PIC24F16KA102_11 Datasheet, PDF (169/278 Pages) Microchip Technology – 20/28-Pin General Purpose, 16-Bit Flash Microcontrollers with nanoWatt XLP Technology

PIC24F16KA102 FAMILY
20.3 Registers
There are four registers used to control programmable
CRC operation:
• CRCCON
• CRCXOR
• CRCDAT
• CRCWDAT
REGISTER 20-1: CRCCON: CRC CONTROL REGISTER
U-0
—
bit 15
U-0
R/W-0
R-0, HSC R-0, HSC
—
CSIDL
VWORD4 VWORD3
R-0, HSC
VWORD2
R-0, HSC
VWORD1
R-0, HSC
VWORD0
bit 8
R-0, HSC R-1, HSC
U-0
CRCFUL CRCMPT
—
bit 7
R/W-0
CRCGO
R/W-0
PLEN3
R/W-0
PLEN2
R/W-0
PLEN1
R/W-0
PLEN0
bit 0
Legend:
R = Readable bit
-n = Value at POR
HSC = Hardware Settable/Clearable bit
W = Writable bit
U = Unimplemented bit, read as ‘0’
‘1’ = Bit is set
‘0’ = Bit is cleared
x = Bit is unknown
bit 15-14
bit 13
bit 12-8
bit 7
bit 6
bit 5
bit 4
bit 3-0
Unimplemented: Read as ‘0’
CSIDL: CRC Stop in Idle Mode bit
1 = Discontinue module operation when device enters Idle mode
0 = Continue module operation in Idle mode
VWORD<4:0>: Pointer Value bits
Indicates the number of valid words in the FIFO. Has a maximum value of 8 when PLEN<3:0> > 7, or
16 when PLEN<3:0> 7.
CRCFUL: FIFO Full bit
1 = FIFO is full
0 = FIFO is not full
CRCMPT: FIFO Empty Bit
1 = FIFO is empty
0 = FIFO is not empty
Unimplemented: Read as ‘0’
CRCGO: Start CRC bit
1 = Start CRC serial shifter
0 = CRC serial shifter is turned off
PLEN<3:0>: Polynomial Length bits
Denotes the length of the polynomial to be generated minus 1.
 2008-2011 Microchip Technology Inc.
DS39927C-page 169