Hello, i'm trying to do a period measure using pca. I tried to write some code but it doesn't work, i don't know what's wrong.

thank you very much if somebody could help me

Raffaele



unsigned int lettura, prevlettura1,period;

void pca_isr() interrupt 6 using 1
{
if (CCF0)
{
lettura = (CCAP0H<<8) + CCAP0L;
period = lettura - prevlettura1;
prevlettura1=lettura;
CCF0=0;
}
}

void pca_init()
{
EA=1;
CCON = 0x00;
CMOD = 0x00;
CH = 0x00;
CL = 0x00;
CCAPM0 = 0x21;
CCON = 0x40;
EC=1;
}