bin.crc16()
bin.crc16(data,len) → numberModbus CRC16 checksum function
Generate a crc16 checksum from a chunk of data
Arguments
| Name | Type | Required | Default | Description |
|---|---|---|---|---|
| data | string | yes | — | |
| len | number | optional | data.length |
Returns
number
Checksum Value
Example
serial.init(2,9600);
let modbusFrame = bin.alloc(8);
modbusFrame.write("U8",3); // Slave Address
modbusFrame.write("U8",0x06); // 0x06 Function Code (Write Single Register)
modbusFrame.write("U16BA",0); // Register
modbusFrame.write("U16BA",1234); // Value
let crc = modbus.crc16(modbusFrame,6); // Generate the CRC from the first 6 bytes of our payload
modbusFrame.write("U16BA,crc); // write the CRC to the end of our message
serial.tx(2,modbusFrame); // Send the frame over the RS485 port.