Small problem in MikroC ( LCD clock)

[BGAmodz]

Hello every one here in the board .

During the past days , i have been learning how to set up programs to run them on Microcontrolers like the PICxxFxx .
Now i am working on making a small ajustable electronic clock using the PIC16F84A but i have some minor problems ; for example i have a variable s1 that goes from 0 to 9 and goes back to 0 in a loop ; but on my case if the variable goes from 0 to 9 , i have 012345679:1...........
i got ':' in place of 0 .

i should get ....901.............

here is the program :

sbit LCD_RS at RB1_bit;
sbit LCD_EN at RB2_bit;
sbit LCD_D7 at RB6_bit;
sbit LCD_D6 at RB5_bit;
sbit LCD_D5 at RB4_bit;
sbit LCD_D4 at RB3_bit;


sbit LCD_RS_Direction at TRISB1_bit;
sbit LCD_EN_Direction at TRISB2_bit;
sbit LCD_D7_Direction at TRISB6_bit;
sbit LCD_D6_Direction at TRISB5_bit;
sbit LCD_D5_Direction at TRISB4_bit;
sbit LCD_D4_Direction at TRISB3_bit;


char s1,s2,m1,m2,h1,h2,p,j;



void main() {
Lcd_Init();
Lcd_cmd(_lcd_cursor_off);
s1=s2=m1=m2=h1=h2=48;
p=58;
lcd_chr(1,6,p);  lcd_chr(1,3,p);
lcd_chr(1,8,s1); lcd_chr(1,7,s2);
lcd_chr(1,5,m1); lcd_chr(1,4,m2);
lcd_chr(1,2,h1); lcd_chr(1,1,h2);
for(;;){

s1++;
delay_ms(1000);
lcd_chr(1,6,p);  lcd_chr(1,3,p);
lcd_chr(1,8,s1); lcd_chr(1,7,s2);
lcd_chr(1,5,m1); lcd_chr(1,4,m2);
lcd_chr(1,2,h1); lcd_chr(1,1,h2);
if (s1==58){s1=48;s2++;}
if (s2==54){s1=s2=48;m1++;}
if (m1==58){s1=s2=m1=48;m2++;}
if (m2==54){s1=s2=m1=m2=48;h1++;}
if (h1==58){s1=s2=m1=m2=h1=48;h2++;}
if (h2==50){s1=s2=m1=m2=h1=h2=48;}

}
}

 

[misterT]

ASCII 48 is the character '0'
ASCII 49 is the character '1'
...
ASCII 57 is the character '9'
ASCII 58 is the character ':'

At the moment you check if s1==58
When you check for that value, you have already displayed it, because the IF statement is after the lcd commands.
Then you set s1=48, which is the character '0', but, at the beginning of the loop you add 1 to the value. So the next character displayed is '1'.

 

[tunedwolf]

Beat me to it

Your logic is wrong, as Mister T mentioned, you are setting/ manipulating your variables after you have already displayed them. I also don't think that you are handling your rollover from 23:59 properly.

My apologies, after re-reading it, and thinking about it for a minute I realised that you are displaying a 12hr format. I'm so used to working in 24hr format I didn't even notice!

 

[misterT]

Try:

for(;;) {
    delay_ms(1000);

    s1++;

    if (s1==58){s1=48;s2++;}
    if (s2==54){s1=s2=48;m1++;}
    if (m1==58){s1=s2=m1=48;m2++;}
    if (m2==54){s1=s2=m1=m2=48;h1++;}
    if (h1==58){s1=s2=m1=m2=h1=48;h2++;}
    if (h2==50){s1=s2=m1=m2=h1=h2=48;}

    lcd_chr(1,6,p);  lcd_chr(1,3,p);
    lcd_chr(1,8,s1); lcd_chr(1,7,s2);
    lcd_chr(1,5,m1); lcd_chr(1,4,m2);
    lcd_chr(1,2,h1); lcd_chr(1,1,h2);
}

EDIT: This should at least fix the problem with "s1". I did not track the other variables.. there may be problems with them (or not).

 

[BGAmodz]

ASCII 48 is the character '0'
ASCII 49 is the character '1'
...
ASCII 57 is the character '9'
ASCII 58 is the character ':'

At the moment you check if s1==58
When you check for that value, you have already displayed it, because the IF statement is after the lcd commands.
Then you set s1=48, which is the character '0', but, at the beginning of the loop you add 1 to the value. So the next character displayed is '1'.

As you can see on the program i have s1 incremented from 0 and forward , when this variable reaches 10 it should be transformed to 0 then 1 and so on.

 

[misterT]

Yes, we got the problem.
Did you try my solution? Move the LCD commands after the IF statements. I think it should work.

 

[BGAmodz]

Hey mate it worked but why it doesn't work the way i ve planed it ??

 

[misterT]

Posts #2 and #3 explains it.. I don't know how to explain it better than that. Just carefully think about what the code does.. step-by-step.

 

[BGAmodz]

Hey thanks for the help , now i understand , i should have put the s++ right before the conditions .

 

[misterT]

Yes. That is very good style. Always validate values immediately after you change them.

 

[BGAmodz]

Yes. That is very good style. Always validate values immediately after you change them.

Thanks , everything is good now .