libopencm3
A free/libre/open-source firmware library for various ARM Cortex-M3 microcontrollers.

Defined Constants and Types for the STM32Fxx CRC Generator More...

Collaboration diagram for CRC Defines:

Modules

 CRC Registers
 
 CRC_CR values
 

Macros

#define CRC_POL_DEFAULT   0x04C11DB7
 Default polynomial. More...
 

Functions

void crc_reset (void)
 Reset the CRC calculator to initial values. More...
 
uint32_t crc_calculate (uint32_t data)
 Writes a data word to the register, the write operation stalling until the computation is complete. More...
 
uint32_t crc_calculate_block (uint32_t *datap, int size)
 Add a block of data to the CRC calculator and return the final result. More...
 
void crc_reverse_output_enable (void)
 Enable reverse output data. More...
 
void crc_reverse_output_disable (void)
 Disable reverse output data. More...
 
void crc_set_reverse_input (uint32_t reverse_in)
 Reverse input data. More...
 
void crc_set_polysize (uint32_t polysize)
 Polynomial size. More...
 
void crc_set_polynomial (uint32_t polynomial)
 Polynomial coefficient. More...
 
void crc_set_initial (uint32_t initial)
 CRC Initial value. More...
 

Detailed Description

Defined Constants and Types for the STM32Fxx CRC Generator

Version
1.0.0
Date
29 Jun 2013

LGPL License Terms libopencm3 License

Author
© 2010 Thomas Otto tommi.nosp@m.@via.nosp@m.dmin..nosp@m.org
© 2016 Cem Basoglu cem.b.nosp@m.asog.nosp@m.lu@we.nosp@m.b.de

Macro Definition Documentation

◆ CRC_POL_DEFAULT

#define CRC_POL_DEFAULT   0x04C11DB7

Default polynomial.

Definition at line 90 of file crc_v2.h.

Function Documentation

◆ crc_calculate()

uint32_t crc_calculate ( uint32_t  data)

Writes a data word to the register, the write operation stalling until the computation is complete.

Parameters
[in]datanew word to add to the CRC calculator
Returns
int32 Computed CRC result

Definition at line 36 of file crc_common_all.c.

References CRC_DR.

◆ crc_calculate_block()

uint32_t crc_calculate_block ( uint32_t *  datap,
int  size 
)

Add a block of data to the CRC calculator and return the final result.

Writes data words consecutively to the register, the write operation stalling until the computation of each word is complete, then returns the final result

Parameters
[in]datappointer to an array of 32 bit data words.
[in]sizelength of data, in 32bit increments
Returns
final CRC calculator value

Definition at line 43 of file crc_common_all.c.

References CRC_DR.

◆ crc_reset()

void crc_reset ( void  )

Reset the CRC calculator to initial values.

Definition at line 31 of file crc_common_all.c.

References CRC_CR, and CRC_CR_RESET.

◆ crc_reverse_output_disable()

void crc_reverse_output_disable ( void  )

Disable reverse output data.

Disables the reversal of the bit order of the output data.

Definition at line 49 of file crc_v2.c.

References CRC_CR.

◆ crc_reverse_output_enable()

void crc_reverse_output_enable ( void  )

Enable reverse output data.

Enables the reversal of the bit order of the output data.

Definition at line 38 of file crc_v2.c.

References CRC_CR, and CRC_CR_REV_OUT.

◆ crc_set_initial()

void crc_set_initial ( uint32_t  initial)

CRC Initial value.

Sets the crc initial value.

Parameters
[in]initialUnsigned int32. CRC initial value.

Definition at line 110 of file crc_v2.c.

References CRC_INIT.

◆ crc_set_polynomial()

void crc_set_polynomial ( uint32_t  polynomial)

Polynomial coefficient.

Set the coefficients of the polynomial to be used for CRC calculation. If the polynomial size is less than 32-bits, the least significant bits have to be used to program the correct value.

Note
To obtain a reliable CRC calculation, any changes to the polynomial value or size can not be performed during a CRC calculation. As a result, if a CRC calculation is ongoing, the application must either reset the crc unit it or perform a CRC_DR read before changing the polynomial.
The default polynomial value is the CRC-32 (Ethernet) polynomial: 0x4C11DB7.
Parameters
[in]polynomialUnsigned int32. Polynomial coefficient.

Definition at line 98 of file crc_v2.c.

References CRC_POL.

◆ crc_set_polysize()

void crc_set_polysize ( uint32_t  polysize)

Polynomial size.

Set the size of the polynomial.

Parameters
[in]polysizeUnsigned int32. Size of polynomial CRC Polynomial size.

Definition at line 75 of file crc_v2.c.

References CRC_CR.

◆ crc_set_reverse_input()

void crc_set_reverse_input ( uint32_t  reverse_in)

Reverse input data.

Controls the reversal of the bit order of the input data

Parameters
[in]reverse_inUnsigned int32. Reversal bit order CRC Reverse input options.

Definition at line 61 of file crc_v2.c.

References CRC_CR.