Quectel BC660K-GL - UART Application

NB-IoT Module Series
BC660K-GL Hardware Design
BC660K-GL_Hardware_Design 27 / 57
3.7.1. Main UART Port
The main UART port supports AT command communication, data transmission and firmware upgrade.
⚫ Default baud rate: 115200 bps
⚫ Supported baud rates: 2400 bps, 4800 bps, 9600 bps, 19200 bps, 38400 bps, 57600 bps, 115200
bps, 230400 bps, 460800 bps
When the port is used for firmware upgrade, the baud rate is 921600 bps by default.
When the module is in Deep Sleep/Light Sleep mode, you can wake up it by sending AT commands
through the main UART port. It is recommended to keep sending the command AT until OK is returned
before sending AT commands for other services.
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 11: Reference Design for Main UART Port
3.7.2. Debug UART Port
Through debug tools, the debug UART port can be used to output logs for firmware debugging. Its baud
rate is 6 Mbps by default. The following is a reference design of debug UART port.
DBG_TXD
39
Debug UART transmit
Ring Indication
RI
20
Ring indication (when there is a SMS or a URC
output, the module will inform DTE with the RI pin)