C8051F980-C-GM Datasheet, PDF (179/325 Pages) Silicon Laboratories – Ultra Low Power, 8-2 kB Flash, Capacitive Sensing MCU

C8051F99x-C8051F98x
16.5. CRC0 Bit Reverse Feature
CRC0 includes hardware to reverse the bit order of each bit in a byte as shown in Figure 16.2. Each byte
of data written to CRC0FLIP is read back bit reversed. For example, if 0xC0 is written to CRC0FLIP, the
data read back is 0x03. Bit reversal is a useful mathematical function used in algorithms such as the FFT.
CRC0FLIP
Write
CRC0FLIP
Read
Figure 16.2. Bit Reverse Register
SFR Definition 16.6. CRC0FLIP: CRC0 Bit Flip
Bit
7
6
5
4
3
2
1
0
Name
CRC0FLIP[7:0]
Type
R/W
Reset
0
0
0
0
0
0
0
0
SFR Page = All; SFR Address = 0x9C
Bit
Name
Function
7:0 CRC0FLIP[7:0] CRC0 Bit Flip.
Any byte written to CRC0FLIP is read back in a bit-reversed order, i.e. the written
LSB becomes the MSB. For example:
If 0xC0 is written to CRC0FLIP, the data read back will be 0x03.
If 0x05 is written to CRC0FLIP, the data read back will be 0xA0.
Rev. 1.2
179