hello
I am bit confuse about the period. How can we generate 50micro second period using CAPCOM2 in XC164CS? Can anyone hwlp me plz?
I just want to produce 50micro second period PWM or u can say 20Khz. What should be the timer reload value?
Vivek
Come back with some code you have written and: - what hardware you are running it on - what timer constants you have been using - how you computed your timer constants - what frequency you expected - what result (frequency or other result) you really got
Then someone on this forum will be able to help you by pointing out what you did wrong.
hi
I have provide my code here. It just produce the fix pulse width of 20 KHz. Now I want to change the pulse width but keep the frequency as 20KHz. I know here I provided on and off time and i can change that one to vary the width but some more flexibility so do I need to generate the another interuupt.
Cv1 and CV2 are the two registers values to compare
#include<XC164.h>
#include <stdio.h> /* standard I/O .h-file */
#define Period 0x007D /* 50u second */
#define cv1 0x003E /* TON*/ #define cv2 0x007D /* Toff*/
void CC16_event(void) interrupt 0x30{
if (CC2_CC16 == (int)cv1) { CC2_CC16 = cv2; } else { CC2_CC16 = cv1; } } void main (void) { DP9 |=0x0001; P9 |= 0x0001;
/* CAPCOM unit 2 used */ CC2_T78CON &= 0xFF00; /* Reset time 7 in timer CC2_T78CON |= 0x0000; CC2_T7REL = Period; /* Set timer T7 reload CC2_T7 = Period; /* reset T7 register */ CC2_M4 &= 0xFFF0; /* Reset CAPCOM2 CC2_M4 |= 0x0005; /* Initialise Compare mode 1*/ CC2_CC16= cv1;
CC2_CC16IC= 0x0044; /* enable CC16 interrupt, ILVL =1, GLVL =0 */
CC2_T78CON_T7R = 1; /* start T7 */
PSW_IEN = 1; /* allow all interrupts */
while(1); { } }