stm32出4mhz的频率信号
时间: 2023-06-05 09:47:30 浏览: 110
要输出4MHz频率的信号,可以采用STM32的TIM定时器模块和GPIO输出模式。
首先,需要配置定时器的时钟源和预分频系数。对于系统时钟为72MHz的STM32F103C8T6,可以使用内部时钟源和预分频系数8,得到9MHz计数频率,再通过定时器的自动重装载值来得到4MHz的输出频率。
其次,需要在GPIO中选择一个输出引脚,并将其设置为复用功能(mode设置为复用输出),输出频率将通过该引脚输出。
最后,需要在此代码中打开TIM定时器并开始输出频率即可。可以使用CubeMX配置工具生成相应代码。
示例代码如下:
```
#include "stm32f1xx_hal.h"
TIM_HandleTypeDef htim;
void SystemClock_Config(void);
static void MX_GPIO_Init(void);
static void MX_TIM3_Init(void);
int main(void)
{
HAL_Init();
SystemClock_Config();
MX_GPIO_Init();
MX_TIM3_Init();
while (1)
{
}
}
void SystemClock_Config(void)
{
RCC_OscInitTypeDef RCC_OscInitStruct = {0};
RCC_ClkInitTypeDef RCC_ClkInitStruct = {0};
__HAL_RCC_PWR_CLK_ENABLE();
__HAL_PWR_VOLTAGESCALING_CONFIG(PWR_REGULATOR_VOLTAGE_SCALE1);
RCC_OscInitStruct.OscillatorType = RCC_OSCILLATORTYPE_HSE|RCC_OSCILLATORTYPE_LSE;
RCC_OscInitStruct.HSEState = RCC_HSE_ON;
RCC_OscInitStruct.LSEState = RCC_LSE_ON;
RCC_OscInitStruct.HSEPredivValue = RCC_HSE_PREDIV_DIV1;
RCC_OscInitStruct.LSEPredivValue = RCC_LSE_PREDIV_DIV1;
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_DIV4;
RCC_ClkInitStruct.APB2CLKDivider = RCC_HCLK_DIV1;
if (HAL_RCC_ClockConfig(&RCC_ClkInitStruct, FLASH_LATENCY_2) != HAL_OK)
{
Error_Handler();
}
}
static void MX_TIM3_Init(void)
{
TIM_OC_InitTypeDef sConfigOC = {0};
TIM_MasterConfigTypeDef sMasterConfig = {0};
htim.Instance = TIM3;
htim.Init.Prescaler = 8-1;
htim.Init.CounterMode = TIM_COUNTERMODE_UP;
htim.Init.Period = 9-1;
htim.Init.ClockDivision = TIM_CLOCKDIVISION_DIV1;
if (HAL_TIM_Base_Init(&htim) != HAL_OK)
{
Error_Handler();
}
sConfigOC.OCMode = TIM_OCMODE_TOGGLE;
sConfigOC.Pulse = 4-1;
if (HAL_TIM_OC_ConfigChannel(&htim, &sConfigOC, TIM_CHANNEL_1) != HAL_OK)
{
Error_Handler();
}
sMasterConfig.MasterOutputTrigger = TIM_TRGO_OC1;
sMasterConfig.MasterSlaveMode = TIM_MASTERSLAVEMODE_DISABLE;
if (HAL_TIMEx_MasterConfigSynchronization(&htim, &sMasterConfig) != HAL_OK)
{
Error_Handler();
}
HAL_TIM_Base_Start(&htim);
}
static void MX_GPIO_Init(void)
{
GPIO_InitTypeDef GPIO_InitStruct = {0};
__HAL_RCC_GPIOC_CLK_ENABLE();
GPIO_InitStruct.Pin = GPIO_PIN_13;
GPIO_InitStruct.Mode = GPIO_MODE_AF_PP;
GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_HIGH;
HAL_GPIO_Init(GPIOC, &GPIO_InitStruct);
}
```