Button-LED

Use the IO port query method to realize the key control of the LED's light on and off

#include "s3c24xx.h"

#define LED_ON 0

#define LED_OFF 1

#define KEY1_POS (0) //The position of key 1 on the IO port. Here it is GPF0 port, so the value is 0

#define KEY2_POS (2) //The position of key 2 in the IO port, here is GPF2 port, the value is

#define KEY3_POS (3)//GPG3   EINT11

#define LED1_POS (1<<4) //The position of LED1 in the IO port, here is GPF4 port, so the value is 4

#define LED2_POS (1<<5) //LED2 is located at the IO port, here is GPF5 port, the value is

#define LED3_POS (1<<6)     //GPF6

//Software related, not related to hardware buffe

#define OFS_KEY1 (0) //The state of key 1 is saved in the variable, here it is saved in the 0th position of the variable

#define OFS_KEY2 (1)// 

#define OFS_KEY3 (2)

#define GPF4_out (1<<(4*2)) //Set the 8th and 9th bits of GPFCON, that is, set the GPF4 bit output

#define GPF5_out (1<<(5*2)) //Set the 10th and 11th bits of GPFCON, that is, set the GPF5 bit output

#define GPF6_out (1<<(6*2)) //Set the 12th and 13th bits of GPFCON, that is, set the GPF6 bit output

#define GPF7_out (1<<(7*2))

#define hrdReadKey1 ((GPFDAT>>KEY1_POS)&0X01) //Read the status of key 1 

#define hrdReadKey2 ((GPFDAT>>KEY2_POS)&0X01) //Read the status of key 2 

#define hrdReadKey3 ((GPGDAT>>KEY3_POS)&0X01) //Read the status of key 2

#define hrdLed1On (GPFDAT &= (~LED1_POS)) // Make GPF4 output 0

#define hrdLed1Off (GPFDAT |= (LED1_POS)) // Make GPF4 output 1

#define hrdLed2On (GPFDAT &= (~LED2_POS)) // Make GPF5 output 0

#define hrdLed2Off (GPFDAT |= (LED2_POS)) // Make GPF5 output 1

#define hrdLed3On (GPGDAT &= (~LED3_POS)) // Make GPG6 output 0

#define hrdLed3Off (GPGDAT |= (LED3_POS)) // Make GPG6 output 1

typedef union

{

unsigned long byte;

struct

{

unsigned long key1 :1;

unsigned long key2 :1;

unsigned long key3 :1;

unsigned long notused :5;

}bits;

}mmiFlag_t;

mmiFlag_t mmiFlag;

#define mmiFlag_Key1 mmiFlag.bits.key1 //Judge whether it is the first time to process after the key is pressed

#define mmiFlag_Key2 mmiFlag.bits.key2 //Judge whether it is the first time to process after the key is pressed

#define mmiFlag_Key3 mmiFlag.bits.key3 //Judge whether it is the first time to process after the key is pressed

typedef union

{

unsigned long byte;

struct

{

unsigned long led1 :1;

unsigned long led2 :1;

unsigned long led3 :1;

unsigned long notused :5;

}bits;

}ledStatus_t;

ledStatus_t ledStatus;

#define led1Status    ledStatus.bits.led1

#define led2Status    ledStatus.bits.led2

#define led3Status ledStatus.bits.led3

volatile unsigned long dgtInBuf=1; //Save the switch input status

volatile unsigned long dgtInPre; //Pre-store switch input status

volatile unsigned long dgtCount; //delay count of switch input

// Initialize IO port

void ioInitialize_IO(void)

{

GPFCON |= GPF4_out; // Set GPF4, GPF5, GPF6 as output ports, bit [9:8] = 0b01

GPFCON &=(~GPF5_out);

GPFCON |= GPF5_out;

GPFCON |= GPF6_out;  

  GPFDAT = 0x00000000; //GPF4 outputs 0, LED1 lights up

}

//Refresh the IO port, read or write the IO port operation here

void ioRefresh_IO(void)

{

unsigned long buf=0;

if(hrdReadKey1==0) //Read the input status of key 1

buf |= (1< else if(hrdReadKey2==0)

buf |=  (1< else if(hrdReadKey3==0)

buf |=  (1< dgtInBuf = buf; //Save the read key status to dgtInBuf

}

/*Delay*/

void wait(unsigned long dly)

{

for(;dly>0;dly--);

}

/*

    *******************************Key processing function*********************************************

    This is achieved by querying the IO port, not interrupting it.

*/

void mmiProcess_Key1(void)

{

//mmiFlag_Key1 determines whether the key is pressed for the first time, and does not determine whether it is pressed next time until it is released

if((dgtInBuf&(1< {

mmiFlag_Key1 = 1; //The flag is set to 1 to prevent the key from being released and entering this judgment body again

if(led1Status==0) ​​//LED light status flip

{

led1Status = 1;

hrdLed1Off;

}

else

{

led1Status = 0;

hrdLed1On;

}

}

else if((dgtInBuf&(1< {

mmiFlag_Key1 = 0; //Set the flag to 0 and wait for the next key press

}

}

void mmiProcess_Key2(void)

{

//mmiFlag_Key2 determines whether the key is pressed for the first time, and does not determine whether it is pressed next time until it is released

if((dgtInBuf&(1< {

mmiFlag_Key2 = 1; //The flag is set to 1 to prevent the key from being released and entering this judgment body again

if(led2Status==0) ​​//LED light status flip

{

led2Status = 1;

hrdLed2Off;

}

else

{

led2Status = 0;

hrdLed2On;

}

}

else if((dgtInBuf&(1< {

mmiFlag_Key2 = 0; //Set the flag to 0 and wait for the next key press

}

}

void mmiProcess_Key3(void)

{

//mmiFlag_Key3 determines whether the key is pressed for the first time, and does not determine whether it is pressed next time until it is released

if((dgtInBuf&(1< {

mmiFlag_Key3 = 1; //The flag is set to 1 to prevent the key from being released and entering this judgment body again

if(led3Status==0) ​​//LED light status flip

{

led3Status = 1;

hrdLed3Off;

}

else

{

led3Status = 0;

hrdLed3On;

}

}

else if((dgtInBuf&(1< {

mmiFlag_Key3 = 0; //Set the flag to 0 and wait for the next key press

}

}

void mmiHandle_MMI(void)

{

if(dgtInBuf!=dgtInPre)//Judge whether the key input status is consistent with the last time

{

dgtInPre = dgtInBuf; //Assign this state to the Pre variable

dgtCount = 0; //Count cleared to 0

}

else //If the key input status is the same as last time

{

dgtCount++; // count plus 1

if(dgtCount>=5) //A delay of 5*1ms=5ms is performed. If the status is consistent for 5 times in a row, the input is considered valid.

{

dgtCount = 0;

mmiProcess_Key1();

mmiProcess_Key2();

mmiProcess_Key3();

}

}

}

int main()

{

ioInitialize_IO();

for(;;)

{

wait(1000); // 1ms delay

ioRefresh_IO();

mmiHandle_MMI();

}

  return 0;

}