... connection for customers. It supports several ways that trigger DTU to be online, including audio, SMS and data. Also, it ... codec B. Hardware System 1. high-powered MCU, 100M2. Interface:RS232/RS485 serial port, rates: 110~230400bits/sIndicator lights: Power, ... configure and control17. Easy to upgrade firmware18. Support multi OS, such as WINDOWS, LINUX, SCO UNIX etc. CDMA2000 1X EVDO DTU(RS232/485)