Debug Port; Auxiliary Uart Port - Quectel M85 Hardware Design

3.7.2. Debug Port

Debug Port
 Two lines: DBG_TXD and DBG_RXD
 It outputs log information automatically.
 Debug Port is only used for firmware debugging and its baud rate must be configured as 460800bps.
Module

3.7.3. Auxiliary UART Port

Auxiliary UART Port
 Two data lines: TXD_AUX and RXD_AUX
 Auxiliary UART port is used for AT command only and does not support GPRS data, CSD FAX,
Multiplexing function etc.
 Auxiliary UART port supports the communication baud rates as the following:
4800, 9600, 14400, 19200, 28800, 38400, 57600, 115200.
 The default baud rate setting is 115200bps, and does not support autobauding. The baud rate can be
modified by AT+QSEDCB command. For more details, please refer to the document [1].
M85_Hardware_Design
DBG_TXD
DBG_RXD
GND
Figure 22: Reference Design for Debug Port
Confidential / Released
GSM/GPRS Module
M85 Hardware Design
Peripheral
TXD
RXD
GND
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