# crc

**Repository Path**: Createtree/crc

## Basic Information

- **Project Name**: crc
- **Description**: 基于C语言的CRC库
- **Primary Language**: Unknown
- **License**: Apache-2.0
- **Default Branch**: master
- **Homepage**: None
- **GVP Project**: No

## Statistics

- **Stars**: 0
- **Forks**: 0
- **Created**: 2024-03-15
- **Last Updated**: 2024-03-15

## Categories & Tags

**Categories**: Uncategorized

**Tags**: None

## README

## CRC

> 基于C语言的CRC算法库

### Feature

- 仅一个函数接口
- 实现并测试了常用CRC参数模型，详见下表：

| CRC算法名称        | 多项式公式                                                                                              | 宽度 | 多项式   | 初始值   | 结果异或值 | 输入反转 | 输出反转 |
| ------------------ | ------------------------------------------------------------------------------------------------------- | ---- | -------- | -------- | ---------- | -------- | -------- |
| CRC-4/ITU          | x^4 + x + 1                                                                                             | 4    | 03       | 00       | 00         | true     | true     |
| CRC-5/EPC          | x^5 + x^3  + 1                                                                                          | 5    | 09       | 09       | 00         | false    | false    |
| CRC-5/ITU          | x^5 + x^4  + x^2  + 1                                                                                   | 5    | 15       | 00       | 00         | true     | true     |
| CRC-5/USB          | x^5 + x^2  + 1                                                                                          | 5    | 05       | 1F       | 1F         | true     | true     |
| CRC-6/ITU          | x^6 + x + 1                                                                                             | 6    | 03       | 00       | 00         | true     | true     |
| CRC-7/MMC          | x^7 + x^3  + 1                                                                                          | 7    | 09       | 00       | 00         | false    | false    |
| CRC-8              | x^8 + x^2  + x + 1                                                                                      | 8    | 07       | 00       | 00         | false    | false    |
| CRC-8/ITU          | x^8 + x^2  + x + 1                                                                                      | 8    | 07       | 00       | 55         | false    | false    |
| CRC-8/ROHC         | x^8 + x^2  + x + 1                                                                                      | 8    | 07       | FF       | 00         | true     | true     |
| CRC-8/MAXIM        | x^8 + x^5  + x^4  + 1                                                                                   | 8    | 31       | 00       | 00         | true     | true     |
| CRC-16/IBM         | x^16 + x^15  + x^2  + 1                                                                                 | 16   | 8005     | 0000     | 0000       | true     | true     |
| CRC-16/MAXIM       | x^16 + x^15  + x^2  + 1                                                                                 | 16   | 8005     | 0000     | FFFF       | true     | true     |
| CRC-16/USB         | x^16 + x^15  + x^2  + 1                                                                                 | 16   | 8005     | FFFF     | FFFF       | true     | true     |
| CRC-16/MODBUS      | x^16 + x^15  + x^2  + 1                                                                                 | 16   | 8005     | FFFF     | 0000       | true     | true     |
| CRC-16/CCITT       | x^16 + x^12  + x^5  + 1                                                                                | 16   | 1021     | 0000     | 0000       | true     | true     |
| CRC-16/CCITT-FALSE | x^16 + x^12  + x^5  + 1                                                                                | 16   | 1021     | FFFF     | 0000       | false    | false    |
| CRC-16/X25         | x^16 + x^12  + x^5  + 1                                                                                 | 16   | 1021     | FFFF     | FFFF       | true     | true     |
| CRC-16/XMODEM      | x^16 + x^12  + x^5  + 1                                                                                 | 16   | 1021     | 0000     | 0000       | false    | false    |
| CRC-16/DNP         | x^16 + x^13  + x^12  + x^11  + x^10  + x^8  + x^6  + x^5  + x^2  + 1                                    | 16   | 3D65     | 0000     | FFFF       | true     | true     |
| CRC-32             | x^32 + x^26  + x^23  + x^22  + x^16  + x^12  + x^11  + x^10  + x^8  + x^7  + x^5  + x^4  + x^2  + x + 1 | 32   | 04C11DB7 | FFFFFFFF | FFFFFFFF   | true     | true     |
| CRC-32/MPEG-2      | x^32 + x^26  + x^23  + x^22  + x^16  + x^12  + x^11  + x^10  + x^8  + x^7  + x^5  + x^4  + x^2  + x + 1 | 32   | 04C11DB7 | FFFFFFFF | 00000000   | false    | false    |

### Usage

使用本库提供的模板

```C
#include "crc.h"
#include <stdio.h>

int main(void)
{
    uint8_t test[] = {0,1,2,3,4,5,6,7,8,9,0x0A,0x0B,0x0C,0x0D,0x0E,0x0F};
    uint32_t crc_result = CRC_CALC(&CRC_CFG_32_MPEG2, test, sizeof(test));
    printf("result:%08X\n\r", crc_result);
}
```

使用自定义模板

```C
#include "crc.h"
#include <stdio.h>
// [1] create your crc config //
const crc_config_t mycrc =
{  
  .initialValue = InitialValue,
  .polynomial = Polynomial,
  .xorOutput = XorOutput,
  .width = Width,
  .invertInput = InvertInput,
  .invertOutput = InvertOutput
};
int main(void)
{
    uint8_t test[] = {0,1,2,3,4,5,6,7,8,9,0x0A,0x0B,0x0C,0x0D,0x0E,0x0F};
    // [2] calculate crc use your config //
    uint32_t crc_result = crc_calculate(&mycrc, mycrc.initialValue, sizeof(test));
    printf("result:%08X\n\r", crc_result);
}
```


### Update Logs

2024.3.15 v0.1

> - 创建文件
> - 实现了crc_calculate接口