STM32实战 2.矩阵键盘通过串口3输出

#include "KEY44.h"

#include "sys.h"

#include "delay.h"

#include "usart.h"

u8 key_num = 0;

int main(void)

{

uart_init(115200);

delay_init();

KEY44_Init();

while(1)

{

key_num = key44_Scan();

if(key_num != 0)

{

printf("KEY is %drn",key_num);

}

}

}

#include "KEY44.h"

#include "sys.h"

#include "delay.h"

void  KEY44_Init(void)

{

GPIO_InitTypeDef GPIO_InitStructure;

RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA,ENABLE);

GPIO_InitStructure.GPIO_Pin = GPIO_Pin_0 |GPIO_Pin_1 |GPIO_Pin_2 |GPIO_Pin_3;

GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;

GPIO_InitStructure.GPIO_Mode = GPIO_Mode_Out_PP;

GPIO_Init(GPIOA, &GPIO_InitStructure);

GPIO_InitStructure.GPIO_Pin = GPIO_Pin_4 |GPIO_Pin_5 |GPIO_Pin_6 |GPIO_Pin_7;

GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;

GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IPU;

GPIO_Init(GPIOA, &GPIO_InitStructure);

}

unsigned char key44_Scan(void)

{

H_1 = 0;

H_2 = 1;

H_3 = 1;

H_4 = 1;

if( L_1 == 0)

{

delay_ms(10);

if(L_1 == 0)

{

while(!L_1);

return 1;

}

}

if(L_2 == 0)

{

delay_ms(10);

if(L_2 == 0)

{

while(!L_2);

return 2;

}

}

if(L_3 == 0)

{

delay_ms(10);

if(L_3 == 0)

{

while(!L_3);

return 3;

}

}

if(L_4 == 0)

{

delay_ms(10);

if(L_4 == 0)

{

while(!L_4);

return 4;

}

}

H_1 = 1;

H_2 = 0;

H_3 = 1;

H_4 = 1;

if(L_1 == 0)

{

delay_ms(10);

if(L_1 == 0)

{

while(!L_1);

return 5;

}

}

if(L_2 == 0)

{

delay_ms(10);

if(L_2 == 0)

{

while(!L_2);

return 6;

}

}

if(L_3 == 0)

{

delay_ms(10);

if(L_3 == 0)

{

while(!L_3);

return 7;

}

}

if(L_4 == 0)

{

delay_ms(10);

if(L_4 == 0)

{

while(!L_4);

return 8;

}

}

H_1 = 1;

H_2 = 1;

H_3 = 0;

H_4 = 1;

if(L_1 == 0)

{

delay_ms(10);

if(L_1 == 0)

{

while(!L_1);

return 9;

}

}

if(L_2 == 0)

{

delay_ms(10);

if(L_2 == 0)

{

while(!L_2);

return 10;

}

}

if(L_3 == 0)

{

delay_ms(10);

if(L_3 == 0)

{

while(!L_3);

return 11;

}

}

if(L_4 == 0)

{

delay_ms(10);

if(L_4 == 0)

{

while(!L_4);

return 12;

}

}

H_1 = 1;

H_2 = 1;

H_3 = 1;

H_4 = 0;

if(L_1 == 0)

{

delay_ms(10);

if(L_1 == 0)

{

while(!L_1);

return 13;

}

}

if(L_2 == 0)

{

delay_ms(10);

if(L_2 == 0)

{

while(!L_2);

return 14;

}

}

if(L_3 == 0)

{

delay_ms(10);

if(L_3 == 0)

{

while(!L_3);

return 15;

}

}

if(L_4 == 0)

{

delay_ms(10);

if(L_4 == 0)

{

while(!L_4);

return 16;

}

}

return 0;

}

#ifndef __KEY44_H

#define __KEY44_H  

//PA0~PA3为推挽式输出

//PA4~PA7为上拉式输入

#define H_1 PAout(0)

#define H_2 PAout(1)

#define H_3 PAout(2)

#define H_4 PAout(3)

#define L_1 PAin(4)

#define L_2 PAin(5)

#define L_3 PAin(6)

#define L_4 PAin(7)

void  KEY44_Init(void);

unsigned char key44_Scan(void);     

#endif