Si102x/3x
13.2. Endianness
The CRC1 module is optimized to process big endian data. Data written to the CRC1IN SFR should be in
the normal bit order with the most significant bit stored in bit 7 and the least significant bit stored in bit 0.
The input data is shifted left into the CRC engine. The CRC1 module will process one byte at a time and
update the results for each byte. When used with the DMA, the first byte to be written should be stored in
the lowest address.
Some communications systems may transmit data least significant bit first and may require calculation of a
CRC in the transmission bit order. In this case, the bits must be flipped, using the CRC0FLIP SFR, before
writing to the CRC1IN SFR. The final 16-bit result may be flipped using the flip bit in the CRC1CN SFR.
Note that the polynomial is always written in big endian bit order.
170
Rev. 0.3
SILABS [ SILICON LABORATORIES ]
