pointers to functions

[Chris Burger]

Hello,

After sending my question about arguments to IntServRoutine and the positive response from the forum members (I like to thank you for that) I have developed my program further more.
In the book ‘PICmicro MCU C’ of Nigel Gardner I have found some information about passing pointers to Functions. On page 111 he is giving two examples. I have adopted the examples to my program and the first program with the & operator is working the second(with *) NOT.
Can anyone explain that?

#include <16f84.h>

void leesSchak(int &cnt, int &pnt)
{ cnt = 9;
if (INPUT(PIN_A3) == 1) // is pin_A3 1 -> pointl = 00
pnt = 0x00;
if (INPUT(PIN_A3) == 0)
pnt = 0x09; // is pin_A3 0 -> pointl = 09
}

void main(void)
{
leesSchak(count, point);
while(1)
{ }
}
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
// this one is NOT working correctly
void leesSchak(int *cnt, int *pnt)
{ *cnt = 9;
if (INPUT(PIN_A3) == 1) // is pin_A3 1 -> pnt = 00
*pnt = 0x00;
if (INPUT(PIN_A3) == 0)
*pnt = 0x09; // is pin_A3 0 -> pnt = 09
}

void main(void)
{
leesSchak(count, point);
while(1)
{ }
}
___________________________
This message was ported from CCS's old forum
Original Post ID: 144516296

[PCM programmer]

:=// this one is NOT working correctly
:=void leesSchak(int *cnt, int *pnt)
:={ *cnt = 9;
:= if (INPUT(PIN_A3) == 1) // is pin_A3 1 -> pnt = 00
:= *pnt = 0x00;
:= if (INPUT(PIN_A3) == 0)
:= *pnt = 0x09; // is pin_A3 0 -> pnt = 09
:=}
:=
:=void main(void)
:={

The function as declared, is expecting pointers to arguments,
but you're passing it values. You need to give it the
addresses of the values. Change it to be:
leesSchak(&count, &point);

:= leesSchak(count, point);
:=while(1)
:= { }
:= }
___________________________
This message was ported from CCS's old forum
Original Post ID: 144516297