SWRU543B January 2019 – June 2025 CC3230S , CC3230SF , CC3235MODS , CC3235MODSF , CC3235S , CC3235SF
The CRC module supports data being fed 32-bit words and 8 bits at a time, and can dynamically switch back and forth. The data size is configured by programming the SIZE bit in the CRCCTRL register, offset 0xC00.
Because CRC is a division on a long stream of bits, the application must consider the bit order. When processing message data that is read out by words, bit order is not an issue. For example, if the data value in the message is 0x12345678, the most significant 8 bytes is 0x12 (00010010 in binary). If the data is processed as bytes, 0x12, 0x34, 0x56, and 0x78 are copied into memory in that order and the word is stored as 0x78563412, where 0x12 is written as byte 0, 0x34 is written as byte 1, and so forth.