Measuring Clock Frequency

[ctanto333]

I am traying to meassure a clcok frequency using STM32F103C8T6 board i am unable to capture. Please anyone solve my problem. This is the code i am using.

 

#include "main.h"
#include <stdio.h>
#include <string.h>

#define IDLE 0
#define DONE 1
#define F_CLK 72000000UL // System clock frequency for STM32F1xx

volatile uint8_t state = IDLE;
volatile uint8_t message[50] = {'\0'}; // Message buffer
volatile uint32_t T1 = 0; // First capture
volatile uint32_t T2 = 0; // Second capture
volatile uint32_t ticks = 0; // Time difference
volatile uint16_t TIM2_OVC = 0; // Timer overflow counter
volatile uint32_t frequency = 0; // Calculated frequency

TIM_HandleTypeDef htim2;
UART_HandleTypeDef huart1;

void SystemClock_Config(void);
static void MX_GPIO_Init(void);
static void MX_TIM2_Init(void);
static void MX_USART1_UART_Init(void);

int main(void)
{
 HAL_Init(); // Initialize HAL
 SystemClock_Config(); // Configure the system clock

 MX_GPIO_Init(); // Initialize GPIO
 MX_TIM2_Init(); // Initialize Timer 2
 MX_USART1_UART_Init(); // Initialize UART1

 // Start timer and input capture interrupts
 HAL_TIM_Base_Start_IT(&htim2); // Start timer overflow interrupt
 HAL_TIM_IC_Start_IT(&htim2, TIM_CHANNEL_1); // Start input capture on channel 1

 while (1)
 {
 // Main loop does nothing, frequency is measured in interrupts
 }
}

void HAL_TIM_IC_CaptureCallback(TIM_HandleTypeDef* htim)
{
 if (htim->Instance == TIM2 && htim->Channel == HAL_TIM_ACTIVE_CHANNEL_1)
 {
 if (state == IDLE)
 {
 T1 = TIM2->CCR1; // Capture first time
 TIM2_OVC = 0; // Reset overflow counter
 state = DONE;
 }
 else if (state == DONE)
 {
 T2 = TIM2->CCR1; // Capture second time
 ticks = (T2 + (TIM2_OVC * 65536)) - T1; // Calculate elapsed ticks
 if (ticks > 10) // Ignore very small intervals
 {
 frequency = (uint32_t)(F_CLK / ticks); // Calculate frequency
 sprintf((char*)message, "Frequency = %lu Hz\n\r", frequency);
 //HAL_UART_Transmit(&huart1, message, strlen((char*)message), 100); // Transmit frequency
 HAL_UART_Transmit(&huart1, (uint8_t*)message, strlen((char*)message), 100);
 }
 state = IDLE; // Reset state
 }
 }
}

void HAL_TIM_PeriodElapsedCallback(TIM_HandleTypeDef* htim)
{
 if (htim->Instance == TIM2)
 {
 TIM2_OVC++; // Increment overflow counter
 }
}

void SystemClock_Config(void)
{
 RCC_OscInitTypeDef RCC_OscInitStruct = {0};
 RCC_ClkInitTypeDef RCC_ClkInitStruct = {0};

 RCC_OscInitStruct.OscillatorType = RCC_OSCILLATORTYPE_HSE;
 RCC_OscInitStruct.HSEState = RCC_HSE_ON;
 RCC_OscInitStruct.HSEPredivValue = RCC_HSE_PREDIV_DIV1;
 RCC_OscInitStruct.HSIState = RCC_HSI_ON;
 RCC_OscInitStruct.PLL.PLLState = RCC_PLL_ON;
 RCC_OscInitStruct.PLL.PLLSource = RCC_PLLSOURCE_HSE;
 RCC_OscInitStruct.PLL.PLLMUL = RCC_PLL_MUL9;
 if (HAL_RCC_OscConfig(&RCC_OscInitStruct) != HAL_OK)
 {
 Error_Handler();
 }

 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_DIV1;
 RCC_ClkInitStruct.APB1CLKDivider = RCC_HCLK_DIV2;
 RCC_ClkInitStruct.APB2CLKDivider = RCC_HCLK_DIV1;

 if (HAL_RCC_ClockConfig(&RCC_ClkInitStruct, FLASH_LATENCY_2) != HAL_OK)
 {
 Error_Handler();
 }
}

static void MX_TIM2_Init(void)
{
 TIM_ClockConfigTypeDef sClockSourceConfig = {0};
 TIM_MasterConfigTypeDef sMasterConfig = {0};
 TIM_IC_InitTypeDef sConfigIC = {0};

 htim2.Instance = TIM2;
 htim2.Init.Prescaler = 0;
 htim2.Init.CounterMode = TIM_COUNTERMODE_UP;
 htim2.Init.Period = 65535;
 htim2.Init.ClockDivision = TIM_CLOCKDIVISION_DIV1;
 htim2.Init.AutoReloadPreload = TIM_AUTORELOAD_PRELOAD_ENABLE;
 if (HAL_TIM_Base_Init(&htim2) != HAL_OK)
 {
 Error_Handler();
 }
 sClockSourceConfig.ClockSource = TIM_CLOCKSOURCE_INTERNAL;
 if (HAL_TIM_ConfigClockSource(&htim2, &sClockSourceConfig) != HAL_OK)
 {
 Error_Handler();
 }
 if (HAL_TIM_IC_Init(&htim2) != HAL_OK)
 {
 Error_Handler();
 }
 sMasterConfig.MasterOutputTrigger = TIM_TRGO_RESET;
 sMasterConfig.MasterSlaveMode = TIM_MASTERSLAVEMODE_DISABLE;
 if (HAL_TIMEx_MasterConfigSynchronization(&htim2, &sMasterConfig) != HAL_OK)
 {
 Error_Handler();
 }
 sConfigIC.ICPolarity = TIM_INPUTCHANNELPOLARITY_RISING;
 sConfigIC.ICSelection = TIM_ICSELECTION_DIRECTTI;
 sConfigIC.ICPrescaler = TIM_ICPSC_DIV1;
 sConfigIC.ICFilter = 0;
 if (HAL_TIM_IC_ConfigChannel(&htim2, &sConfigIC, TIM_CHANNEL_1) != HAL_OK)
 {
 Error_Handler();
 }
}

static void MX_USART1_UART_Init(void)
{
 huart1.Instance = USART1;
 huart1.Init.BaudRate = 115200;
 huart1.Init.WordLength = UART_WORDLENGTH_8B;
 huart1.Init.StopBits = UART_STOPBITS_1;
 huart1.Init.Parity = UART_PARITY_NONE;
 huart1.Init.Mode = UART_MODE_TX_RX;
 huart1.Init.HwFlowCtl = UART_HWCONTROL_NONE;
 huart1.Init.OverSampling = UART_OVERSAMPLING_16;
 if (HAL_UART_Init(&huart1) != HAL_OK)
 {
 Error_Handler();
 }
}

static void MX_GPIO_Init(void)
{
 GPIO_InitTypeDef GPIO_InitStruct = {0};

 __HAL_RCC_GPIOA_CLK_ENABLE(); // Enable GPIOA clock

 // Configure PA0 as TIM2_CH1 input
 GPIO_InitStruct.Pin = GPIO_PIN_0;
 GPIO_InitStruct.Mode = GPIO_MODE_AF_PP;
 GPIO_InitStruct.Pull = GPIO_NOPULL;
 GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_LOW;
 HAL_GPIO_Init(GPIOA, &GPIO_InitStruct);
}

void Error_Handler(void)
{
 __disable_irq();
 while (1)
 {
 }
}

 

  

[MM..1]

Why not debug your code first? Check if is braek in 

HAL_TIM_IC_CaptureCallback