Crc

Overview

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

Macros
#define	CRC_DRIVER_USE_CRC16_CCIT_FALSE_AS_DEFAULT   1
	Default configuration structure filled by CRC_GetDefaultConfig(). More...

Enumerations
enum	crc_bits_t {   kCrcBits16 = 0U,   kCrcBits32 = 1U }
	CRC bit width. More...
enum	crc_result_t {   kCrcFinalChecksum = 0U,   kCrcIntermediateChecksum = 1U }
	CRC result type. More...

Functions
void	CRC_Init (CRC_Type *base, const crc_config_t *config)
	Enables and configures the CRC peripheral module. More...
static void	CRC_Deinit (CRC_Type *base)
	Disables the CRC peripheral module. More...
void	CRC_GetDefaultConfig (crc_config_t *config)
	Loads default values to the CRC protocol configuration structure. More...
void	CRC_WriteData (CRC_Type *base, const uint8_t *data, size_t dataSize)
	Writes data to the CRC module. More...
uint32_t	CRC_Get32bitResult (CRC_Type *base)
	Reads the 32-bit checksum from the CRC module. More...
uint16_t	CRC_Get16bitResult (CRC_Type *base)
	Reads a 16-bit checksum from the CRC module. More...

Driver version
#define	FSL_CRC_DRIVER_VERSION   (MAKE_VERSION(2, 0, 1))
	CRC driver version. More...

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Data Structure Documentation

struct crc_config_t

This structure holds the configuration for the CRC protocol.

Data Fields
uint32_t	polynomial
	CRC Polynomial, MSBit first. More...
uint32_t	seed
	Starting checksum value.
bool	reflectIn
	Reflect bits on input. More...
bool	reflectOut
	Reflect bits on output. More...
bool	complementChecksum
	True if the result shall be complement of the actual checksum. More...
crc_bits_t	crcBits
	Selects 16- or 32- bit CRC protocol. More...
crc_result_t	crcResult
	Selects final or intermediate checksum return from CRC_Get16bitResult() or CRC_Get32bitResult()

Field Documentation

uint32_t crc_config_t::polynomial

Example polynomial: 0x1021 = 1_0000_0010_0001 = x^12+x^5+1

bool crc_config_t::reflectIn

bool crc_config_t::reflectOut

bool crc_config_t::complementChecksum

crc_bits_t crc_config_t::crcBits

Macro Definition Documentation

#define FSL_CRC_DRIVER_VERSION   (MAKE_VERSION(2, 0, 1))

Version 2.0.1.

Current version: 2.0.1

Change log:

• Version 2.0.1
  • move DATA and DATALL macro definition from header file to source file

#define CRC_DRIVER_USE_CRC16_CCIT_FALSE_AS_DEFAULT   1

Use CRC16-CCIT-FALSE as defeault.

Enumeration Type Documentation

enum crc_bits_t

Enumerator
kCrcBits16	Generate 16-bit CRC code.
kCrcBits32	Generate 32-bit CRC code.

enum crc_result_t

Enumerator
kCrcFinalChecksum	CRC data register read value is the final checksum. Reflect out and final xor protocol features are applied.
kCrcIntermediateChecksum	CRC data register read value is intermediate checksum (raw value). Reflect out and final xor protocol feature are not applied. Intermediate checksum can be used as a seed for CRC_Init() to continue adding data to this checksum.

Function Documentation

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

This function enables the clock gate in the SIM module for the CRC peripheral. It also 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_Deinit ( CRC_Type *  base )

inlinestatic

This function disables the clock gate in the SIM module for the CRC peripheral.

Parameters

base	CRC peripheral address.

void CRC_GetDefaultConfig

(

crc_config_t *

config

)

Loads default values to the CRC protocol configuration structure. The default values are as follows.

*   config->polynomial = 0x1021;
*   config->seed = 0xFFFF;
*   config->reflectIn = false;
*   config->reflectOut = false;
*   config->complementChecksum = false;
*   config->crcBits = kCrcBits16;
*   config->crcResult = kCrcFinalChecksum;
* 

Parameters

config

CRC protocol configuration structure.

void CRC_WriteData	(	CRC_Type *	base,
		const uint8_t *	data,
		size_t	dataSize
	)

Writes input data buffer bytes to the CRC data register. The configured type of transpose is applied.

Parameters

base	CRC peripheral address.
data	Input data stream, MSByte in data[0].
dataSize	Size in bytes of the input data buffer.

uint32_t CRC_Get32bitResult

(

CRC_Type *

base

)

Reads the CRC data register (either an intermediate or the final checksum). The configured type of transpose and complement is applied.

Parameters

base	CRC peripheral address.

Returns

An intermediate or the final 32-bit checksum, after configured transpose and complement operations.

uint16_t CRC_Get16bitResult

(

CRC_Type *

base

)

Reads the CRC data register (either an intermediate or the final checksum). The configured type of transpose and complement is applied.

Parameters

base	CRC peripheral address.

Returns

An intermediate or the final 16-bit checksum, after configured transpose and complement operations.