... Functions & Features of the GPRS DTU:GPRS Data Transmission, real-time online data transfer, no distance limitation;Embedded 32 bit ARM9-MCU ... , TCP/IP protocol stack;Supports transparent and non-transparent data transfer;Supports point-to-point, Point–to–Multipoint, Multipoint-to ... TxD, RxD, RTS, CTS, DTR, DSR, DCD, GND), rate speed up to 230400 BPS;Supports PAP authentication and CHAP authentication ...