Quectel BC65 - Main UART Interface; Debug UART Interface

NB-IoT Module Series
BC65 Hardware Design
BC65_Hardware_Design 28 / 55
3.8.1. Main UART Interface
The main UART interface can be used for AT command communication and data transmission, and in
such case, the baud rates should be 4800 bps, 9600 bps (default) and 57600 bps. The main UART
interface is available in active mode and idle mode.
The figure below shows the connection between DCE and DTE.
MAIN_TXD
MAIN_RXD
TXD
RXD
Module (DCE)
Serial portMain port
GND GND
DTE
Figure 14: Reference Design for Main UART Interface
3.8.2. Debug UART Interface
Through debug tools, the debug UART interface can be used to output logs for firmware debugging and
upgrading. The baud rate is 921600 bps by default. The following figure is a reference design for debug
UART interface.
DTE
TXD
RXD
GND
Module
DBG_TXD
DBG_RXD
GND
Figure 15: Reference Design for Debug UART Interface