0
点赞
收藏
分享

微信扫一扫

convert CAN frame

前言

最近了解了一些socket can的知识点,本文主要介绍如何将数据转换为CAN报文,前提是已经确定CAN的传输协议。

本文使用的CAN报文共有22条,这些报文共用一个can id,每条报文使用序号标志;

报文协议

convert CAN frame_原始数据

转换数据程序

convert CAN frame_2d_02

convert CAN frame_数据_03

char* convert_buf(vector<Point>& probp, vector<Distance>& pdist, vector<int>& plabel)
{
//convert-can-frame.
char buffer[22][8] = { 0 };
for (int i = 0; i < 22; i++)
{
double lat_factor = 0.1;
double long_factor = 0.2;

unsigned int lat01 = static_cast<unsigned int>(pdist[3 * i].x_dis / lat_factor);//unit-2dm-8bits.
unsigned int long01 = static_cast<unsigned int>(pdist[3 * i].y_dis / long_factor);//unit-2dm-9bits.
int label01 = plabel[i*3];

if (i == 21)
{
buffer[i][0] = (((i+1) & 0xFF) << 3) + ((long01 & 0x1FF) >> 6);
buffer[i][1] = ((long01 & 0x1FF) << 2) + ((lat01 & 0xFF) >> 6);
buffer[i][2] = ((lat01 & 0xFF) << 2) + (label01 & 0x03);
break;
}

unsigned int lat02 = static_cast<unsigned int>(pdist[3 * i + 1].x_dis / lat_factor);//unit-2dm-8bits.
unsigned int long02 = static_cast<unsigned int>(pdist[3 * i + 1].y_dis / long_factor);//unit-2dm-9bits.
int label02 = plabel[3 * i + 1];

unsigned int lat03 = static_cast<unsigned int>(pdist[3 * i + 2].x_dis / lat_factor);//unit-2dm-8bits.
unsigned int long03 = static_cast<unsigned int>(pdist[3 * i + 2].y_dis / long_factor);//unit-2dm-9bits.
int label03 = plabel[3 * i + 2];

std::cout << "long01 --- " << long01 << "-- long02 --- " << long02 << "--- long03 --- " << long03 << std::endl;
buffer[i][0] = (((i + 1) & 0xFF) << 3) + ((long01 & 0x1FF) >> 6);
buffer[i][1] = ((long01 & 0x1FF) << 2) + ((lat01 & 0xFF) >> 6);
buffer[i][2] = ((lat01 & 0xFF) << 2) + (label01 & 0x03);
buffer[i][3] = ((long02 & 0x1FF) >> 1);
buffer[i][4] = ((long02 & 0x1FF) << 7) + ((lat02 & 0xFF) >> 1);
buffer[i][5] = ((lat02 & 0xFF) << 7) + ((label02 & 0x03) << 5) + ((long03 & 0x1FF) >> 4);
buffer[i][6] = ((long03 & 0x1FF) << 4) + ((lat03 & 0xFF) >> 4);
buffer[i][7] = ((lat03 & 0xFF) << 4) + ((label03 & 0x03) << 2);

printf("buffer[0]: --- %x\n", (byte)buffer[i][0]);
printf("buffer[1]: --- %x\n", (byte)buffer[i][1]);
printf("buffer[2]: --- %x\n", (byte)buffer[i][2]);
printf("buffer[3]: --- %x\n", (byte)buffer[i][3]);
printf("buffer[4]: --- %x\n", (byte)buffer[i][4]);
printf("buffer[5]: --- %x\n", (byte)buffer[i][5]);
printf("buffer[6]: --- %x\n", (byte)buffer[i][6]);
printf("buffer[7]: --- %x\n", (byte)buffer[i][7]);

}
cout << "sizeof(buffer): " << sizeof(buffer) << " Byte..." << endl;
return buffer[0];

}

View Code

注意

1.如何确定CAN协议的格式,特别是信号的范围、精度以及比特位数;

2.浮点型数据如何变换为可以进行逻辑运算和位移操作的数据类型;

3.如何按照报文格式得到每个字节的内容,特别是位移操作;

4.如何将报文内容正确输出方便查看;

5.原始数据可能越界,应该在转换为报文数据之前对原始数据进行越界处理;

6.转换为CAN报文过程中的各个操作符号的优先级;

举报

相关推荐

0 条评论