/**
* \brief Compute 16-bit CRC for EEPROM address range using hardware CRC module.
*
* This function returns the 16-bit CRC of the specified EEPROM address range.
*
* \param origDataptr Address of EEPROM location to start CRC computation at.
* \param numBytes Number of bytes of the data.
* \param pchecksum Pointer to the checksum stored in EEPROM.
*
* \note No sanity checking of addresses is done.
*/
uint16_t CLASSB_CRC16_EEPROM_HW(eepromptr_t origDataptr, crcbytenum_t numBytes,
eeprom_uint16ptr_t pchecksum)
{
uint32_t checksum;
eeprom_uint8ptr_t dataptr = origDataptr;
crc_set_initial_value(CRC16_INITIAL_REMAINDER);
/* Ensure that EEPROM is memory mapped. */
CLASSB_EEMAP_BEGIN();
dataptr += MAPPED_EEPROM_START;
checksum = crc_io_checksum((void*)dataptr, numBytes, CRC_16BIT);
#if defined(__ICCAVR__)
/* Disable memory mapping of EEPROM, if necessary. */
CLASSB_EEMAP_END();
/* Compare checksums and handle error if necessary. */
if (checksum != *pchecksum) {
CLASSB_ERROR_HANDLER_CRC();
}
#elif defined(__GNUC__)
/* Compare checksums and handle error if necessary. */
if (checksum != (*(eeprom_uint16ptr_t)(MAPPED_EEPROM_START
+ (uintptr_t)pchecksum))) {
CLASSB_ERROR_HANDLER_CRC();
}
/* Disable memory mapping of EEPROM, if necessary. */
CLASSB_EEMAP_END();
#endif
/* Return 16 bits */
return checksum & (uint32_t)0x0000FFFF;
}
/**
* \brief Compute 32-bit CRC for EEPROM address range using table lookup.
*
* This function returns the 32-bit CRC of the specified EEPROM address range.
*
* \param origDataptr Address of EEPROM location to start CRC computation at.
* \param numBytes Number of bytes of the data.
* \param pchecksum Pointer to the checksum stored in EEPROM.
*
* \note No sanity checking of addresses is done.
*/
uint32_t CLASSB_CRC32_EEPROM_SW(eepromptr_t origDataptr, crcbytenum_t numBytes,
eeprom_uint32ptr_t pchecksum)
{
eeprom_uint8ptr_t dataptr = origDataptr;
uint32_t remainder = CRC32_INITIAL_REMAINDER;
uint8_t dataTemp;
/* Ensure that EEPROM is memory mapped. */
CLASSB_EEMAP_BEGIN();
dataptr += MAPPED_EEPROM_START;
/* Compute CRC for the specified data. */
for (; numBytes != 0; numBytes--) {
dataTemp = *dataptr++;
#if defined(CRC_USE_32BIT_LOOKUP_TABLE)
CLASSB_CRC_REFL_TABLE_32(dataTemp, remainder,
CLASSB_CRC32Table);
#else
CLASSB_CRC_REFL(dataTemp, remainder, CRC32_POLYNOMIAL, 32);
#endif
}
#ifdef CRC32_FINAL_XOR_VALUE
remainder ^= CRC32_FINAL_XOR_VALUE;
#endif
#if defined(__ICCAVR__)
/* Disable memory mapping of EEPROM, if necessary. */
CLASSB_EEMAP_END();
/* Compare checksums and handle error if necessary. */
if (remainder != *pchecksum) {
CLASSB_ERROR_HANDLER_CRC();
}
#elif defined(__GCC__)
/* Compare checksums and handle error if necessary. */
if (remainder != (*(eeprom_uint32ptr_t)(MAPPED_EEPROM_START
+ (uintptr_t) pchecksum))) {
CLASSB_ERROR_HANDLER_CRC();
}
/* Disable memory mapping of EEPROM, if necessary. */
CLASSB_EEMAP_END();
#endif
return remainder;
}
/**
* \brief Compute 16-bit CRC for Flash address range using hardware CRC module.
*
* This function returns the 16-bit CRC of the specified Flash address range.
*
* \param origDataptr Address of Flash location to start CRC computation at.
* \param numBytes Number of bytes of the data.
* \param pchecksum Pointer to the checksum stored in EEPROM.
*
* \note 16-bit flash CRC is much slower than 32-bit for flash checking.
* \note No sanity checking of addresses is done.
*/
uint16_t CLASSB_CRC16_Flash_HW(flashptr_t origDataptr, crcbytenum_t numBytes,
eeprom_uint16ptr_t pchecksum)
{
uint32_t checksum;
flash_uint8ptr_t dataptr = origDataptr;
uint8_t dataTemp;
crc_set_initial_value(CRC16_INITIAL_REMAINDER);
crc_io_checksum_byte_start(CRC_16BIT);
/* Compute CRC for the specified data. */
for (; numBytes != 0; numBytes--) {
#if (PROGMEM_SIZE >= 0x10000UL)
dataTemp = PROGMEM_READ_BYTE(dataptr++);
#else
dataTemp = PROGMEM_READ_BYTE(dataptr++);
#endif
crc_io_checksum_byte_add(dataTemp);
}
checksum = crc_io_checksum_byte_stop();
#if defined(__ICCAVR__)
/* Compare checksums and handle error if necessary. */
if (checksum != *pchecksum) {
CLASSB_ERROR_HANDLER_CRC();
}
#elif defined(__GCC__)
/* Ensure that EEPROM is memory mapped. */
CLASSB_EEMAP_BEGIN();
/* Compare checksums and handle error if necessary. */
if (checksum != (*(eeprom_uint16ptr_t)(MAPPED_EEPROM_START
+ (uintptr_t)pchecksum))) {
CLASSB_ERROR_HANDLER_CRC();
}
/* Disable memory mapping of EEPROM, if necessary. */
CLASSB_EEMAP_END();
#endif
/* Return 16 bits */
return checksum & (uint32_t)0x0000FFFF;
}
/**
* \brief Compute 16-bit CRC for Flash address range using table lookup.
*
* This function returns the 16-bit CRC of the specified Flash address range.
*
* \param origDataptr Address of Flash location to start CRC computation at.
* \param numBytes Number of bytes of the data.
* \param pchecksum Pointer to the checksum stored in EEPROM.
*
* \note No sanity checking of addresses is done.
*/
uint16_t CLASSB_CRC16_Flash_SW(flashptr_t origDataptr, crcbytenum_t numBytes,
eeprom_uint16ptr_t pchecksum)
{
flash_uint8ptr_t dataptr = origDataptr;
uint16_t remainder = CRC16_INITIAL_REMAINDER;
uint8_t dataTemp;
/* Compute CRC for the specified data. */
for (; numBytes != 0; numBytes--) {
#if (PROGMEM_SIZE >= 0x10000UL)
dataTemp = PROGMEM_READ_BYTE(dataptr++);
#else
dataTemp = PROGMEM_READ_BYTE(dataptr++);
#endif
#if defined(CRC_USE_16BIT_LOOKUP_TABLE)
CLASSB_CRC_TABLE_16(dataTemp, remainder, CLASSB_CRC16Table);
#else
CLASSB_CRC(dataTemp, remainder, CRC16_POLYNOMIAL, 16);
#endif
}
#if defined(__ICCAVR__)
/* Compare checksums and handle error if necessary. */
if (remainder != *pchecksum) {
CLASSB_ERROR_HANDLER_CRC();
}
#elif defined(__GCC__)
/* Ensure that EEPROM is memory mapped. */
CLASSB_EEMAP_BEGIN();
/* Compare checksums and handle error if necessary. */
if (remainder != (*(eeprom_uint16ptr_t)(MAPPED_EEPROM_START
+ (uintptr_t) pchecksum))) {
CLASSB_ERROR_HANDLER_CRC();
}
/* Disable memory mapping of EEPROM, if necessary. */
CLASSB_EEMAP_END();
#endif
return (remainder);
}
