electrical and noise isolation functions, toggle switch and coding switch It can realize the pass-through or cross-switching of DB9 signal lines and the switching of serial interfaces to meet different connection needs. The module has a built-in DC power input socket and a corresponding DC-DC circuit to provide power to the entire device. The product is suitable for industrial automation, instrumentation, medical equipment and communication equipment.