CRC Interface

Interface for cyclic redundancy checking. More...

Data Structures
struct	crc_cfg_t
struct	crc_snoop_cfg_t
struct	crc_api_t
struct	crc_instance_t

Typedefs
typedef void	crc_ctrl_t

Enumerations
enum	crc_polynomial_t {   CRC_POLYNOMIAL_CRC_8 = 1, CRC_POLYNOMIAL_CRC_16, CRC_POLYNOMIAL_CRC_CCITT, CRC_POLYNOMIAL_CRC_32,   CRC_POLYNOMIAL_CRC_32C }
enum	crc_bit_order_t { CRC_BIT_ORDER_LMS_LSB = 0, CRC_BIT_ORDER_LMS_MSB }
enum	crc_snoop_direction_t { CRC_SNOOP_DIRECTION_RECEIVE = 0, CRC_SNOOP_DIRECTION_TRANSMIT }

Detailed Description

Interface for cyclic redundancy checking.

Summary

The CRC (Cyclic Redundancy Check) calculator generates CRC codes using five different polynomials including 8 bit, 16 bit, and 32 bit variations. Calculation can be performed by sending data to the block using the CPU or by snooping on read or write activity on one of 10 SCI channels.

Related SSP architecture topics:

• SSP Interfaces
• SSP Predefined Layers
• Using SSP Modules

CRC Interface description: CRC Driver

Typedef Documentation

crc_ctrl_t

typedef void crc_ctrl_t

CRC control block. Allocate an instance specific control block to pass into the CRC API calls.

Implemented as

• crc_instance_ctrl_t

Enumeration Type Documentation

crc_bit_order_t

enum crc_bit_order_t

CRC Calculation Switching (LMS)

Enumerator
CRC_BIT_ORDER_LMS_LSB	Generates CRC for LSB first communication.
CRC_BIT_ORDER_LMS_MSB	Generates CRC for MSB first communication.

crc_polynomial_t

enum crc_polynomial_t

CRC Generating Polynomial Switching (GPS).

Enumerator
CRC_POLYNOMIAL_CRC_8	8-bit CRC-8 (X^8 + X^2 + X + 1)
CRC_POLYNOMIAL_CRC_16	16-bit CRC-16 (X^16 + X^15 + X^2 + 1)
CRC_POLYNOMIAL_CRC_CCITT	16-bit CRC-CCITT (X^16 + X^12 + X^5 + 1)
CRC_POLYNOMIAL_CRC_32	32-bit 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)
CRC_POLYNOMIAL_CRC_32C	32-bit CRC-32C (X^32 + X^28 + X^27 + X^26 + X^25 + X^23 + X^22 + X^20 + X^19 + X^18 + X^14 + X^13 + X^11 + X^10 + X^9 + X^8 + X^6 + 1)

crc_snoop_direction_t

enum crc_snoop_direction_t

Snoop-On-Write/Read Switch (CRCSWR)

Enumerator
CRC_SNOOP_DIRECTION_RECEIVE	Snoop-on-read.
CRC_SNOOP_DIRECTION_TRANSMIT	Snoop-on-write.