Product Info

NB-IoT Module Series
BC660K-GL Hardware Design
BC660K-GL_Hardware_Design
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3.7.1. Main UART Port
The main UART port supports AT command communication, data transmission and firmware upgrade.
 Default baud rate: 115200 bps
 Fixed 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 enters Deep Sleep/Light Sleep mode, it can wake up the module by sending AT
commands through the main serial port. It is generally recommended to send the command AT
continuously until OK is returned before sending AT commands to other services.
The figure below shows the connection between DCE and 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.
Figure 12: Reference Design of Debug UART Port