Microchip Technology MA330028 Data Sheet

 2011-2013 Microchip Technology Inc.

DS70000657H-page 373

The programmable CRC generator offers the following
features:
• User-programmable (up to 32nd order) 

polynomial CRC equation

• Interrupt output
• Data FIFO
The programmable CRC generator provides a
hardware implemented method of quickly generating
checksums for various networking and security
applications. It offers the following features:
• User-programmable CRC polynomial equation, 

up to 32 bits

• Programmable shift direction (little or big-endian)
• Independent data and polynomial lengths
• Configurable interrupt output
• Data FIFO
A simplified block diagram of the CRC generator is
shown in 

. A simple version of the CRC shift

engine is shown in 

This data sheet summarizes the
features of the dsPIC33EPXXXGP50X,
dsPIC33EPXXXMC20X/50X and
PIC24EPXXXGP/MC20X families of
devices. It is not intended to be a compre-
hensive reference source. To complement
the information in this data sheet, refer to
“Programmable Cyclic Redundancy
Check (CRC)”

 (DS70346) of the

“dsPIC33/PIC24 Family Reference Man-
ual

”, which is available from the Microchip

www.microchip.com

).

Some registers and associated bits
described in this section may not be
available on all devices. Refer to

 in

this data sheet for device-specific register
and bit information.

Variable FIFO

(4x32, 8x16 or 16x8)

Shift Buffer

CRC Shift Engine

LENDIAN

1

0

CRCISEL

1

0

FIFO Empty Event 

Shift Complete Event

Set CRCIF

2 * F

P

 Shift Clock