使用 TIM3 设计一个电子时钟。通过串口每秒输出一次时分秒信息(时钟初始值为当前 时间,无需获取系统时间)。
时间: 2024-03-21 18:39:03 浏览: 18
好,我可以为您提供一个基本的思路和代码示例。首先,我们需要启用 TIM3 和串口功能,并初始化相应的 GPIO 端口。然后,我们可以设置 TIM3 的预分频和计数周期,使其每秒钟更新一次计数器。在 TIM3 的更新中断中,我们可以编写代码来更新时分秒的值,并将其发送到串口。以下是示例代码:
```c
#include "stm32f10x.h"
#include "stdio.h"
UART_HandleTypeDef huart;
TIM_HandleTypeDef htim3;
void SystemClock_Config(void);
static void MX_GPIO_Init(void);
static void MX_USART1_UART_Init(void);
static void MX_TIM3_Init(void);
int seconds = 0;
int minutes = 0;
int hours = 0;
int main(void)
{
HAL_Init();
SystemClock_Config();
MX_GPIO_Init();
MX_USART1_UART_Init();
MX_TIM3_Init();
HAL_TIM_Base_Start_IT(&htim3); // 启动定时器
while (1)
{
// 主循环中不需要执行任何操作
}
}
void HAL_TIM_PeriodElapsedCallback(TIM_HandleTypeDef *htim)
{
if (htim->Instance == TIM3) // 判断是否是 TIM3 的中断
{
seconds++; // 每秒钟更新一次秒数
if (seconds >= 60)
{
seconds = 0;
minutes++;
}
if (minutes >= 60)
{
minutes = 0;
hours++;
}
if (hours >= 24)
{
hours = 0;
}
char buffer[50];
sprintf(buffer, "Time: %02d:%02d:%02d\r\n", hours, minutes, seconds);
HAL_UART_Transmit(&huart, (uint8_t *)buffer, strlen(buffer), HAL_MAX_DELAY); // 发送串口数据
}
}
void SystemClock_Config(void)
{
RCC_OscInitTypeDef RCC_OscInitStruct;
RCC_ClkInitTypeDef RCC_ClkInitStruct;
RCC_PeriphCLKInitTypeDef PeriphClkInit;
RCC_OscInitStruct.OscillatorType = RCC_OSCILLATORTYPE_HSE;
RCC_OscInitStruct.HSEState = RCC_HSE_ON;
RCC_OscInitStruct.HSEPredivValue = RCC_HSE_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_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();
}
PeriphClkInit.PeriphClockSelection = RCC_PERIPHCLK_USART1;
PeriphClkInit.Usart1ClockSelection = RCC_USART1CLKSOURCE_PCLK1;
if (HAL_RCCEx_PeriphCLKConfig(&PeriphClkInit) != HAL_OK)
{
Error_Handler();
}
}
static void MX_USART1_UART_Init(void)
{
huart.Instance = USART1;
huart.Init.BaudRate = 115200;
huart.Init.WordLength = UART_WORDLENGTH_8B;
huart.Init.StopBits = UART_STOPBITS_1;
huart.Init.Parity = UART_PARITY_NONE;
huart.Init.Mode = UART_MODE_TX_RX;
huart.Init.HwFlowCtl = UART_HWCONTROL_NONE;
huart.Init.OverSampling = UART_OVERSAMPLING_16;
if (HAL_UART_Init(&huart) != HAL_OK)
{
Error_Handler();
}
}
static void MX_TIM3_Init(void)
{
TIM_ClockConfigTypeDef sClockSourceConfig = {0};
TIM_MasterConfigTypeDef sMasterConfig = {0};
htim3.Instance = TIM3;
htim3.Init.Prescaler = 7199; // 时钟频率为 72MHz,分频 7200,计数器频率为 10kHz
htim3.Init.CounterMode = TIM_COUNTERMODE_UP;
htim3.Init.Period = 9999; // 计数周期为 1s
htim3.Init.ClockDivision = TIM_CLOCKDIVISION_DIV1;
if (HAL_TIM_Base_Init(&htim3) != HAL_OK)
{
Error_Handler();
}
sClockSourceConfig.ClockSource = TIM_CLOCKSOURCE_INTERNAL;
if (HAL_TIM_ConfigClockSource(&htim3, &sClockSourceConfig) != HAL_OK)
{
Error_Handler();
}
sMasterConfig.MasterOutputTrigger = TIM_TRGO_RESET;
sMasterConfig.MasterSlaveMode = TIM_MASTERSLAVEMODE_DISABLE;
if (HAL_TIMEx_MasterConfigSynchronization(&htim3, &sMasterConfig) != HAL_OK)
{
Error_Handler();
}
}
static void MX_GPIO_Init(void)
{
__HAL_RCC_GPIOA_CLK_ENABLE();
GPIO_InitTypeDef GPIO_InitStruct = {0};
GPIO_InitStruct.Pin = GPIO_PIN_9;
GPIO_InitStruct.Mode = GPIO_MODE_AF_PP;
GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_HIGH;
HAL_GPIO_Init(GPIOA, &GPIO_InitStruct);
GPIO_InitStruct.Pin = GPIO_PIN_10;
GPIO_InitStruct.Mode = GPIO_MODE_INPUT;
GPIO_InitStruct.Pull = GPIO_NOPULL;
HAL_GPIO_Init(GPIOA, &GPIO_InitStruct);
}
void Error_Handler(void)
{
}
```
这个代码会在串口上每秒钟输出一次时间信息,格式为 "Time: HH:MM:SS"。您可以根据自己的需要修改输出格式和串口参数。