Crc16_Check(); Description; Actions; Prototype - Infineon SP37 Function Manual

2.34

CRC16_Check()

2.34.1

Description

This function computes a 16-bit CRC of a code block from a start address with a defined length from FLASH, which
includes a pre-computed 16-bit CRC, which is stored in the last 2 Bytes of the memory block ((StartAddr + Length
- 2) is CRC High) and ((StartAddr + Length - 1) is CRC Low).
Note: The pre-computed CRC value has to be written by the application for code blocks in FLASH.
2.34.2

Actions

• Calculate 16-bit CRC
• Compare CRC with pre-computed CRC located in the last 2 Bytes of the code block
2.34.3

Prototype

signed char CRC16_Check(unsigned char code * StartAddr, unsigned int Length)
2.34.4

Inputs

Table 145 CRC16_Check: Input Parameters
Register / Address
R6 (MSB)
R7 (LSB)
R4 (MSB)
R5 (LSB)
2.34.5

Outputs

Table 146 CRC16_Check: Output values
Register/ Address
R7
ROM Library Function Guide
Type Name
unsigned char StartAddr
code*
unsigned int Length
Type Name
signed char Statusbyte
Tire Pressure Monitoring Sensor
Description
Pointer to first Byte of the Data that is used for
calculating the checksum
Length in Bytes of the code block, including the
pre-computed CRC value, that is used for
calculating the checksum.
Description
0: CRC matches
-1: CRC does not match
113
SP37
ROM Library Functions
Revision 1.0, 2011-12-15