BLE-SER
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6. Functional description
6.1. Smart pairing
When the BLE-SER module is in master-slave mode, it can be paired with the designated CH9140/CH9143
without inputting MAC address through AT command. After successful pairing, the two will establish a
binding relationship, and there is no need to re-pair when connecting again.
Pairing procedure:
1) The CH9140 is in master-slave mode, and the CH9140/CH9143 is in slave mode or master-slave mode;
2) Both sides need to complete power-up within 3s to establish a pairing;
3) The indicator LED flashes 3 times and then keeps on, indicating that pairing is successful.
If the user needs to re-establish the pairing, repeat the pairing process again. The difference is that the
indicator LED in step 3 will flash quickly. In this case, the pairing can be re-established by powering up the
chip or module.
6.2. Serial transparent transmission function
A UART is used for serial transparent transmission. The default setting is 115200bit/s baud rate, 8 data bits,
1 stop bit, no parity and enabled flow control. The UART receive and transmit buffers of the chip are each
1K bytes, and UART will perform BLE transmission in real time while receiving data. BLE communication
rate is related to its environment, so it is recommended to use CTS/RTS flow control to prevent buffer
overflow when BLE average RSSI is less than -70dBm. But when the communication quality is poor and the
chip UART receiving speed is greater than 2KB/s, it is recommended to use CTS/RTS flow control to
prevent buffer overflow.
6.3. LED function
List of LED status description
