Subs and functions in C

[be80be]

Been playing with C for awhile. Its a little bit of a change any way. Whats the right way to write a Sub in C

 

[Sceadwian]

https://en.wikipedia.org/wiki/Subroutine
Write tight code. Meaning determine what the code you're writing is actually doing, and tweak it so that it does it better.

 

[be80be]

Nice thanks I was thinking more like this C uses functions as both unlike my beloved Basic.

void send_data(unsigned char data_out)
{
unsigned char i;
i=8;
while (i)
{
data_out = data_out >>1;
i--;
SClock =~ SClock;
}
}

 

[Sceadwian]

There is no 'right' way, it's just the ways that work efficiently.

 

[Pommie]

A basic sub is just a function that doesn't return anything. So your void send_data(unsigned char data_out) is equivalent to a sub.

Mike.

 

[be80be]

Well I been playing with MikroC and read dang near there whole help file and couldn't fine a thing to point me right. But i think I'm on the right track now
I wrote that piece and complied it and it said that main was a empty sub. Lol it was . Thanks Mike And Sceadwian

Now all i need is to figure how to do a bound In C

Like Send out 0b10101010 out A GPIO.B0 one bit at a time

int i;
 i=8;
  while (i)   
{
    GPIO.B0 = data>>1;
      i--;
       SClock=~SClock;
  }

 

[Pommie]

A for loop will do that for you,

    for(i=0;i<8;i++){           //for 0 to 7
        GPIO.B0 = data&1;       //send out bit zero
        data>>=1;               //shift data right 1 bit
        SClock=~SClock;         //doesn't this need to be 1 then 0
     }

Edit, what do you mean by Bound?

Mike.

 

[be80be]

Bound just lets you set it to what your sending so you don't have to set 0 to7 it would 0 bound to Data and it's size. Thanks Mike I feel like a real dummy I should of thought about a for loop.

I for loop would work great seeing I can't send more then 8 bits at a time. Thanks agin Mike.

 

[Ian Rogers]

You can if you specify a size

void shiftit( long value, int size)
   {
   while(size--)
      GPIO.B0 = (value >>= 1) & 1;
   }

Sorry if this looks a little compressed, but its only a suggestion.

 

[dougy83]

GPIO.B0 = (value >>= 1) & 1;

Wouldn't the (value >>= 1) be evaluated first, thereby loosing the first bit? (and adding a trailing '0')

 

[Ian Rogers]

Correct!! This isn't his solution, its only a suggestion I was merely showing the code in a while statement..

It's easy enough to split the line..

 

[be80be]

Dang the joy of a New compiler reserve words I new i wasn't that dumb data is a reserve word. My code worked Mikes code works and now it back to doing something useful. I'll post the whole thing when I get done it's a two wire LCD.

 

[Mr RB]

That is a pain for sure, the old MikroC allowed data as a variable name, but the new MikroC PRO won't allow data as a variable name.

 

[be80be]

Yep I got the idea i could use data as a variable from your site MrRB.I it worked before but I'm using the 4.80 beta. Funny how simple things seem to get me LOL

I slapped this baby in a nice do loop so it would row along and so far so good

#define  SClock GPIO.B1
unsigned char Sdata;
unsigned char i;
void main() {
OSCCON = 0x72;
TRISIO = 0b00000000;
CMCON0 = 7;   // no comparator
ANSEL = 0x00;

  do {
       Sdata =0b01010001;

        for(i=0;i<8;i++){           //for 0 to 7
        SClock=0;
        GPIO.B0 = Sdata&1;       //send out bit zero
        Sdata>>=1;               //shift data right 1 bit
        asm nop;
        SClock=1;         //doesn't this need to be 1 then 0
         }
    } while (1);

}

It shifts out nice

 

[Mr RB]

Yep I got the idea i could use data as a variable from your site MrRB.I it worked before but I'm using the 4.80 beta.
...

Whoops! Thanks for the heads up! I will edit that page and change the variable name "data" to "sdata" or something that will work with the new compiler.