... It supports RS232, RS485 (or RS422) and ZigBee port that can conveniently and transparently connect one device to a ... been widely used on M2M fields, such as intelligent transportation, smart grid, industrial automation, telemetry, finance, POS, water supply, ... (Extendable)SRAM256KB(Extendable) Interface TypeItemContentSerial 1 RS232 port and 1 RS485(orRS422) port, 15KV ESD protectionData bits: 5, 6 ,7 ...