Abov MC96F8204 Series

156
MC96F8204
ABOV Semiconductor Co., Ltd.
11.10 FLASH CRC/Checksum Generator
11.10.1 Overview
The Flash CRC(cyclic redundancy check) generator is used to get a 16-bit CRC code from Flash ROM and a
generator polynomial.
Among other applications, CRC-based techniques are used to verify data transmission or storage integrity. In the
scope of the functional safety standards, they offer a means of verifying the Flash memory integrity. The CRC
generator helps compute a signature of the software during runtime, to be compared with a reference signature.
The CRC generator has following features:
− Auto CRC and User CRC Mode
− CRC Clock : f
HFIRC
, f
HFIRC
/2, f
HFIRC
/4, f
HFIRC
/8 and fx (Main system clock)
− CRC-16 polynomial: 0x8C81
X16 + X15 + X11 + X10 + X7 +1
CRC: G(x) = x
16
+ x
15
+ x
11
+ x
10
+ x
7
+ 1
r0r1r2r3r4r5r6r7r8r9r10
r11r12r13r14r15
Input
(MSB first)
Figure 11.42 CRC-16 polynomial structure