RF-Star EFR32BG22, Manual

Page: 80 / 94

EFR32BG22
www.szrfstar.com V1.6 - Jun., 2022
Shenzhen RF-star Technology Co., Ltd.
Page 79 of 93
8 MCU Reference Code (Transparent Transmission)
The serial port between the module and the MCU uses hardware flow control IO ports (CTS and RTS) to send and
receive notifications and control.
These two IOs are always at a high level and will be triggered when pull low.
When the module can receive data, the module will pull the RTS signal low (CTS for the MCU) to notify the MCU that it
can send data.
When MCU can receive data, MCU should pull the RTS signal low (CTS for the module) to inform the module that it can
send data.
The demo code is as follows (for reference only):
void main(void)
{
//Wait for the BLE module to start successfully
while(!memcmp(rx_ble_mode_data(),"DEVICE_START\r\n",strlen("DEVICE_START\r\n")));
//Enable RTS, that is, MCU can receive date from BLE module
set_rts_enable();
While(1){
//Aquire whether the CTS status is at a low level
If(get_cts_state()==0){
// Send test data to BLE module
mcu_send_to_ble_string("Test data.\r\n");
}
// Processing the data obtained by MCU
mcu_data_process(mcu_uart_read_data());
}
}