Hello Team, I would like to change the Frequency of the clock in two different threads. I tried 3 ways.
Hello Team,
I would like to change the Frequency of the clock in two different threads. I tried two ways.
1.
/* Enable HSE Oscillator and activate PLL with HSE as source */
RCC_OscInitStruct.OscillatorType = RCC_OSCILLATORTYPE_HSE;
RCC_OscInitStruct.HSEState = RCC_HSE_ON;
RCC_OscInitStruct.HSIState = RCC_HSI_OFF;
RCC_OscInitStruct.CSIState = RCC_CSI_OFF;
RCC_OscInitStruct.PLL.PLLState = RCC_PLL_ON;
RCC_OscInitStruct.PLL.PLLSource = RCC_PLLSOURCE_HSE;
RCC_ClkInitStruct.SYSCLKSource = RCC_SYSCLKSOURCE_PLLCLK;
2.
RCC_DeInit();
// Enable external crystal (HSE)
RCC_HSEConfig(RCC_HSE_ON);
// Wait until HSE ready to use or not
ErrorStatus errorStatus = RCC_WaitForHSEStartUp();
if (errorStatus == SUCCESS)
{
// Configure the PLL for 168MHz SysClk and 48MHz for USB OTG, SDIO
RCC_PLLConfig(RCC_PLLSource_HSE, 8, 336, 2, 7); // values changed for 144MHz
// Enable PLL
RCC_PLLCmd(ENABLE);
// Wait until main PLL clock ready
while (RCC_GetFlagStatus(RCC_FLAG_PLLRDY) == RESET);
// Set flash latency
FLASH_SetLatency(FLASH_Latency_5);
// AHB 168MHz
RCC_HCLKConfig(RCC_SYSCLK_Div1);
RCC_PCLK1Config(RCC_HCLK_Div4);
RCC_PCLK2Config(RCC_HCLK_Div2);
// Set SysClk using PLL
RCC_SYSCLKConfig(RCC_SYSCLKSource_PLLCLK);
}
else
{
// Do something to indicate that error clock configuration
while (1);
}
SystemCoreClockUpdate();
Second way RCC_PLLConfig() function is not present in drivers of STM32F4xxx drivers , please provide me the link of the github code where I can get RCC_PLLConfig() function definition.
3.
void Speed_Up_Clock()
{
uint16_t timeout;
/ Enable HSI clock /
RCC->CR |= RCC_CR_HSION;
/ Wait till HSI is ready /
timeout = 0xFFFF;
while (!(RCC->CR & RCC_CR_HSIRDY) && timeout--);
/ Select HSI clock as main clock /
RCC->CFGR = (RCC->CFGR & ~(RCC_CFGR_SW)) | RCC_CFGR_SW_HSI;
/ Disable PLL /
RCC->CR &= ~RCC_CR_PLLON;
SystemClock_Config(); //This is the STM32 generated function to configure the clock originally at program start
}
void Slow_Down_Clock()
{
uint16_t timeout;
/ Enable HSI clock /
RCC->CR |= RCC_CR_HSION;
/ Wait till HSI is ready /
timeout = 0xFFFF;
while (!(RCC->CR & RCC_CR_HSIRDY) && timeout--);
/ Select HSI clock as main clock /
RCC->CFGR = (RCC->CFGR & ~(RCC_CFGR_SW)) | RCC_CFGR_SW_HSI;
/ Disable PLL /
RCC->CR &= ~RCC_CR_PLLON;
RCC_OscInitTypeDef RCC_OscInitStruct;
RCC_ClkInitTypeDef RCC_ClkInitStruct;
RCC_PeriphCLKInitTypeDef PeriphClkInit;
/**Initializes the CPU, AHB and APB busses clocks
*/
RCC_OscInitStruct.OscillatorType = RCC_OSCILLATORTYPE_HSI;
RCC_OscInitStruct.HSIState = RCC_HSI_ON;
RCC_OscInitStruct.HSICalibrationValue = 16;
RCC_OscInitStruct.PLL.PLLState = RCC_PLL_ON;
RCC_OscInitStruct.PLL.PLLSource = RCC_PLLSOURCE_HSI;
RCC_OscInitStruct.PLL.PLLMUL = RCC_PLL_MUL4;
if (HAL_RCC_OscConfig(&RCC_OscInitStruct) != HAL_OK)
{
Error_Handler(__FILE_, __LINE__);
}
/**Initializes the CPU, AHB and APB busses clocks
*/
RCC_ClkInitStruct.ClockType = RCC_CLOCKTYPE_HCLK|RCC_CLOCKTYPE_SYSCLK
|RCC_CLOCKTYPE_PCLK1|RCC_CLOCKTYPE_PCLK2;
RCC_ClkInitStruct.SYSCLKSource = RCC_SYSCLKSOURCE_PLLCLK;
RCC_ClkInitStruct.AHBCLKDivider = RCC_SYSCLK_DIV4;
RCC_ClkInitStruct.APB1CLKDivider = RCC_HCLK_DIV2;
RCC_ClkInitStruct.APB2CLKDivider = RCC_HCLK_DIV1;
if (HAL_RCC_ClockConfig(&RCC_ClkInitStruct, FLASH_LATENCY_0) != HAL_OK)
{
Error_Handler(__FILE_, __LINE__);
}
PeriphClkInit.PeriphClockSelection = RCC_PERIPHCLK_TIM16|RCC_PERIPHCLK_TIM17
|RCC_PERIPHCLK_ADC1;
PeriphClkInit.Tim16ClockSelection = RCC_TIM16CLK_HCLK;
PeriphClkInit.Tim17ClockSelection = RCC_TIM17CLK_HCLK;
PeriphClkInit.Adc1ClockSelection = RCC_ADC1PLLCLK_DIV1;
if (HAL_RCCEx_PeriphCLKConfig(&PeriphClkInit) != HAL_OK)
{
Error_Handler(__FILE_, __LINE__);
}
/**Configure the Systick interrupt time
*/
HAL_SYSTICK_Config(HAL_RCC_GetHCLKFreq()/1000);
/**Configure the Systick
*/
HAL_SYSTICK_CLKSourceConfig(SYSTICK_CLKSOURCE_HCLK);
/ SysTick_IRQn interrupt configuration /
HAL_NVIC_SetPriority(SysTick_IRQn, 0, 0);
}
The above function doesn't help me to change the Frequency of the clock, So please suggest me a way to change my clock frequency for different thread execution in freeRTOS .
Please do the needful.
Thansks and Regards
Abhijith N.M.