Datasheet

dsPIC33FJ32GP302/304, dsPIC33FJ64GPX02/X04, AND dsPIC33FJ128GPX02/X04

25.5 Programmable CRC Registers

U-0 U-0 R/W-0 R-0 R-0 R-0 R-0 R-0

— — CSIDL VWORD<4:0>

bit 15 bit 8

R-0 R-1 U-0 R/W-0 R/W-0 R/W-0 R/W-0 R/W-0

CRCFUL CRCMPT

— CRCGO PLEN<3:0>

bit 7 bit 0

Legend:

R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’

-n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown

bit 15-14 Unimplemented: Read as ‘0’

bit 13 CSIDL: CRC Stop in Idle Mode bit

1 = Discontinue module operation when device enters Idle mode

0 = Continue module operation in Idle mode

bit 12-8 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> is

greater than 7, or 16 when PLEN<3:0> is less than or equal to 7.

bit 7 CRCFUL: FIFO Full bit

1 = FIFO is full

0 = FIFO is not full

bit 6 CRCMPT: FIFO Empty bit

1 = FIFO is empty

0 = FIFO is not empty

bit 5 Unimplemented: Read as ‘0’

bit 4 CRCGO: Start CRC bit

1 = Start CRC serial shifter

0 = Turn off CRC serial shifter after FIFO is empty

bit 3-0 PLEN<3:0>: Polynomial Length bits

Denotes the length of the polynomial to be generated minus 1.