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[SOLVED] PIC16F877 Input button not working properly

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WStevens_sa

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Hi all

My project is as follows. PICF877 programmed to be a RTC using TMR0 with prescaler for 1 second delay which displays day and time on a 2 x 16 LCD as "MON 00:00:00. RC0 sets hours which works and RC1 is supposed to set the minutes but does not work.

Where have I gone wrong. RC1 is not triggering "if (Button(&PORTC, 1, 1, 1)) "

// LCD module connections
sbit LCD_RS at RB4_bit;
sbit LCD_EN at RB5_bit;
sbit LCD_D4 at RB0_bit;
sbit LCD_D5 at RB1_bit;
sbit LCD_D6 at RB2_bit;
sbit LCD_D7 at RB3_bit;
sbit LCD_RS_Direction at TRISB4_bit;
sbit LCD_EN_Direction at TRISB5_bit;
sbit LCD_D4_Direction at TRISB0_bit;
sbit LCD_D5_Direction at TRISB1_bit;
sbit LCD_D6_Direction at TRISB2_bit;
sbit LCD_D7_Direction at TRISB3_bit;

// VARIABLES FOR LCD

char* txt1;
int count;
int shiftcount=0;
int tic = 0;
int msec=0;
int timer_set = 0;


// INTERRUPT VARIABLES
unsigned int counter = 0 ;
unsigned int seconds = 0, minutes = 0, hours = 0, days = 0;
char* weekdays[7] = {"MON","TUE","WED","THU","FRI","SAT","SUN"};

// INTERRUPT RTC
void interrupt(void) {

if(T0IF_bit == 1){ // Check for interrupt flag

T0IF_bit=0; //Reset flag
counter++ ;
if(counter > 15625){ // 1 sec 16 Mhz crystal = 16000000 / 4 / 256 =15625
counter = 0 ;
seconds++ ;
if(seconds == 60){
seconds = 0 ;
minutes++ ;
if(minutes == 60){
minutes = 0 ;
hours++ ;
if(hours == 24){
hours = 0 ;
days++;
if (days == 7){
days = 0;
}
}
}
}
}
}
}

void main(){
//LCD
Lcd_Init(); // Initialize LCD
Lcd_Cmd(_LCD_CLEAR); // Clear display
Lcd_Cmd(_LCD_CURSOR_OFF); // Cursor off

Lcd_out(1,7,":");
Lcd_out(1,10,":");

//TMR0
OPTION_REG = 8;
GIE_bit = 1; //Enable Global Interrupt
T0IF_bit = 0; //Clear interrupt flag
T0IE_bit = 1; //Enable TMR0 interrupt
PEIE_bit = 1; //Peripheral Interrupt Enable bit

//PUSH BUTTON SETTINGs
TRISA = 0; //PortA all outputs
PORTA = 0;
TRISC = 1; // Configure PORTC as inputs
PORTC = 0; // Initial PORTC value


// Lcd_Chr(1,1,48+9); // // Only from 0 to 9. Need to use shift registerto

while(1){
//SECONDS
Lcd_Chr(1,12,48+(seconds % 10)); // seconds counter LSB
Lcd_Chr(1,11,48+((seconds /10) % 10)); //Seconds counter MSB

//MINUTES
Lcd_Chr(1,9,48+(minutes % 10)); // minutes counter LSB
Lcd_Chr(1,8,48+((minutes /10) % 10)); //minutes counter MSB

//HOURS
Lcd_Chr(1,6,48+(hours % 10)); // hours counter LSB
Lcd_Chr(1,5,48+((hours /10) % 10)); // hours counter MSB

//DAYS
Lcd_out(1,1,weekdays[days]); // days of the week

//PUSHBUTTON INPUT HOURS RC0_BIT
if (Button(&PORTC, 0, 1, 1)) {
hours++;
Delay_ms(100); // Adjust counting time when button depressed
if (hours ==24) {hours=0;}
}

//PUSHBUTTON INPUT MINUTES RC1_BIT
if (Button(&PORTC, 1, 1, 1)) {
minutes++;
Delay_ms(100); // Adjust counting time when button depressed
if (minutes ==60) {minutes=0;}
}

}
}
Click to expand...
 

Hi;

Modify this line
TRISC = 1; // Configure PORTC as inputs
// this configures only PORTC.0 as input

to
TRISC = 3; // Configure PORTC.0 and PORTC.1 as inputs
 
check this sample code may b it will help you.....it is for mikro c compiler u can check on the simulator......i hpe this willl be helpful to you..
Code: 
bit oldstate;                                    // Old state flag

void main() {

  ANSEL  = 0;                                    // Configure AN pins as digital I/O
  ANSELH = 0;
  C1ON_bit = 0;                                  // Disable comparators
  C2ON_bit = 0;

  TRISB0_bit = 1;                                // set RB0 pin as input
  
  TRISC = 0x00;                                  // Configure PORTC as output
  PORTC = 0xAA;                                  // Initial PORTC value
  oldstate = 0;
  
  do {
    if (Button(&PORTB, 0, 1, 1)) {               // Detect logical one
      oldstate = 1;                              // Update flag
    }
    if (oldstate && Button(&PORTB, 0, 1, 0)) {   // Detect one-to-zero transition
      PORTC = ~PORTC;                            // Invert PORTC
      oldstate = 0;                              // Update flag
    }
  } while(1);                                    // Endless loop
}
 
Okay. I understand now. The port set for inputs works accordingly.

TRISC = 5 which is binary 101

RC0 = 1
RC1 = 0
RC2 = 1
RC3 = 0
RC4 = 0
RC5 = 0
RC6 = 0
RC7 = 0

So only RC0 and RC2 will allow inputs.
 

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