CRC计算单元
功能外设
CRC Features (1/4)
CRC-based techniques are used to verify storage integrity or data transmission
In functional safety standards (such as EN/IEC 60335-1), CRC peripheral offers a
means of verifying the embedded Flash memory integrity
Uses CRC-32 (Ethernet) polynomial: 0x4C11DB7 :
X
32
+ X
26
+ X
23
+ X
22
+ X
16
+ X
12
+ X
11
+ X
10
+ X
8
+ X
7
+ X
5
+ X
4
+ X
2
+ X + 1
CRC computation (polynomial:0x4C11DB7)
Data register (Input)
Data register (Output)
AHB Bus
32-bit (read access)
Single input/output 32-bit data register, but
handles 8,16 and 32-bits data size
CRC Peripheral is mapped to AHB bus for
fast operation, CRC computation done in 4
AHB clock cycles (HCLK) maximum
Computation duration depends on data size
4 HCLK cycles for 32-bit
2 HCLK cycles for 16-bit
1 HCLK cycle for 8-bit
General-purpose 8-bit register (can be used
for temporary storage)
1
32-bit (write access)
