CRC: Cyclic Redundancy Check Driver

Overview

The MCUXpresso SDK provides a peripheral driver for the Cyclic Redundancy Check (CRC) module of MCUXpresso SDK devices.

The cyclic redundancy check (CRC) module generates 16/32-bit CRC code for error detection. The CRC module also provides a programmable polynomial, seed, and other parameters required to implement a 16-bit or 32-bit CRC standard.

Data Structures
struct	crc_config_t
	CRC protocol configuration. More...

Macros
#define	FSL_CRC_DRIVER_VERSION   (MAKE_VERSION(2, 0, 0))
	CRC driver version 2.0.0. More...

Enumerations
enum	crc_type_t {   kCRC_Crc16 = CRC_CONTROL_CRCMOD(0),   kCRC_Crc32 = CRC_CONTROL_CRCMOD(1) }
	CRC type. More...
enum	crc_endian_t {   kCRC_MsbFirst = CRC_CONTROL_CRCINV(0),   kCRC_LsbFirst = CRC_CONTROL_CRCINV(1) }
	CRC INV selection. More...

Functions
void	CRC_Init (CRC_Type *base)
	Enables the CRC peripheral module. More...
void	CRC_Deinit (CRC_Type *base)
	Disables the CRC peripheral module. More...
void	CRC_GetDefaultConfig (crc_config_t *config)
	Provide default CRC protocol configuration. More...
void	CRC_SetConfig (CRC_Type *base, const crc_config_t *config)
	Configures the CRC peripheral module. More...
static void	CRC_SetSeed (CRC_Type *base, uint32_t crcPreload)
	Set the CRC seed value. More...
void	CRC_WriteData (CRC_Type *base, const uint8_t *buffer, uint32_t len)
	Set CRC type of transpose of write data. More...
static uint32_t	CRC_GetResult (CRC_Type *base)
	Reads the checksum from the CRC module. More...

---

Data Structure Documentation

struct crc_config_t

This structure holds the configuration for the CRC protocol.

Data Fields
bool	crcEnable: 1
	Block Enable or Disable. More...
crc_type_t	crcMode
	Select CRC protocol. More...
crc_endian_t	crcEndian
	Select MSB or ILSB first data processing. More...

Field Documentation

bool crc_config_t::crcEnable

crc_type_t crc_config_t::crcMode

crc_endian_t crc_config_t::crcEndian

Macro Definition Documentation

#define FSL_CRC_DRIVER_VERSION   (MAKE_VERSION(2, 0, 0))

Enumeration Type Documentation

enum crc_type_t

CRC-16: poly:0x1021 CRC-32: poly:0x04C11DB7

Enumerator
kCRC_Crc16	CRC-16 protocol.
kCRC_Crc32	CRC-32 protocol.

enum crc_endian_t

Enumerator
kCRC_MsbFirst	MSB, in this mode, refIn = false, refOut = false.
kCRC_LsbFirst	LSB, in this mode, refIn = true, refOut = true.

Function Documentation

void CRC_Init

(

CRC_Type *

base

)

This function enables the clock gate for the CRC peripheral.

Parameters

base	CRC peripheral address.

void CRC_Deinit

(

CRC_Type *

base

)

This function disables the clock gate for the CRC peripheral.

Parameters

base	CRC peripheral address.

void CRC_GetDefaultConfig

(

crc_config_t *

config

)

The purpose of this API is to initialize the configuration structure to default value for CRC_SetConfig to use. Provides the configuration of commonly used CRC protocols. The default configuration is:

    config->enable = true;
    config->crcMode = kCRC_Crc16;
    config->crcEndian = kCRC_LsbFirst;
* 

This is an example:

       crc_config_t crc16Config;
       //Load CRC-16 protocol configuration.
       CRC_GetDefaultConfig(&crc16Config);
       CRC_SetConfig(CRC, crc16Config);
* 

Parameters

config

CRC protocol configuration structure.

void CRC_SetConfig	(	CRC_Type *	base,
		const crc_config_t *	config
	)

This function configures the CRC module and starts a checksum computation by writing the seed.

Parameters

base	CRC peripheral address.
config	CRC module configuration structure.

static void CRC_SetSeed ( CRC_Type *  base, uint32_t  crcPreload  )

inlinestatic

This function is help to write a 16/32 bit CRC seed value.

Parameters

base	CRC peripheral address.
crcPreload	The value of seed.

void CRC_WriteData	(	CRC_Type *	base,
		const uint8_t *	buffer,
		uint32_t	len
	)

This function writes data to CRC.

Parameters

base	CRC peripheral address.
buffer	data message to be checked.
len	length of buffer.

static uint32_t CRC_GetResult ( CRC_Type *  base )

inlinestatic

Reads the CRC data register (either an intermediate or the final checksum).

Parameters

base	CRC peripheral address.

Returns

An intermediate or the final checksum, after transpose and complement operations configured.