GD32F20x User Manual
183
8.
CRC calculation unit (CRC)
8.1.
Overview
A cyclic redundancy check (CRC) is an error-detecting code commonly used in digital
networks and storage devices to detect accidental changes to raw data.
This CRC calculation unit can be used to calculate 32 bit CRC code with fixed polynomial.
8.2.
Characteristics
32-bit data input and 32-bit data output. Calculation period is 4 AHB clock cycles for
32-bit input data size from data entered to the calculation result available.
Free 8-bit register is unrelated to calculation and can be used for any other goals by
any other peripheral devices.
Fixed 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
This 32-bit CRC polynomial is a common polynomial used in Ethernet.
Figure 8-1. Block diagram of CRC calculation unit
AHB
BUS
Interface
Input Data Register (32 bit)
Output Data Register (32 bit)
Free Purpose Register (8 bit)
Data Input
Data Output
CRC Calculation Unit
Fixed polynomial
0x4C11DB7
Data Access
Summary of Contents for GD32F20 Series
Page 191: ...GD32F20x User Manual 191 Bits Fields Descriptions 31 0 TRNDATA 31 0 32 Bit Random data ...
Page 290: ...GD32F20x User Manual 290 conversion is ongoing ...
Page 325: ...GD32F20x User Manual 325 15 0 ALRM 15 0 RTC alarm value low ...
Page 385: ...GD32F20x User Manual 385 ...
Page 523: ...GD32F20x User Manual 523 clears AERR bit by writing 0 to it ...