Auxiliary Uart Port; Uart Application - Quectel BC66 Hardware Design

3.8.3. Auxiliary UART Port

The auxiliary UART port is designed as a general purpose UART for communication with DTE. It also
supports log output for firmware debugging, and hardware flow control*. Its baud rate is 115200bps by
default. The following is a reference design of auxiliary UART port.

3.8.4. UART Application

The module provides 1.8V UART interfaces. A level translator should be used if the application is
equipped with a 3.3V UART interface. A level translator TXS0108EPWR provided by Texas Instruments
(please visit http://www.ti.com for more information) is recommended. The following figure shows a
reference design.
BC66_Hardware_Design
Module
TXD_DBG
RXD_DBG
GND
Figure 15: Reference Design of Debug UART Port
Module
TXD_AUX
RXD_AUX
GND
Figure 16: Reference Design of Auxiliary UART Port
NB-IoT Module Series
BC66 Hardware Design
DTE
TXD
RXD
GND
DTE
TXD
RXD
GND
27 / 57