User's Manual

L710 EVB User Manual

Figure 4-3： WDOG key

5 Application interface

5.1 UART DB9 Interface

There is a DB9 COM port on the L710 development board, and its signal pin is consistent with the

signal on the L710 module. The serial interface as the main serial port can support complete 9 -

line RS232. The COMS 1.8v level on the L710 module is converted to the standard RS232 level

via serial port level conversion chip SP3238. Users can connect to PC or other terminal devices

through DB9 serial port cable provided for serial port communication. Main serial port (this

function has not been opened yet) supports hardware flow control for AT instruction, data

transmission, etc. When using, you need to dial the switch S4 to the right as shown in the arrow

direction below.