lua脚本CRC16校验

--calculate CRC16校验
--@data : t, data to be verified
--@n    : number of verified
--@return : check result
function add_crc16(start, n, data)local carry_flag, a = 0local result = 0xfffflocal i = startwhile(true)doresult = result ~ data[i]for j = 0, 7doa = resultcarry_flag = a & 0x0001result = result >> 1if carry_flag == 1thenresult = result ~ 0xa001endendi = i + 1if i == start + nthenbreakendendreturn result
end

lua脚本串口发送与CRC16校验使用方法

function UartSendBuf()local BUF= {}--数据缓冲区local send_crc16 = 0local cmd_head   = 0x5A --帧头local cmd_end    = 0xA5 --帧尾BUF[0] = cmd_headBUF[1] = 0x01BUF[2] = 0x02BUF[3] = 0x03BUF[4] = 0x03send_crc16 = add_crc16(1, 4, BUF)--计算BUF[1]至BUF[4]CRC校验值--send_crc16 = add_crc16(0, 4, BUF)--计算BUF[0]至BUF[4]CRC校验值BUF[5] = (send_crc16 >> 8) & 0xFFBUF[6] = (send_crc16 >> 0) & 0xFFBUF[7] = cmd_enduart_send_data(BUF)
end

lua脚本串口接收与CRC16校验使用方法

local buff         = {}--数据缓冲区
local cmd_length   = 0 --帧长度
local cmd_head_tag = 0
local cmd_end_tag  = 0 --帧尾标识-- 系统函数: 串口接收函数
function on_uart_recv_data(packet)local cmd_head = 0xA5  --帧头local cmd_end  = 0x5A  --帧尾local recv_packet_size = (#(packet))local check16          = 0for i = 0, recv_packet_size doif packet[i] == cmd_head and cmd_head_tag == 0thencmd_head_tag = 1endif cmd_head_tag == 1thenbuff[cmd_length] = packet[i]cmd_length = cmd_length + 1cmd_end_tag = (cmd_end_tag << 8) | (packet[i])if (cmd_end_tag & cmd_end)== cmd_endthencheck16 = ((buff[cmd_length - 3] << 8) | buff[cmd_length - 2]) & 0xFFFF print('CODE= '..string.format('%04X', check16))print('check16_is = '..string.format('%04X', add_crc16(0, cmd_length - 3, buff)))  --打印包含帧头校验值，不含校验位、帧尾--print('check16_is = '..string.format('%04X', add_crc16(1, cmd_length - 3, buff)))  --打印不包含帧头、校验位、帧尾、校验值。if check16 == add_crc16(0, cmd_length - 3, buff) --包含帧头校验--if check16 == add_crc16(1, cmd_length - 3, buff) --不包含帧头校验then--your code start--Processmessage(buff)--your code start end	buff         = {}cmd_length   = 0cmd_end_tag  = 0cmd_head_tag = 0	endendendend
end