SIM802 Hardware Design
SIM802_HD_V2.01
12.01.2010
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Figure 19: Connection of serial ports
Note: The RTS PIN must be connected to the GND in the customer circuit when only the TXD
and RXD are used in the Serial Port communication.
3.9.1 Main serial port and Debug serial port supporting
Main serial port
z
Seven lines on Serial Port Interface
z
Contains Data lines TXD and RXD, State lines RTS and CTS, Control lines DTR, DCD and
RING;
z
Serial port can be used for CSD FAX, GPRS service and send AT command of controlling
module. Also serial port can be used for multiplexing function. SIM802 supports only basic
mode of multiplexing so far.
z
Serial Port supports the communication rate as following:
300, 1200, 2400, 4800, 9600, 19200, 38400, 57600, 115200 Default as 115200bps.
z
Autobauding supports baud rates as following:
4800, 9600, 19200, 38400, 57600 and 115200bps
Debug serial port
z
Two lines on Serial Port Interface
z
Only contains Data lines /TXD and /RXD
z
Debug Port only used for debugging. It cannot be used for CSD call, FAX call. And the
Debug port can not use multiplexing function;
z
Debug port supports the communication rate as following:
