ESP32 和 C# 的 CRC16

CRC-16 有很多种,这里使用的是CRC-16/CCITT-FALSE。可以用这个在线工具进行验证(注意下图是16进制数值):

https://crccalc.com/

1.

static unsigned short crc16(const unsigned char *buf, unsigned long count)
{
  unsigned short crc = 0xFFFF;
  int i;

  while(count--) {
    crc = crc ^ *buf++ << 8;

    for (i=0; i<8; i++) {
      if (crc & 0x8000) crc = crc << 1 ^ 0x1021;
      else crc = crc << 1;
    }
  }
  return crc;
}

void setup() {
        Serial.begin(115200);
}

void loop() {
        byte data[11]={0x11,0x22,0x33,0x44,0x55,0x66,0x77,0x88,0x99,0x00,0x11};
        Serial.println(crc16(data,11),HEX);
        delay(10000);
}

2.C# 代码

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Runtime.InteropServices;

namespace CRC16Test
{
    class Program
    {


        static void Main(string[] args)
        {
            byte[] data = new byte[] { 0x11, 0x22, 0x33, 0x44, 0x55, 0x66, 0x77, 0x88, 0x99, 0x00,0x11};
            /*           for (int i = 0; i < 10; i++)
                       {
                           data[i] = (byte)(i % 256);
                       }
           */
            string hex = Crc16Ccitt(data).ToString("x2");
            Console.WriteLine(hex);

            Console.Write("Press any key to continue . . . ");
            Console.ReadKey(true);
        }

        //
        // CRC-16/CCITT-FALSE
        // https://crccalc.com/
        //
        public static ushort Crc16Ccitt(byte[] bytes)
        {
            const ushort poly = 0x1021;
            ushort[] table = new ushort[256];
            ushort initialValue = 0xffff;
            ushort temp, a;
            ushort crc = initialValue;
            for (int i = 0; i < table.Length; ++i)
            {
                temp = 0;
                a = (ushort)(i << 8);
                for (int j = 0; j < 8; ++j)
                {
                    if (((temp ^ a) & 0x8000) != 0)
                        temp = (ushort)((temp << 1) ^ poly);
                    else
                        temp <<= 1;
                    a <<= 1;
                }
                table[i] = temp;
            }
            for (int i = 0; i < bytes.Length; ++i)
            {
                crc = (ushort)((crc << 8) ^ table[((crc >> 8) ^ (0xff & bytes[i]))]);
            }
            return crc;
        }

    }
}

发表评论

您的电子邮箱地址不会被公开。 必填项已用*标注