The DACx300x
implement a cyclic redundancy check (CRC) feature for the NVM to
make sure that the data stored in the NVM is uncorrupted. There are
two types of CRC alarm bits implemented in DACx300x:
- NVM-CRC-FAIL-USER
- NVM-CRC-FAIL-INT
The NVM-CRC-FAIL-USER bit indicates the status of
user-programmable NVM bits, and the NVM-CRC-FAIL-INT bit indicates
the status of internal NVM bits The CRC feature is implemented by
storing a 16-bit CRC (CRC-16-CCITT) along with the NVM data each
time NVM program operation (write or reload) is performed and during
the device start-up. The device reads the NVM data and validates the
data with the stored CRC. The CRC alarm bits (NVM-CRC-FAIL-USER and
NVM-CRC-FAIL-INT in the GENERAL-STATUS register) report any errors
after the data are read from the device NVM. The alarm bits are set
only at boot up.