RF-Star EFR32BG22, Manual

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EFR32BG22
www.szrfstar.com V1.6 - Jun., 2022
Shenzhen RF-star Technology Co., Ltd.
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3 UART Transparent Transmission Protocol (Bridge Mode)
The bridge mode means to set up a bi-directional communication way between the user MCU and the mobile devices
by the mutual connection between the serial port and the user MCU. Users can reset serial port baud rate and BLE
connection interval by the specified AT commands (see the clause “ AT Command ”). The module will have different data
handling capabilities, as per different serial port baud rates and BLE connection intervals.
1. The default hardware protocol of the serial port: 115200 bps, 8, no parity, 1 stop bit.
2. The serial port is enabled by default in other modes except for beacon mode . If the serial port needs to be
closed, please use the command "AT+SLEEP=0".
3. When the module serial port receives data and transmits it to the mobile device, there is no strict requirement for
the serial port data packet. When the RTS of the module is at a high level, it indicates that the receive buffer of the
serial port is full (maximum buffer is 3328 bytes), or the serial port is busy.
4. Data packets from a mobile device to the module must be sub-packed automatically (within 1 ~ 247 bytes per packet)
before sending. The module will transmit the packets to the master RXD in turn after receiving the packets.
5. Most serial port tools on the PC end do not have CTS detection. When the Bluetooth communication rate is lower
than the serial port rate, for reliable transparent transmission, please use flow control . It is recommended to
use the software SecureCRT.