stm32f103 5*4键盘 代码

以下是一个使用STM32F103 MCU的5x4键盘代码示例，它使用了GPIO库和定时器库。

#include "stm32f10x.h"
#include "stm32f10x_gpio.h"
#include "stm32f10x_tim.h"

#define ROWS 5
#define COLS 4

GPIO_InitTypeDef GPIO_InitStructure;

GPIO_TypeDef* rowPorts[ROWS] = {GPIOA, GPIOA, GPIOA, GPIOA, GPIOA};
uint16_t rowPins[ROWS] = {GPIO_Pin_0, GPIO_Pin_1, GPIO_Pin_2, GPIO_Pin_3, GPIO_Pin_4};

GPIO_TypeDef* colPorts[COLS] = {GPIOB, GPIOB, GPIOB, GPIOB};
uint16_t colPins[COLS] = {GPIO_Pin_12, GPIO_Pin_13, GPIO_Pin_14, GPIO_Pin_15};

uint8_t keys[ROWS][COLS] = {
    {'1', '2', '3', 'A'},
    {'4', '5', '6', 'B'},
    {'7', '8', '9', 'C'},
    {'*', '0', '#', 'D'},
    {'X', 'X', 'X', 'X'}
};

void scanKeys() {
    int i, j;
    for(i = 0; i < ROWS; i++) {
        GPIO_ResetBits(rowPorts[i], rowPins[i]);
        for(j = 0; j < COLS; j++) {
            if(GPIO_ReadInputDataBit(colPorts[j], colPins[j]) == RESET) {
                // key pressed
                printf("%c pressed\n", keys[i][j]);
                while(GPIO_ReadInputDataBit(colPorts[j], colPins[j]) == RESET);
            }
        }
        GPIO_SetBits(rowPorts[i], rowPins[i]);
    }
}

void initGPIO() {
    int i;
    RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA | RCC_APB2Periph_GPIOB, ENABLE);
    for(i = 0; i < ROWS; i++) {
        GPIO_InitStructure.GPIO_Pin = rowPins[i];
        GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
        GPIO_InitStructure.GPIO_Mode = GPIO_Mode_Out_PP;
        GPIO_Init(rowPorts[i], &GPIO_InitStructure);
        GPIO_SetBits(rowPorts[i], rowPins[i]);
    }
    for(i = 0; i < COLS; i++) {
        GPIO_InitStructure.GPIO_Pin = colPins[i];
        GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
        GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IPU;
        GPIO_Init(colPorts[i], &GPIO_InitStructure);
    }
}

void initTimer() {
    TIM_TimeBaseInitTypeDef TIM_TimeBaseStructure;
    RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM4, ENABLE);
    TIM_TimeBaseStructure.TIM_Period = 999;
    TIM_TimeBaseStructure.TIM_Prescaler = 7199;
    TIM_TimeBaseStructure.TIM_ClockDivision = 0;
    TIM_TimeBaseStructure.TIM_CounterMode = TIM_CounterMode_Up;
    TIM_TimeBaseInit(TIM4, &TIM_TimeBaseStructure);
    TIM_Cmd(TIM4, ENABLE);
    TIM_ITConfig(TIM4, TIM_IT_Update, ENABLE);
}

int main(void) {
    initGPIO();
    initTimer();
    while(1) {
    }
}

void TIM4_IRQHandler(void) {
    if(TIM_GetITStatus(TIM4, TIM_IT_Update) != RESET) {
        scanKeys();
        TIM_ClearITPendingBit(TIM4, TIM_IT_Update);
    }
}

这个简单的示例代码可用于5x4矩阵键盘扫描。它使用了定时器中断来周期性地扫描键盘，并在控制台上输出按下的键。你可以根据自己的需求修改keys数组以匹配你的键盘布局。