how to detect the push button

[shir]

Hi..
I'm new in programming microcontroller in c. And I was given an assignment to write a simple program to turn 'ON' and "OFF' the LED by pressing push buttons. The microcontroller i'm using is PIC18F4620. And i'll need 1 LED and 2 push buttons to program this. I have already tried to write the program but it doesnt work. Here is my program:

#include <p18f4620.h>
 
#pragma config OSC = HS
#pragma config WDT = OFF
#pragma config LVP = OFF
 
#define btn_on        PORTBbits.RB4
#define btn_off        PORTBbits.RB5
#define led        PORTAbits.RA0
 
void press(void);
void on(void);
void off(void);
 
void main(void)
{
             TRISA = 0;                        //set Port A(LED) as output
             PORTAbits.RA0 = 0;        //reset LED
 
             while(btn_on != btn_off)        //wait for btn press
 
    if (btn_on = 1)        //btn on pressed
    on();
 
    if (btn_off = 1)    //btn off pressed
    off();
}
 
    void on(void)
    {
              while(!btn_on);        //wait for btn(RB4) released
              PORTAbits.RA0 = 0x0F;        //on LED
    }
 
    void off(void)
    {
              while(!btn_off);        //wait for btn(RB5) released
              PORTAbits.RA0 = 0x00;        //off LED
    }
 

the underline statement is the one i not sure whether is correct or not. I have being working on this for a week. But still cant get the program run correctly. Hope to get some guide. Thank.

[Peterwkc]

Can you explain a bit your code with comment ?

[ilikepython]

Hi..
I'm new in programming microcontroller in c. And I was given an assignment to write a simple program to turn 'ON' and "OFF' the LED by pressing push buttons. The microcontroller i'm using is PIC18F4620. And i'll need 1 LED and 2 push buttons to program this. I have already tried to write the program but it doesnt work. Here is my program:

#include <p18f4620.h>
 
#pragma config OSC = HS
#pragma config WDT = OFF
#pragma config LVP = OFF
 
#define btn_on        PORTBbits.RB4
#define btn_off        PORTBbits.RB5
#define led        PORTAbits.RA0
 
void press(void);
void on(void);
void off(void);
 
void main(void)
{
             TRISA = 0;                        //set Port A(LED) as output
             PORTAbits.RA0 = 0;        //reset LED
 
             while(btn_on != btn_off)        //wait for btn press
 
    if (btn_on = 1)        //btn on pressed
    on();
 
    if (btn_off = 1)    //btn off pressed
    off();
}
 
    void on(void)
    {
              while(!btn_on);        //wait for btn(RB4) released
              PORTAbits.RA0 = 0x0F;        //on LED
    }
 
    void off(void)
    {
              while(!btn_off);        //wait for btn(RB5) released
              PORTAbits.RA0 = 0x00;        //off LED
    }
 

the underline statement is the one i not sure whether is correct or not. I have being working on this for a week. But still cant get the program run correctly. Hope to get some guide. Thank.

Also, you have several errors in there. Do you mean something like this:

#include <p18f4620.h>
 
#pragma config OSC = HS
#pragma config WDT = OFF
#pragma config LVP = OFF
 
#define btn_on        PORTBbits.RB4
#define btn_off        PORTBbits.RB5
#define led        PORTAbits.RA0
 
void press(void);
void on(void);
void off(void);
 
void main(void)
{
    TRISA = 0;                        //set Port A(LED) as output
    PORTAbits.RA0 = 0;        //reset LED
 
    while(btn_on != btn_off)                  //wait for btn press
    {
        if (btn_on == 1)        //btn on pressed
            on();
 
        if (btn_off == 1)                   //btn off pressed
            off();
    }
}
 
 
void on(void)
{
    while(!btn_on)             //wait for btn(RB4) released
    {
        PORTAbits.RA0 = 0x0F;        //on LED
    }
}
 
void off(void)
{
    while(!btn_off)                                         //wait for btn(RB5) released
    {
        PORTAbits.RA0 = 0x00;        //off LED
    }
}
 

[shir]

i counldn't see much change..

[ilikepython]

i counldn't see much change..

I changed the "=" (assignement) to "==" (boolean equailty) and I added braces to your while loops. Also, I indented and put the code in code tags to make it easier to read.