2019-08-05 13:14:59 +01:00

365 lines
10 KiB
C

/**
******************************************************************************
* @file Examples_LL/CRC/CRC_UserDefinedPolynomial/Src/main.c
* @author MCD Application Team
* @brief This example describes how to use CRC peripheral for generating 8-bit CRC value
* for an input data Buffer, based on a user defined polynomial value,
* using the STM32F7xx CRC LL API.
* Peripheral initialization done using LL unitary services functions.
******************************************************************************
* @attention
*
* <h2><center>&copy; Copyright (c) 2016 STMicroelectronics.
* All rights reserved.</center></h2>
*
* This software component is licensed by ST under BSD 3-Clause license,
* the "License"; You may not use this file except in compliance with the
* License. You may obtain a copy of the License at:
* opensource.org/licenses/BSD-3-Clause
*
******************************************************************************
*/
/* Includes ------------------------------------------------------------------*/
#include "main.h"
/** @addtogroup STM32F7xx_LL_Examples
* @{
*/
/** @addtogroup CRC_UserDefinedPolynomial
* @{
*/
/* Private typedef -----------------------------------------------------------*/
/* Private define ------------------------------------------------------------*/
#define BUFFER_SIZE 39 /* 9 u32 + 1 u16 + 1 u8 */
/* 8-bit long user defined Polynomial value for this example
In this example, the polynomial is set manually to 0x9B
that is X^8 + X^7 + X^4 + X^3 + X + 1. */
#define CRC8_POLYNOMIAL_VALUE 0x9B
/* Private macro -------------------------------------------------------------*/
/* Private variables ---------------------------------------------------------*/
/* Used for storing CRC Value */
__IO uint8_t ubCRCValue = 0;
static const uint8_t aDataBuffer[BUFFER_SIZE] =
{
0x21, 0x10, 0x00, 0x00, 0x63, 0x30, 0x42, 0x20, 0xa5, 0x50, 0x84, 0x40,
0xe7, 0x70, 0xc6, 0x60, 0x4a, 0xa1, 0x29, 0x91, 0x8c, 0xc1, 0x6b, 0xb1,
0xce, 0xe1, 0xad, 0xd1, 0x31, 0x12, 0xef, 0xf1, 0x52, 0x22, 0x73, 0x32,
0xa1, 0xb2, 0xc3
};
/* Expected CRC Value */
uint8_t ubExpectedCRCValue = 0xA6;
/* Private function prototypes -----------------------------------------------*/
void SystemClock_Config(void);
void Configure_CRC(void);
uint8_t Calculate_CRC(uint32_t);
void CheckCRCResultValue(void);
void LED_Init(void);
void LED_On(void);
void LED_Blinking(uint32_t Period);
static void CPU_CACHE_Enable(void);
/* Private functions ---------------------------------------------------------*/
/**
* @brief Main program
* @param None
* @retval None
*/
int main(void)
{
/* Enable the CPU Cache */
CPU_CACHE_Enable();
/* Configure the system clock to 216 MHz */
SystemClock_Config();
/* Initialize LED1 */
LED_Init();
/* Configure CRC (CRC IP configuration using user-defined Polynomial value) */
Configure_CRC();
/* Perform CRC calculation on data contained in aDataBuffer */
ubCRCValue = Calculate_CRC(BUFFER_SIZE);
/* Check if CRC computed result value is equal to expected one */
CheckCRCResultValue();
/* Infinite loop */
while (1)
{
}
}
/**
* @brief This function configures CRC Instance.
* @note This function is used to :
* -1- Enable peripheral clock for CRC.
* -2- Configure CRC functional parameters.
* @note Peripheral configuration is minimal configuration from reset values.
* Thus, some useless LL unitary functions calls below are provided as
* commented examples - setting is default configuration from reset.
* @param None
* @retval None
*/
void Configure_CRC(void)
{
/* (1) Enable peripheral clock for CRC *********************/
LL_AHB1_GRP1_EnableClock(LL_AHB1_GRP1_PERIPH_CRC);
/* (2) Configure CRC functional parameters ********************************/
/* Configure CRC calculation unit with user defined polynomial value, 8-bit long */
LL_CRC_SetPolynomialCoef(CRC, CRC8_POLYNOMIAL_VALUE);
LL_CRC_SetPolynomialSize(CRC, LL_CRC_POLYLENGTH_8B);
/* Initialize default CRC initial value */
/* Reset value is LL_CRC_DEFAULT_CRC_INITVALUE */
// LL_CRC_SetInitialData(CRC, LL_CRC_DEFAULT_CRC_INITVALUE);
/* Set input data inversion mode : No inversion*/
/* Reset value is LL_CRC_INDATA_REVERSE_NONE */
// LL_CRC_SetInputDataReverseMode(CRC, LL_CRC_INDATA_REVERSE_NONE);
/* Set output data inversion mode : No inversion */
/* Reset value is LL_CRC_OUTDATA_REVERSE_NONE */
// LL_CRC_SetOutputDataReverseMode(CRC, LL_CRC_OUTDATA_REVERSE_NONE);
}
/**
* @brief This function performs CRC calculation on BufferSize bytes from input data buffer aDataBuffer.
* @param BufferSize Nb of bytes to be processed for CRC calculation
* @retval 8-bit CRC value computed on input data buffer
*/
uint8_t Calculate_CRC(uint32_t BufferSize)
{
register uint32_t data = 0;
register uint32_t index = 0;
/* Compute the CRC of Data Buffer array*/
for (index = 0; index < (BufferSize / 4); index++)
{
data = (uint32_t)((aDataBuffer[4 * index + 3] << 24) | (aDataBuffer[4 * index + 2] << 16) | (aDataBuffer[4 * index + 1] << 8) | aDataBuffer[4 * index]);
LL_CRC_FeedData32(CRC, data);
}
/* Last bytes specific handling */
if ((BUFFER_SIZE % 4) != 0)
{
if (BUFFER_SIZE % 4 == 1)
{
LL_CRC_FeedData8(CRC, aDataBuffer[4 * index]);
}
if (BUFFER_SIZE % 4 == 2)
{
LL_CRC_FeedData16(CRC, (uint16_t)((aDataBuffer[4 * index + 1]<<8) | aDataBuffer[4 * index]));
}
if (BUFFER_SIZE % 4 == 3)
{
LL_CRC_FeedData16(CRC, (uint16_t)((aDataBuffer[4 * index + 1]<<8) | aDataBuffer[4 * index]));
LL_CRC_FeedData8(CRC, aDataBuffer[4 * index + 2]);
}
}
/* Return computed CRC value */
return(LL_CRC_ReadData8(CRC));
}
/**
* @brief Check CRC computation result value.
* @param None
* @retval None
*/
void CheckCRCResultValue(void)
{
/* Compare the CRC value to the Expected one */
if (ubCRCValue != ubExpectedCRCValue)
{
/* Wrong CRC value: Set LED1 to Blinking mode (Error) */
LED_Blinking(LED_BLINK_ERROR);
}
else
{
/* Right CRC value: Turn LED1 on */
LED_On();
}
}
/**
* @brief Initialize LED1.
* @param None
* @retval None
*/
void LED_Init(void)
{
/* Enable the LED1 Clock */
LED1_GPIO_CLK_ENABLE();
/* Configure IO in output push-pull mode to drive external LED1 */
LL_GPIO_SetPinMode(LED1_GPIO_PORT, LED1_PIN, LL_GPIO_MODE_OUTPUT);
/* Reset value is LL_GPIO_OUTPUT_PUSHPULL */
//LL_GPIO_SetPinOutputType(LED1_GPIO_PORT, LED1_PIN, LL_GPIO_OUTPUT_PUSHPULL);
/* Reset value is LL_GPIO_SPEED_FREQ_LOW */
//LL_GPIO_SetPinSpeed(LED1_GPIO_PORT, LED1_PIN, LL_GPIO_SPEED_FREQ_LOW);
/* Reset value is LL_GPIO_PULL_NO */
//LL_GPIO_SetPinPull(LED1_GPIO_PORT, LED1_PIN, LL_GPIO_PULL_NO);
}
/**
* @brief Turn-on LED1.
* @param None
* @retval None
*/
void LED_On(void)
{
/* Turn LED1 on */
LL_GPIO_SetOutputPin(LED1_GPIO_PORT, LED1_PIN);
}
/**
* @brief Set LED1 to Blinking mode for an infinite loop (toggle period based on value provided as input parameter).
* @param Period : Period of time (in ms) between each toggling of LED
* This parameter can be user defined values. Pre-defined values used in that example are :
* @arg LED_BLINK_FAST : Fast Blinking
* @arg LED_BLINK_SLOW : Slow Blinking
* @arg LED_BLINK_ERROR : Error specific Blinking
* @retval None
*/
void LED_Blinking(uint32_t Period)
{
/* Toggle IO in an infinite loop */
while (1)
{
LL_GPIO_TogglePin(LED1_GPIO_PORT, LED1_PIN);
LL_mDelay(Period);
}
}
/**
* @brief System Clock Configuration
* The system Clock is configured as follow :
* System Clock source = PLL (HSE)
* SYSCLK(Hz) = 216000000
* HCLK(Hz) = 216000000
* AHB Prescaler = 1
* APB1 Prescaler = 4
* APB2 Prescaler = 2
* HSI Frequency(Hz) = 8000000
* PLL_M = 8
* PLL_N = 432
* PLL_P = 2
* VDD(V) = 3.3
* Main regulator output voltage = Scale1 mode
* Flash Latency(WS) = 7
* @param None
* @retval None
*/
void SystemClock_Config(void)
{
/* Enable HSE clock */
LL_RCC_HSE_EnableBypass();
LL_RCC_HSE_Enable();
while(LL_RCC_HSE_IsReady() != 1)
{
};
/* Set FLASH latency */
LL_FLASH_SetLatency(LL_FLASH_LATENCY_7);
/* Enable PWR clock */
LL_APB1_GRP1_EnableClock(LL_APB1_GRP1_PERIPH_PWR);
/* Activation OverDrive Mode */
LL_PWR_EnableOverDriveMode();
while(LL_PWR_IsActiveFlag_OD() != 1)
{
};
/* Activation OverDrive Switching */
LL_PWR_EnableOverDriveSwitching();
while(LL_PWR_IsActiveFlag_ODSW() != 1)
{
};
/* Main PLL configuration and activation */
LL_RCC_PLL_ConfigDomain_SYS(LL_RCC_PLLSOURCE_HSE, LL_RCC_PLLM_DIV_8, 432, LL_RCC_PLLP_DIV_2);
LL_RCC_PLL_Enable();
while(LL_RCC_PLL_IsReady() != 1)
{
};
/* Sysclk activation on the main PLL */
LL_RCC_SetAHBPrescaler(LL_RCC_SYSCLK_DIV_1);
LL_RCC_SetSysClkSource(LL_RCC_SYS_CLKSOURCE_PLL);
while(LL_RCC_GetSysClkSource() != LL_RCC_SYS_CLKSOURCE_STATUS_PLL)
{
};
/* Set APB1 & APB2 prescaler */
LL_RCC_SetAPB1Prescaler(LL_RCC_APB1_DIV_4);
LL_RCC_SetAPB2Prescaler(LL_RCC_APB2_DIV_2);
/* Set systick to 1ms */
SysTick_Config(216000000 / 1000);
/* Update CMSIS variable (which can be updated also through SystemCoreClockUpdate function) */
SystemCoreClock = 216000000;
}
/**
* @brief CPU L1-Cache enable.
* @param None
* @retval None
*/
static void CPU_CACHE_Enable(void)
{
/* Enable I-Cache */
SCB_EnableICache();
/* Enable D-Cache */
SCB_EnableDCache();
}
#ifdef USE_FULL_ASSERT
/**
* @brief Reports the name of the source file and the source line number
* where the assert_param error has occurred.
* @param file: pointer to the source file name
* @param line: assert_param error line source number
* @retval None
*/
void assert_failed(uint8_t *file, uint32_t line)
{
/* User can add his own implementation to report the file name and line number,
ex: printf("Wrong parameters value: file %s on line %d", file, line) */
/* Infinite loop */
while (1)
{
}
}
#endif
/**
* @}
*/
/**
* @}
*/
/************************ (C) COPYRIGHT STMicroelectronics *****END OF FILE****/