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LPC2294 How to program a counter

Hello everybody,

I have a Philips LPC2294/01 MC.

I would like to count the rise or falling edge from an external signal.

I have 2 questions and need your help!

1. Do my MC already have an external counter? I think so but I donÂ't reallyfound somethink about that.
2. And if not? How can I count an rise or falling edge with the internal timer/counter?

I hope somebody can help me? Maybe with some code to?

Thx!!!

Parents

0 Ingo Krusche over 16 years ago in reply to ImPer Westermark

Hi Per,

this is me again.

We can not really handle what you proposed us.

But we try to catch our interrupts with an external interrupt input. We get the increments from a magnetic sensor on a north/south magnetic line. (hope that is the right translation!!)
We want to try the counting with a slow speed. But our external interrupt doesnÂ't work.

here is the code

#include <stdio.h>
#include <LPC22XX.H>

#define VPBDIV_VAL  0x02

__irq void eint3 (void) {

  IOCLR0 = 0x00000100;
  EXTINT = 0x00000003;

  VICVectAddr = 0x0000000;
}
void init_extern(void)
{
        IODIR0 = 0x00000100;

  VPBDIV=0;
  EXTMODE = (1<<3);
  VPBDIV=VPBDIV_VAL;
  VPBDIV=0;
  EXTPOLAR = ~(1<<3);
  VPBDIV=VPBDIV_VAL;
  VICIntEnable = ( 1 << 17 );
  VICVectCntl2 = (0x20 | (1 <<17)) ;
  VICVectAddr2 = (unsigned)eint3;
  VICIntEnable = ( 1 << 17 );
}

int main (void)
{

        PINSEL1 |= (1<<29);
        PINSEL1 &=~ (1<<28);
        init_extern();

while (1)
        {

        }
}

this code shall only turn a LED on when an interrupt was detected on input P30.

What is wrong?

Maybe you or someone else can help us with it?

Thanks a lot!

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