以STM32单片机为核心,设计一个数码管显示的四位计数器,键盘有“加1”、“减1”和“清零”三个按键,键操作功能定义为:每按一次“加1”键,显示器显示数值增1,每按一次“加1”键,显示器显示数值增1,至9999再回0;每按一次“减1”键,显示器显示数值减1,至0再回9999;每按一次“清零”键,显示器显示数值清零
时间: 2024-03-26 08:38:18 浏览: 79
按键控制数码管实现显示数值加减
这个数码管计数器可以用STM32单片机的GPIO口来控制数码管的显示,用按键来实现功能选择和数值修改。以下是一个基本的参考设计:
1. 硬件设计
数码管计数器使用四个共阳数码管。数码管的控制使用STM32的GPIO口,连接到数码管的A、B、C、D、E、F、G、DP8个引脚。按键使用三个开关,一个接GND,一个接VCC,一个接到GPIO口,用于检测按下状态。输入端口需要加上上拉电阻,以确保输入的高低电平的正确性。
2. 软件设计
使用STM32单片机的GPIO口控制数码管的显示,使用定时器中断来实现数码管的扫描。在定时器中断中,按照计数器的值,将对应的数码管的8个引脚设置为高低电平,以实现数码管的显示。
按键检测可以使用GPIO口的外部中断来实现。在按键按下时触发外部中断,根据按键的类型,修改计数器的值,并在数码管上显示出来。
3. 代码实现
以下是一个基本的代码框架,仅供参考:
```c
#include "stm32f10x.h"
#define KEY_PLUS GPIO_Pin_0
#define KEY_MINUS GPIO_Pin_1
#define KEY_CLEAR GPIO_Pin_2
void GPIO_Configuration(void)
{
GPIO_InitTypeDef GPIO_InitStructure;
// 数码管控制口
RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA, ENABLE);
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_0 | GPIO_Pin_1 | GPIO_Pin_2 | GPIO_Pin_3 | GPIO_Pin_4 | GPIO_Pin_5 | GPIO_Pin_6 | GPIO_Pin_7;
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_Out_PP;
GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
GPIO_Init(GPIOA, &GPIO_InitStructure);
// 按键输入口
RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOB, ENABLE);
GPIO_InitStructure.GPIO_Pin = KEY_PLUS | KEY_MINUS | KEY_CLEAR;
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IPU;
GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
GPIO_Init(GPIOB, &GPIO_InitStructure);
}
void TIM_Configuration(void)
{
TIM_TimeBaseInitTypeDef TIM_TimeBaseStructure;
NVIC_InitTypeDef NVIC_InitStructure;
// 定时器中断
RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM2, ENABLE);
TIM_TimeBaseStructure.TIM_Period = 999;
TIM_TimeBaseStructure.TIM_Prescaler = 7199;
TIM_TimeBaseStructure.TIM_ClockDivision = TIM_CKD_DIV1;
TIM_TimeBaseStructure.TIM_CounterMode = TIM_CounterMode_Up;
TIM_TimeBaseInit(TIM2, &TIM_TimeBaseStructure);
TIM_ITConfig(TIM2, TIM_IT_Update, ENABLE);
TIM_Cmd(TIM2, ENABLE);
NVIC_InitStructure.NVIC_IRQChannel = TIM2_IRQn;
NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 0;
NVIC_InitStructure.NVIC_IRQChannelSubPriority = 1;
NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
NVIC_Init(&NVIC_InitStructure);
}
void EXTI_Configuration(void)
{
EXTI_InitTypeDef EXTI_InitStructure;
NVIC_InitTypeDef NVIC_InitStructure;
// 外部中断
RCC_APB2PeriphClockCmd(RCC_APB2Periph_AFIO, ENABLE);
GPIO_EXTILineConfig(GPIO_PortSourceGPIOB, GPIO_PinSource0);
GPIO_EXTILineConfig(GPIO_PortSourceGPIOB, GPIO_PinSource1);
GPIO_EXTILineConfig(GPIO_PortSourceGPIOB, GPIO_PinSource2);
EXTI_InitStructure.EXTI_Line = EXTI_Line0 | EXTI_Line1 | EXTI_Line2;
EXTI_InitStructure.EXTI_Mode = EXTI_Mode_Interrupt;
EXTI_InitStructure.EXTI_Trigger = EXTI_Trigger_Falling;
EXTI_InitStructure.EXTI_LineCmd = ENABLE;
EXTI_Init(&EXTI_InitStructure);
NVIC_InitStructure.NVIC_IRQChannel = EXTI0_IRQn;
NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 0;
NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0;
NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
NVIC_Init(&NVIC_InitStructure);
NVIC_InitStructure.NVIC_IRQChannel = EXTI1_IRQn;
NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 0;
NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0;
NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
NVIC_Init(&NVIC_InitStructure);
NVIC_InitStructure.NVIC_IRQChannel = EXTI2_IRQn;
NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 0;
NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0;
NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
NVIC_Init(&NVIC_InitStructure);
}
void TIM2_IRQHandler(void)
{
static unsigned int cnt = 0;
TIM_ClearITPendingBit(TIM2, TIM_IT_Update);
// 数码管扫描
// 根据计数器的值,设置数码管的8个引脚的电平
// ...
cnt++;
if (cnt >= 100) {
cnt = 0;
// 计数器加1
// 如果计数器为9999,则清零
// ...
}
}
void EXTI0_IRQHandler(void)
{
EXTI_ClearITPendingBit(EXTI_Line0);
// 按键加1
// ...
}
void EXTI1_IRQHandler(void)
{
EXTI_ClearITPendingBit(EXTI_Line1);
// 按键减1
// ...
}
void EXTI2_IRQHandler(void)
{
EXTI_ClearITPendingBit(EXTI_Line2);
// 按键清零
// ...
}
int main(void)
{
GPIO_Configuration();
TIM_Configuration();
EXTI_Configuration();
while(1) {
}
}
```
以上代码仅是一个基本的框架,具体的实现需要根据实际的硬件和需求来进行修改和完善。
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