## Introduction

Data may be subject to errors during the transmission process due to various reasons. In order to control errors in the transmission process, communication systems often adopt data verification to ensure the integrity of data.

Common data verification algorithms include sum check, parity check, exclusive OR check, Longitudinal Redundancy Check (LRC), and Cyclic Redundancy Check (CRC). The code for commonly used verification algorithms is also provided here.

## Interface

```c
uint8_t check_sum(uint8_t* data, uint32_t len);       // Sum check algorithm
uint8_t check_parity(uint8_t* data, uint32_t len);    // Parity check
uint8_t check_lrc(uint8_t* data, uint32_t len);       // Longitudinal Redundancy Check
uint8_t check_xor(uint8_t* data, uint32_t len);       // Exclusive OR check
```
The usage methods of these several verification algorithms are the same. They all take the data address and data length as input parameters and return the calculated verification value.