CAT2 Peripheral Driver Library
Functions
Cyclic redundancy code (CRC)
Crypto (Cryptography) » Functions

Functions

cy_en_crypto_status_t Cy_Crypto_Crc_CalcInit (CRYPTO_Type *base, uint32_t width, uint32_t polynomial, bool dataReverse, uint8_t dataXor, bool remReverse, uint32_t remXor, uint32_t lfsrInitState, cy_stc_crypto_crc_context_t *crcContext)
 This function initializes the CRC (Cyclic Redundancy Check) calculation. More...
 
cy_en_crypto_status_t Cy_Crypto_Crc_Calc (CRYPTO_Type *base, uint32_t *crc, void const *data, uint32_t dataSize, cy_stc_crypto_crc_context_t *crcContext)
 This function performs the CRC calculation on a message. More...
 
cy_en_crypto_status_t Cy_Crypto_Crc_CalcPartial (CRYPTO_Type *base, void const *data, uint32_t dataSize, cy_stc_crypto_crc_context_t *crcContext)
 This function performs the CRC calculation on partial data which is part of a complete message. More...
 
cy_en_crypto_status_t Cy_Crypto_Crc_CalcFinish (CRYPTO_Type *base, uint32_t *crc, cy_stc_crypto_crc_context_t *crcContext)
 This function completes the CRC calculation for message provided with Cy_Crypto_Crc_CalcPartial() function. More...
 
cy_en_crypto_status_t Cy_Crypto_Crc_CalcFree (CRYPTO_Type *base, cy_stc_crypto_crc_context_t *crcContext)
 This function clears the CRC context. More...
 

Detailed Description

Function Documentation

◆ Cy_Crypto_Crc_CalcInit()

cy_en_crypto_status_t Cy_Crypto_Crc_CalcInit ( CRYPTO_Type *  base,
uint32_t  width,
uint32_t  polynomial,
bool  dataReverse,
uint8_t  dataXor,
bool  remReverse,
uint32_t  remXor,
uint32_t  lfsrInitState,
cy_stc_crypto_crc_context_t *  crcContext 
)

This function initializes the CRC (Cyclic Redundancy Check) calculation.

The following table lists known polynomials with different parameters and their calculated CRCs from the string "123456789":

Name Width Poly Init Data Rev Data XOR Rem Rev Rem XOR Expected CRC
CRC-3 / ROHC 3 0x3 0x7 1 0 1 0x0 0x6
CRC-4 / ITU 4 0x3 0x0 1 0 1 0x0 0x7
CRC-5 / EPC 5 0x9 0x9 0 0 0 0x0 0x0
CRC-5 / ITU 5 0x15 0x0 1 0 1 0x0 0x7
CRC-5 / USB 5 0x5 0x1F 1 0 1 0x1F 0x19
CRC-6 / CDMA2000-A 6 0x27 0x3F 0 0 0 0x0 0xD
CRC-6 / CDMA2000-B 6 0x7 0x3F 0 0 0 0x0 0x3B
CRC-6 / DARC 6 0x19 0x0 1 0 1 0x0 0x26
CRC-6 / ITU 6 0x3 0x0 1 0 1 0x0 0x6
CRC-7 7 0x9 0x0 0 0 0 0x0 0x75
CRC-7 / ROHC 7 0x4F 0x7F 1 0 1 0x0 0x53
CRC-8 8 0x7 0x0 0 0 0 0x0 0xF4
CRC-8 / CDMA2000 8 0x9B 0xFF 0 0 0 0x0 0xDA
CRC-8 / DARC 8 0x39 0x0 1 0 1 0x0 0x15
CRC-8 / DVB-S2 8 0xD5 0x0 0 0 0 0x0 0xBC
CRC-8 / EBU 8 0x1D 0xFF 1 0 1 0x0 0x97
CRC-8 / I-CODE 8 0x1D 0xFD 0 0 0 0x0 0x7E
CRC-8 / ITU 8 0x7 0x0 0 0 0 0x55 0xA1
CRC-8 / MAXIM 8 0x31 0x0 1 0 1 0x0 0xA1
CRC-8 / ROHC 8 0x7 0xFF 1 0 1 0x0 0xD0
CRC-8 / WCDMA 8 0x9B 0x0 1 0 1 0x0 0x25
CRC-10 10 0x233 0x0 0 0 0 0x0 0x199
CRC-10 / CDMA2000 10 0x3D9 0x3FF 0 0 0 0x0 0x233
CRC-11 11 0x385 0x1A 0 0 0 0x0 0x5A3
CRC-12 / 3GPP 12 0x80F 0x0 0 0 1 0x0 0xDAF
CRC-12 / CDMA2000 12 0xF13 0xFFF 0 0 0 0x0 0xD4D
CRC-12 / DECT 12 0x80F 0x0 0 0 0 0x0 0xF5B
CRC-13 / BBC 13 0x1CF5 0x0 0 0 0 0x0 0x4FA
CRC-14 / DARC 14 0x805 0x0 1 0 1 0x0 0x82D
CRC-15 15 0x4599 0x0 0 0 0 0x0 0x59E
CRC-15 / MPT1327 15 0x6815 0x0 0 0 0 0x1 0x2566
CRC-24 24 0x0864CFB 0x00B704CE 0 0 0 0x0 0x21CF02
CRC-24 / FLEXRAY-A 24 0x05D6DCB 0x00FEDCBA 0 0 0 0x0 0x7979BD
CRC-24 / FLEXRAY-B 24 0x05D6DCB 0x00ABCDEF 0 0 0 0x0 0x1F23B8
CRC-31 / PHILIPS 31 0x4C11DB7 0x7FFFFFFF 0 0 0 0x7FFFFFFF 0xCE9E46C
CRC-16 / ARC 16 0x8005 0x0000 1 0 1 0x0000 0xBB3D
CRC-16 / AUG-CCITT 16 0x1021 0x1D0F 0 0 0 0x0000 0xE5CC
CRC-16 / BUYPASS 16 0x8005 0x0000 0 0 0 0x0000 0xFEE8
CRC-16 / CCITT-0 16 0x1021 0xFFFF 0 0 0 0x0000 0x29B1
CRC-16 / CDMA2000 16 0xC867 0xFFFF 0 0 0 0x0000 0x4C06
CRC-16 / DDS-110 16 0x8005 0x800D 0 0 0 0x0000 0x9ECF
CRC-16 / DECT-R 16 0x0589 0x0000 0 0 0 0x0001 0x007E
CRC-16 / DECT-X 16 0x0589 0x0000 0 0 0 0x0000 0x007F
CRC-16 / DNP 16 0x3D65 0x0000 1 0 1 0xFFFF 0xEA82
CRC-16 / EN-13757 16 0x3D65 0x0000 0 0 0 0xFFFF 0xC2B7
CRC-16 / GENIBUS 16 0x1021 0xFFFF 0 0 0 0xFFFF 0xD64E
CRC-16 / MAXIM 16 0x8005 0x0000 1 0 1 0xFFFF 0x44C2
CRC-16 / MCRF4XX 16 0x1021 0xFFFF 1 0 1 0x0000 0x6F91
CRC-16 / RIELLO 16 0x1021 0xB2AA 1 0 1 0x0000 0x63D0
CRC-16 / T10-DIF 16 0x8BB7 0x0000 0 0 0 0x0000 0xD0DB
CRC-16 / TELEDISK 16 0xA097 0x0000 0 0 0 0x0000 0x0FB3
CRC-16 / TMS37157 16 0x1021 0x89EC 1 0 1 0x0000 0x26B1
CRC-16 / USB 16 0x8005 0xFFFF 1 0 1 0xFFFF 0xB4C8
CRC-A 16 0x1021 0xC6C6 1 0 1 0x0000 0xBF05
CRC-16 / KERMIT 16 0x1021 0x0000 1 0 1 0x0000 0x2189
CRC-16 / MODBUS 16 0x8005 0xFFFF 1 0 1 0x0000 0x4B37
CRC-16 / X-25 16 0x1021 0xFFFF 1 0 1 0xFFFF 0x906E
CRC-16 / XMODEM 16 0x1021 0x0000 0 0 0 0x0000 0x31C3
CRC-32 32 0x04C11DB7 0xFFFFFFFF 1 0 1 0xFFFFFFFF 0xCBF43926
CRC-32 / BZIP2 32 0x04C11DB7 0xFFFFFFFF 0 0 0 0xFFFFFFFF 0xFC891918
CRC-32C 32 0x1EDC6F41 0xFFFFFFFF 1 0 1 0xFFFFFFFF 0xE3069283
CRC-32D 32 0xA833982B 0xFFFFFFFF 1 0 1 0xFFFFFFFF 0x87315576
CRC-32 / MPEG-2 32 0x04C11DB7 0xFFFFFFFF 0 0 0 0x00000000 0x0376E6E7
CRC-32 / POSIX 32 0x04C11DB7 0x00000000 0 0 0 0xFFFFFFFF 0x765E7680
CRC-32Q 32 0x814141AB 0x00000000 0 0 0 0x00000000 0x3010BF7F
CRC-32 / JAMCRC 32 0x04C11DB7 0xFFFFFFFF 1 0 1 0x00000000 0x340BC6D9
CRC-32 / XFER 32 0x000000AF 0x00000000 0 0 0 0x00000000 0xBD0BE338
Parameters
baseBase address of the Crypto block registers
widthWidth of the CRC value to be calculated in bits. Max width supported is 32-bits.
polynomialPolynomial value to be used in computing the CRC. The size of the polynomial value should be based on the width of the CRC value to be calculated.
dataReverseBit order in which each data byte is processed. 0 - MSB first; 1 - LSB first.
dataXorByte mask with which each data byte is XORed.
remReverseSpecifies whether the remainder should be bit reversed. 0 - Remainder is not reversed; 1 - Remainder is reversed.
remXorMask with which the LFSR32 register is XORed to produce a remainder.
lfsrInitStateCRC seed value used as the initial state of a 32-bit Linear Feedback Shift Register (LFSR).
crcContextPointer to the CRC context structure cy_stc_crypto_crc_context_t allocated by the user. This structure is used by the Crypto driver for the CRC calculation. Do not modify the values of this structure.
Returns
cy_en_crypto_status_t
Function Usage
/* CRC parameters for some CRC algorithms:
+---------------------+-----+------------+------------+------+------+-----+------------+------------+
| CRC algorithm Name | CRC | Polynomial | Initial | Data | Data | Rem | Remainder | Expected |
| | len | | seed | REV | XOR | REV | XOR | CRC |
| ------------------- | --- | ---------- |----------- | ---- | ---- | --- | ---------- | ---------- |
| CRC-6 / CDMA2000-A | 6 | 0x27 | 0x3F | 0 | 0 | 0 | 0x00 | 0x0D |
| CRC-6 / CDMA2000-B | 6 | 0x07 | 0x3F | 0 | 0 | 0 | 0x00 | 0x3B |
| CRC-6 / DARC | 6 | 0x19 | 0x00 | 1 | 0 | 1 | 0x00 | 0x26 |
| CRC-6 / ITU | 6 | 0x03 | 0x00 | 1 | 0 | 1 | 0x00 | 0x06 |
| CRC-8 / ITU | 8 | 0x07 | 0x00 | 0 | 0 | 0 | 0x55 | 0xA1 |
| CRC-8 / MAXIM | 8 | 0x31 | 0x00 | 1 | 0 | 1 | 0x00 | 0xA1 |
| CRC-8 / ROHC | 8 | 0x07 | 0xFF | 1 | 0 | 1 | 0x00 | 0xD0 |
| CRC-8 / WCDMA | 8 | 0x9B | 0x00 | 1 | 0 | 1 | 0x00 | 0x25 |
| CRC-16 / CCITT-0 | 16 | 0x1021 | 0xFFFF | 0 | 0 | 0 | 0x0000 | 0x29B1 |
| CRC-16 / CDMA2000 | 16 | 0xC867 | 0xFFFF | 0 | 0 | 0 | 0x0000 | 0x4C06 |
| CRC-32 | 32 | 0x04C11DB7 | 0xFFFFFFFF | 1 | 0 | 1 | 0xFFFFFFFF | 0xCBF43926 |
| CRC-32 / BZIP2 | 32 | 0x04C11DB7 | 0xFFFFFFFF | 0 | 0 | 0 | 0xFFFFFFFF | 0xFC891918 |
+---------------------+-----+------------+------------+------+------+-----+------------+------------+
*/
/* Use "CRC-16/CCITT-0" calculation */
#define CRC16CCITT_WIDTH (16u)
#define CRC16CCITT_POLYNOMIAL (0x1021)
#define CRC16CCITT_LFSR_SEED (0xffff)
#define CRC16CCITT_DATA_REVERSE (0u)
#define CRC16CCITT_DATA_XOR (0u)
#define CRC16CCITT_REM_REVERSE (0u)
#define CRC16CCITT_REM_XOR (0x0000)
uint8_t message[9] = "123456789";
uint32_t calculatedCrc = 0;
cy_stc_crypto_crc_context_t crcContext;
cy_en_crypto_status_t cryptoStatus;
/* Initialize Crypto CRC operation */
cryptoStatus = Cy_Crypto_Crc_CalcInit(
CRYPTO, /* Base address of the Crypto block registers */
CRC16CCITT_WIDTH, /* CRC width in bits*/
CRC16CCITT_POLYNOMIAL, /* CRC polynomial (specified using 32 bits) */
CRC16CCITT_DATA_REVERSE, /* Byte order for processing: 0 - MSB first; 1 - LSB first */
CRC16CCITT_DATA_XOR, /* Byte mask for XORing data */
CRC16CCITT_REM_REVERSE, /* Reverse remainder */
CRC16CCITT_REM_XOR, /* Byte mask for XORing LFSR32 register */
CRC16CCITT_LFSR_SEED, /* LFSR initial seed */
&crcContext); /* Pointer to CRC context structure */
/* ... check for errors... */
/* Calculate CRC */
cryptoStatus = Cy_Crypto_Crc_Calc(
CRYPTO, /* Base address of the Crypto block registers */
&calculatedCrc, /* Pointer to CRC result */
(void*)message, /* Pointer to message */
sizeof(message), /* Size of message */
&crcContext); /* Pointer to CRC context structure */
/* ... check for errors... */
/* Free the CRC context */
cryptoStatus = Cy_Crypto_Crc_CalcFree(
CRYPTO, /* Base address of the Crypto block registers */
&crcContext); /* Pointer to CRC context structure */
/* ... check for errors... */

◆ Cy_Crypto_Crc_Calc()

cy_en_crypto_status_t Cy_Crypto_Crc_Calc ( CRYPTO_Type *  base,
uint32_t *  crc,
void const *  data,
uint32_t  dataSize,
cy_stc_crypto_crc_context_t *  crcContext 
)

This function performs the CRC calculation on a message.

The polynomial and other CRC parameters must be set before by invoking Cy_Crypto_Crc_CalcInit().

Note
This function is to be used when the data is in one contiguous block of memory. For non-contiguous blocks of memory, use Cy_Crypto_Crc_CalcPartial() and Cy_Crypto_Crc_CalcFinish().
Parameters
baseBase address of the Crypto block registers
crcPointer to store the computed CRC value
dataPointer to the message whose CRC is being computed
dataSizeSize of the message in bytes
crcContextPointer to the CRC context structure cy_stc_crypto_crc_context_t allocated by the user. This structure is used by the Crypto driver for the CRC calculation. Do not modify the values of this structure.
Returns
cy_en_crypto_status_t
Function Usage
/* CRC parameters for some CRC algorithms:
+---------------------+-----+------------+------------+------+------+-----+------------+------------+
| CRC algorithm Name | CRC | Polynomial | Initial | Data | Data | Rem | Remainder | Expected |
| | len | | seed | REV | XOR | REV | XOR | CRC |
| ------------------- | --- | ---------- |----------- | ---- | ---- | --- | ---------- | ---------- |
| CRC-6 / CDMA2000-A | 6 | 0x27 | 0x3F | 0 | 0 | 0 | 0x00 | 0x0D |
| CRC-6 / CDMA2000-B | 6 | 0x07 | 0x3F | 0 | 0 | 0 | 0x00 | 0x3B |
| CRC-6 / DARC | 6 | 0x19 | 0x00 | 1 | 0 | 1 | 0x00 | 0x26 |
| CRC-6 / ITU | 6 | 0x03 | 0x00 | 1 | 0 | 1 | 0x00 | 0x06 |
| CRC-8 / ITU | 8 | 0x07 | 0x00 | 0 | 0 | 0 | 0x55 | 0xA1 |
| CRC-8 / MAXIM | 8 | 0x31 | 0x00 | 1 | 0 | 1 | 0x00 | 0xA1 |
| CRC-8 / ROHC | 8 | 0x07 | 0xFF | 1 | 0 | 1 | 0x00 | 0xD0 |
| CRC-8 / WCDMA | 8 | 0x9B | 0x00 | 1 | 0 | 1 | 0x00 | 0x25 |
| CRC-16 / CCITT-0 | 16 | 0x1021 | 0xFFFF | 0 | 0 | 0 | 0x0000 | 0x29B1 |
| CRC-16 / CDMA2000 | 16 | 0xC867 | 0xFFFF | 0 | 0 | 0 | 0x0000 | 0x4C06 |
| CRC-32 | 32 | 0x04C11DB7 | 0xFFFFFFFF | 1 | 0 | 1 | 0xFFFFFFFF | 0xCBF43926 |
| CRC-32 / BZIP2 | 32 | 0x04C11DB7 | 0xFFFFFFFF | 0 | 0 | 0 | 0xFFFFFFFF | 0xFC891918 |
+---------------------+-----+------------+------------+------+------+-----+------------+------------+
*/
/* Use "CRC-16/CCITT-0" calculation */
#define CRC16CCITT_WIDTH (16u)
#define CRC16CCITT_POLYNOMIAL (0x1021)
#define CRC16CCITT_LFSR_SEED (0xffff)
#define CRC16CCITT_DATA_REVERSE (0u)
#define CRC16CCITT_DATA_XOR (0u)
#define CRC16CCITT_REM_REVERSE (0u)
#define CRC16CCITT_REM_XOR (0x0000)
uint8_t message[9] = "123456789";
uint32_t calculatedCrc = 0;
cy_stc_crypto_crc_context_t crcContext;
cy_en_crypto_status_t cryptoStatus;
/* Initialize Crypto CRC operation */
cryptoStatus = Cy_Crypto_Crc_CalcInit(
CRYPTO, /* Base address of the Crypto block registers */
CRC16CCITT_WIDTH, /* CRC width in bits*/
CRC16CCITT_POLYNOMIAL, /* CRC polynomial (specified using 32 bits) */
CRC16CCITT_DATA_REVERSE, /* Byte order for processing: 0 - MSB first; 1 - LSB first */
CRC16CCITT_DATA_XOR, /* Byte mask for XORing data */
CRC16CCITT_REM_REVERSE, /* Reverse remainder */
CRC16CCITT_REM_XOR, /* Byte mask for XORing LFSR32 register */
CRC16CCITT_LFSR_SEED, /* LFSR initial seed */
&crcContext); /* Pointer to CRC context structure */
/* ... check for errors... */
/* Calculate CRC */
cryptoStatus = Cy_Crypto_Crc_Calc(
CRYPTO, /* Base address of the Crypto block registers */
&calculatedCrc, /* Pointer to CRC result */
(void*)message, /* Pointer to message */
sizeof(message), /* Size of message */
&crcContext); /* Pointer to CRC context structure */
/* ... check for errors... */
/* Free the CRC context */
cryptoStatus = Cy_Crypto_Crc_CalcFree(
CRYPTO, /* Base address of the Crypto block registers */
&crcContext); /* Pointer to CRC context structure */
/* ... check for errors... */

◆ Cy_Crypto_Crc_CalcPartial()

cy_en_crypto_status_t Cy_Crypto_Crc_CalcPartial ( CRYPTO_Type *  base,
void const *  data,
uint32_t  dataSize,
cy_stc_crypto_crc_context_t *  crcContext 
)

This function performs the CRC calculation on partial data which is part of a complete message.

The polynomial and other CRC parameters must be set before by invoking Cy_Crypto_Crc_CalcInit(). This function can be called multiple times with partial data and at the end, the user must call Cy_Crypto_Crc_CalcFinish() to get the computed CRC value.

Parameters
baseBase address of the Crypto block registers
dataPointer to the message whose CRC is being computed
dataSizeSize of the message in bytes
crcContextPointer to the CRC context structure cy_stc_crypto_crc_context_t allocated by the user. This structure is used by the Crypto driver for the CRC calculation. Do not modify the values of this structure.
Returns
cy_en_crypto_status_t
Function Usage
/* CRC parameters for some CRC algorithms:
+---------------------+-----+------------+------------+------+------+-----+------------+------------+
| CRC algorithm Name | CRC | Polynomial | Initial | Data | Data | Rem | Remainder | Expected |
| | len | | seed | REV | XOR | REV | XOR | CRC |
| ------------------- | --- | ---------- |----------- | ---- | ---- | --- | ---------- | ---------- |
| CRC-6 / CDMA2000-A | 6 | 0x27 | 0x3F | 0 | 0 | 0 | 0x00 | 0x0D |
| CRC-6 / CDMA2000-B | 6 | 0x07 | 0x3F | 0 | 0 | 0 | 0x00 | 0x3B |
| CRC-6 / DARC | 6 | 0x19 | 0x00 | 1 | 0 | 1 | 0x00 | 0x26 |
| CRC-6 / ITU | 6 | 0x03 | 0x00 | 1 | 0 | 1 | 0x00 | 0x06 |
| CRC-8 / ITU | 8 | 0x07 | 0x00 | 0 | 0 | 0 | 0x55 | 0xA1 |
| CRC-8 / MAXIM | 8 | 0x31 | 0x00 | 1 | 0 | 1 | 0x00 | 0xA1 |
| CRC-8 / ROHC | 8 | 0x07 | 0xFF | 1 | 0 | 1 | 0x00 | 0xD0 |
| CRC-8 / WCDMA | 8 | 0x9B | 0x00 | 1 | 0 | 1 | 0x00 | 0x25 |
| CRC-16 / CCITT-0 | 16 | 0x1021 | 0xFFFF | 0 | 0 | 0 | 0x0000 | 0x29B1 |
| CRC-16 / CDMA2000 | 16 | 0xC867 | 0xFFFF | 0 | 0 | 0 | 0x0000 | 0x4C06 |
| CRC-32 | 32 | 0x04C11DB7 | 0xFFFFFFFF | 1 | 0 | 1 | 0xFFFFFFFF | 0xCBF43926 |
| CRC-32 / BZIP2 | 32 | 0x04C11DB7 | 0xFFFFFFFF | 0 | 0 | 0 | 0xFFFFFFFF | 0xFC891918 |
+---------------------+-----+------------+------------+------+------+-----+------------+------------+
*/
/* Use "CRC-16/CCITT-0" calculation */
#define CRC16CCITT_WIDTH (16u)
#define CRC16CCITT_POLYNOMIAL (0x1021)
#define CRC16CCITT_LFSR_SEED (0xffff)
#define CRC16CCITT_DATA_REVERSE (0u)
#define CRC16CCITT_DATA_XOR (0u)
#define CRC16CCITT_REM_REVERSE (0u)
#define CRC16CCITT_REM_XOR (0x0000)
uint8_t message1[5] = "12345"; /* In this example, the message is processed in two parts - first 5 bytes, then 4 bytes */
uint8_t message2[4] = "6789";
uint32_t calculatedCrc = 0;
cy_stc_crypto_crc_context_t crcContext;
cy_en_crypto_status_t cryptoStatus;
/* Initialize Crypto CRC operation */
cryptoStatus = Cy_Crypto_Crc_CalcInit(
CRYPTO, /* Base address of the Crypto block registers */
CRC16CCITT_WIDTH, /* CRC width in bits */
CRC16CCITT_POLYNOMIAL, /* CRC polynomial (specified using 32 bits) */
CRC16CCITT_DATA_REVERSE, /* Byte order for processing: 0 - MSB first; 1 - LSB first */
CRC16CCITT_DATA_XOR, /* Byte mask for XORing data */
CRC16CCITT_REM_REVERSE, /* Reverse remainder */
CRC16CCITT_REM_XOR, /* Byte mask for XORing LFSR32 register */
CRC16CCITT_LFSR_SEED, /* LFSR initial seed */
&crcContext); /* Pointer to CRC context structure */
/* ... check for errors... */
/* Calculate CRC */
cryptoStatus = Cy_Crypto_Crc_CalcPartial(
CRYPTO, /* Base address of the Crypto block registers */
(void*)message1, /* Pointer to message */
sizeof(message1), /* Size of message */
&crcContext); /* Pointer to CRC context structure */
/* ... check for errors... */
/* Calculate CRC */
cryptoStatus = Cy_Crypto_Crc_CalcPartial(
CRYPTO, /* Base address of the Crypto block registers */
(void*)message2, /* Pointer to message */
sizeof(message2), /* Size of message */
&crcContext); /* Pointer to CRC context structure */
/* ... check for errors... */
/* Finish CRC */
cryptoStatus = Cy_Crypto_Crc_CalcFinish(
CRYPTO, /* Base address of the Crypto block registers */
&calculatedCrc, /* Pointer to CRC result */
&crcContext); /* Pointer to CRC context structure */
/* ... check for errors... */
/* Free the CRC context */
cryptoStatus = Cy_Crypto_Crc_CalcFree(
CRYPTO, /* Base address of the Crypto block registers */
&crcContext); /* Pointer to CRC context structure */
/* ... check for errors... */

◆ Cy_Crypto_Crc_CalcFinish()

cy_en_crypto_status_t Cy_Crypto_Crc_CalcFinish ( CRYPTO_Type *  base,
uint32_t *  crc,
cy_stc_crypto_crc_context_t *  crcContext 
)

This function completes the CRC calculation for message provided with Cy_Crypto_Crc_CalcPartial() function.

Once this function is called, call Cy_Crypto_Crc_CalcFree to free the CRC context.

Parameters
baseBase address of the Crypto block registers
crcPointer to store the computed CRC value
crcContextPointer to the CRC context structure cy_stc_crypto_crc_context_t allocated by the user. This structure is used by the Crypto driver for the CRC calculation. Do not modify the values of this structure.
Returns
cy_en_crypto_status_t
Function Usage
/* CRC parameters for some CRC algorithms:
+---------------------+-----+------------+------------+------+------+-----+------------+------------+
| CRC algorithm Name | CRC | Polynomial | Initial | Data | Data | Rem | Remainder | Expected |
| | len | | seed | REV | XOR | REV | XOR | CRC |
| ------------------- | --- | ---------- |----------- | ---- | ---- | --- | ---------- | ---------- |
| CRC-6 / CDMA2000-A | 6 | 0x27 | 0x3F | 0 | 0 | 0 | 0x00 | 0x0D |
| CRC-6 / CDMA2000-B | 6 | 0x07 | 0x3F | 0 | 0 | 0 | 0x00 | 0x3B |
| CRC-6 / DARC | 6 | 0x19 | 0x00 | 1 | 0 | 1 | 0x00 | 0x26 |
| CRC-6 / ITU | 6 | 0x03 | 0x00 | 1 | 0 | 1 | 0x00 | 0x06 |
| CRC-8 / ITU | 8 | 0x07 | 0x00 | 0 | 0 | 0 | 0x55 | 0xA1 |
| CRC-8 / MAXIM | 8 | 0x31 | 0x00 | 1 | 0 | 1 | 0x00 | 0xA1 |
| CRC-8 / ROHC | 8 | 0x07 | 0xFF | 1 | 0 | 1 | 0x00 | 0xD0 |
| CRC-8 / WCDMA | 8 | 0x9B | 0x00 | 1 | 0 | 1 | 0x00 | 0x25 |
| CRC-16 / CCITT-0 | 16 | 0x1021 | 0xFFFF | 0 | 0 | 0 | 0x0000 | 0x29B1 |
| CRC-16 / CDMA2000 | 16 | 0xC867 | 0xFFFF | 0 | 0 | 0 | 0x0000 | 0x4C06 |
| CRC-32 | 32 | 0x04C11DB7 | 0xFFFFFFFF | 1 | 0 | 1 | 0xFFFFFFFF | 0xCBF43926 |
| CRC-32 / BZIP2 | 32 | 0x04C11DB7 | 0xFFFFFFFF | 0 | 0 | 0 | 0xFFFFFFFF | 0xFC891918 |
+---------------------+-----+------------+------------+------+------+-----+------------+------------+
*/
/* Use "CRC-16/CCITT-0" calculation */
#define CRC16CCITT_WIDTH (16u)
#define CRC16CCITT_POLYNOMIAL (0x1021)
#define CRC16CCITT_LFSR_SEED (0xffff)
#define CRC16CCITT_DATA_REVERSE (0u)
#define CRC16CCITT_DATA_XOR (0u)
#define CRC16CCITT_REM_REVERSE (0u)
#define CRC16CCITT_REM_XOR (0x0000)
uint8_t message1[5] = "12345"; /* In this example, the message is processed in two parts - first 5 bytes, then 4 bytes */
uint8_t message2[4] = "6789";
uint32_t calculatedCrc = 0;
cy_stc_crypto_crc_context_t crcContext;
cy_en_crypto_status_t cryptoStatus;
/* Initialize Crypto CRC operation */
cryptoStatus = Cy_Crypto_Crc_CalcInit(
CRYPTO, /* Base address of the Crypto block registers */
CRC16CCITT_WIDTH, /* CRC width in bits */
CRC16CCITT_POLYNOMIAL, /* CRC polynomial (specified using 32 bits) */
CRC16CCITT_DATA_REVERSE, /* Byte order for processing: 0 - MSB first; 1 - LSB first */
CRC16CCITT_DATA_XOR, /* Byte mask for XORing data */
CRC16CCITT_REM_REVERSE, /* Reverse remainder */
CRC16CCITT_REM_XOR, /* Byte mask for XORing LFSR32 register */
CRC16CCITT_LFSR_SEED, /* LFSR initial seed */
&crcContext); /* Pointer to CRC context structure */
/* ... check for errors... */
/* Calculate CRC */
cryptoStatus = Cy_Crypto_Crc_CalcPartial(
CRYPTO, /* Base address of the Crypto block registers */
(void*)message1, /* Pointer to message */
sizeof(message1), /* Size of message */
&crcContext); /* Pointer to CRC context structure */
/* ... check for errors... */
/* Calculate CRC */
cryptoStatus = Cy_Crypto_Crc_CalcPartial(
CRYPTO, /* Base address of the Crypto block registers */
(void*)message2, /* Pointer to message */
sizeof(message2), /* Size of message */
&crcContext); /* Pointer to CRC context structure */
/* ... check for errors... */
/* Finish CRC */
cryptoStatus = Cy_Crypto_Crc_CalcFinish(
CRYPTO, /* Base address of the Crypto block registers */
&calculatedCrc, /* Pointer to CRC result */
&crcContext); /* Pointer to CRC context structure */
/* ... check for errors... */
/* Free the CRC context */
cryptoStatus = Cy_Crypto_Crc_CalcFree(
CRYPTO, /* Base address of the Crypto block registers */
&crcContext); /* Pointer to CRC context structure */
/* ... check for errors... */

◆ Cy_Crypto_Crc_CalcFree()

cy_en_crypto_status_t Cy_Crypto_Crc_CalcFree ( CRYPTO_Type *  base,
cy_stc_crypto_crc_context_t *  crcContext 
)

This function clears the CRC context.

Note
To start a new CRC calculation, call Cy_Crypto_Crc_CalcInit() again after this function call.
Parameters
baseBase address of the Crypto block registers.
crcContextPointer to the CRC context structure cy_stc_crypto_crc_context_t allocated by the user. This structure is used by the Crypto driver for the CRC calculation. Do not modify the values of this structure.
Returns
cy_en_crypto_status_t
Function Usage
/* CRC parameters for some CRC algorithms:
+---------------------+-----+------------+------------+------+------+-----+------------+------------+
| CRC algorithm Name | CRC | Polynomial | Initial | Data | Data | Rem | Remainder | Expected |
| | len | | seed | REV | XOR | REV | XOR | CRC |
| ------------------- | --- | ---------- |----------- | ---- | ---- | --- | ---------- | ---------- |
| CRC-6 / CDMA2000-A | 6 | 0x27 | 0x3F | 0 | 0 | 0 | 0x00 | 0x0D |
| CRC-6 / CDMA2000-B | 6 | 0x07 | 0x3F | 0 | 0 | 0 | 0x00 | 0x3B |
| CRC-6 / DARC | 6 | 0x19 | 0x00 | 1 | 0 | 1 | 0x00 | 0x26 |
| CRC-6 / ITU | 6 | 0x03 | 0x00 | 1 | 0 | 1 | 0x00 | 0x06 |
| CRC-8 / ITU | 8 | 0x07 | 0x00 | 0 | 0 | 0 | 0x55 | 0xA1 |
| CRC-8 / MAXIM | 8 | 0x31 | 0x00 | 1 | 0 | 1 | 0x00 | 0xA1 |
| CRC-8 / ROHC | 8 | 0x07 | 0xFF | 1 | 0 | 1 | 0x00 | 0xD0 |
| CRC-8 / WCDMA | 8 | 0x9B | 0x00 | 1 | 0 | 1 | 0x00 | 0x25 |
| CRC-16 / CCITT-0 | 16 | 0x1021 | 0xFFFF | 0 | 0 | 0 | 0x0000 | 0x29B1 |
| CRC-16 / CDMA2000 | 16 | 0xC867 | 0xFFFF | 0 | 0 | 0 | 0x0000 | 0x4C06 |
| CRC-32 | 32 | 0x04C11DB7 | 0xFFFFFFFF | 1 | 0 | 1 | 0xFFFFFFFF | 0xCBF43926 |
| CRC-32 / BZIP2 | 32 | 0x04C11DB7 | 0xFFFFFFFF | 0 | 0 | 0 | 0xFFFFFFFF | 0xFC891918 |
+---------------------+-----+------------+------------+------+------+-----+------------+------------+
*/
/* Use "CRC-16/CCITT-0" calculation */
#define CRC16CCITT_WIDTH (16u)
#define CRC16CCITT_POLYNOMIAL (0x1021)
#define CRC16CCITT_LFSR_SEED (0xffff)
#define CRC16CCITT_DATA_REVERSE (0u)
#define CRC16CCITT_DATA_XOR (0u)
#define CRC16CCITT_REM_REVERSE (0u)
#define CRC16CCITT_REM_XOR (0x0000)
uint8_t message[9] = "123456789";
uint32_t calculatedCrc = 0;
cy_stc_crypto_crc_context_t crcContext;
cy_en_crypto_status_t cryptoStatus;
/* Initialize Crypto CRC operation */
cryptoStatus = Cy_Crypto_Crc_CalcInit(
CRYPTO, /* Base address of the Crypto block registers */
CRC16CCITT_WIDTH, /* CRC width in bits*/
CRC16CCITT_POLYNOMIAL, /* CRC polynomial (specified using 32 bits) */
CRC16CCITT_DATA_REVERSE, /* Byte order for processing: 0 - MSB first; 1 - LSB first */
CRC16CCITT_DATA_XOR, /* Byte mask for XORing data */
CRC16CCITT_REM_REVERSE, /* Reverse remainder */
CRC16CCITT_REM_XOR, /* Byte mask for XORing LFSR32 register */
CRC16CCITT_LFSR_SEED, /* LFSR initial seed */
&crcContext); /* Pointer to CRC context structure */
/* ... check for errors... */
/* Calculate CRC */
cryptoStatus = Cy_Crypto_Crc_Calc(
CRYPTO, /* Base address of the Crypto block registers */
&calculatedCrc, /* Pointer to CRC result */
(void*)message, /* Pointer to message */
sizeof(message), /* Size of message */
&crcContext); /* Pointer to CRC context structure */
/* ... check for errors... */
/* Free the CRC context */
cryptoStatus = Cy_Crypto_Crc_CalcFree(
CRYPTO, /* Base address of the Crypto block registers */
&crcContext); /* Pointer to CRC context structure */
/* ... check for errors... */