Notes

Experiment 5

part 1:
Period/ Frequency Meter
using Timer1 and Module
CCP1 in Cap-ture Mode
---
ISIS:
pin 25 : to virtual terminal

RC0:connected with signal generator (sin)
then connected to osclliscope (pin A)

the other pin in signal generator (squ)
connected to gnd.
-----
code :
void main(void)
{
unsigned int t1, t2, Nticks;
float Tmc, period, freq;
OSCCON=0x60;
ADCON1=0xF;
serial_init(25,1);
CCP1CON=0x05;
TRISC2=1;
T3CON=0x40;
CCP1IF=0;
TMR3L=TMR3H=0;
while(CCP1IF==0);
TMR3ON=1;
t1=(CCPR1H<<8)+CCPR1L;
CCP1IF=0;
while(CCP1IF==0);
TMR3ON=0;
CCP1CON=0x0;
t2=(CCPR1H<<8)+CCPR1L;
Nticks=t2-t1;
Tmc=(4.0/4);
period=Tmc*Nticks;
freq=1e6/period;
printf("t1=%d,t2=%d, Nticks=%d, Tmc=%g us, period=%g us, freq=%g Hzrn",
t1, t2, Nticks, Tmc, period, freq);
while(1);
}
#############
part 2:
Square Wave Generation using
Timer3 and Module CCP2 in
Com-pare Mode
-------
ISIS: same in part1
--------
code:
#include "ee470.h"
void main(void)
{
OSCCON=0x70;// 8 MHz internal OSC
ADCON1=0xF; // all digital
CCP1CON=0x02; // toggle RC2 on compare match
T3CON=0x0; // use Timer1 with capture/compare
T1CON=0x0; // pre=1
TRISC2=0;
CCPR1H=40000>>8; // =0x9c
CCPR1L=(400000<<8)>>8; // = 0x40
TMR1ON=1;
while(1)
{
CCP1IF=0;
TMR1H=TMR1L=0;
while(CCP1IF==0);
}
}
############
part3:Square Wave Generation
using Module CCP1 in PWM Mode

*Generate a square wave having a
frequency of 1.5KHz and a duty
cycle of 75% using module CCP1
running in PWM mode. Take fosc=1MHz
-----
ISIS:
RA0: 10K to VCC then switch to gnd
pin17 :to osclliscope (pin A)
RB0:10k to led to gnd
----
code :
#include "ee470.h"
void main(void)
{
OSCCON=0x70;
ADCON1=0xF;
T2CON=0x01;
PR2=199;
CCPR1L=(unsigned char) 199*0.75;
TRISC2=0;
TRISA0=1;
TRISB0=0;
CCP1CON=0x1C;
TMR2=0;
TMR2ON=1;
while(1)
{
RB0=RA0;
}
}