The baud rate isan important parameter when setting the wireless module. This article explainshow to set the baud rate correctly.
Firstly,introduce the baud rate briefly. The baud rate indicates the number of symbolsymbols transmitted per second. It is an index to measure the data transmissionrate. It is expressed by the number of times the carrier modulation statechanges in a unit time. MCU or computer speed in serial communication. Refersto the change in the unit time after the signal is modulated, that is, thenumber of times the carrier parameter changes in the unit time. For example,the data transmission rate is 240b / s, and each character format contains 10bits (1 start bit, 1 Stop bit, 8 effective data bits). At this time, the baudrate is 240 baud (baud), and the bit rate (effective data bit transmissionrate) is 240 * 10 = 2400 bps (bits per second). (But generally the modulationrate is greater than the baud rate, such as Manchester encoding). The baud ratecan be commonly understood as how many symbols of data a device sends (orreceives) in one second. It is a measure of the symbol transmission rate. 1baud means that one symbol symbol is transmitted per second (through differentmodulation methods, multiple bits of information can be carried on one symbolsymbol). One bit per second It means 1 bit per second. The unit"Baud" itself already represents the number of modulations persecond, and it is a common mistake to use "Baud per second" as aunit.
After understanding the basic concept ofbaud rate, we will know how to set the baud rate. In fact, setting the baudrate indicates setting a communication parameter, and the set value should bebased on actual requirements.
Take thewireless LoRa610 wireless module as an example, our company provides two settingmethods, one is through PC software, and the other is to modify parametersthrough serial port commands. The following is the interface of the PCsoftware. With this PC software, almost all parameters can be set. Theinterface is as follows.
When settingthrough serial command, you need to input the command set by our company. ForLoRa610 module, the command to modify the baud rate of the serial port is 03,the parameter setting command, the parameters are 14 bytes, the order is asfollows: send and receive channel-working frequency band-air communicationrate-transmit power-serial baud rate-serial data —Serial stop bit—Serial check bit—NET ID—NODE ID
Theconfiguration instructions are: AA FA 03 XX XX XX XX XX XX XX XX XX XX XX XX XXXX
Returninstruction: "OK \ r \ n" or "ERROR \ r \ n".
The above is toset the baud rate. I hope to help you.