[bluepine]

#include <16f877a.h>
#fuses HS,NOPROTECT,NOWDT,NOBROWNOUT
#use delay (clock = 20000000)
// Giao tiep vi dieu khien
#use rs232(baud=9600, xmit=PIN_C6, rcv=PIN_C7, parity=N, bits=8) // Giao tiep RS232

#include <stdlib.h>
#include <string.h>
#include <math.h>
#include<ctype.h>


#byte PR2 = 0x92

int16 e2;
int16 e1;
///////////////////////////////////////////////////////

int16 v_set = 350;

/////////////////////////////////////////////////////////
int16 v_cur;
int16 e_sum;
int16 e_del;
int16 flag_timer0;


//////////////////// cac thong so pid ban co the thay doi cho 
//////////////////// phu hop voi dong co cua ban
unsigned long kp =2.5;
unsigned long ki = 0.0092;
unsigned long kd = 0;
////////////////////////////////////////////////////////////

int16 i = 1 ;
int16 pw_duty;
int16 counted_round_value;
int16 temp_timer0;
int16 temp_timer1;
int16 update_counted_round_value;

//#byte TMR0 = 0x01 //timer0 REGISTER
//#byte TMR1_L = 0X0E
//#byte TMR1_H = 0X0F

#define START_VALUE_TIMER0 5 //tri khoi tao ban dau cua timer0 5, so xung dem duoc moi khi ngat la 255 - 5
#define START_VALUE_TIMER1 5535 //tri khoi tao ban dau cua timer1 65536-5536=60000


#INT_TIMER0 // ngat timer0 tang bien len 1
void TIMER0_int()
{

set_timer0(START_VALUE_TIMER0);
i++;

///////////// ban sai cho nay

if(i==60 ){

temp_timer1 = get_timer1();
set_timer1(START_VALUE_TIMER1);
i=0;

v_cur =  2*(temp_timer1 - START_VALUE_TIMER1);

flag_timer0 = 1;
}

}

#INT_TIMER1  /// thuc hien khi ngat timer 1
void timer1_int(){
set_timer1(START_VALUE_TIMER1);


}

void init_timer0()
{

setup_timer_0(RTCC_INTERNAL | RTCC_DIV_16); // moi lan tran timer0 tuong ung 250*16*1/5 us = 0.8ms,chu ky lay mau=0.8*60=48ms


setup_timer_1(T1_EXTERNAL | T1_DIV_BY_2); //  he so chia la 2 moi lan tran timer0 , khoi tao lai luon gia tri dem xung timer1

enable_interrupts(GLOBAL);
enable_interrupts(INT_TIMER0);
enable_interrupts(INT_TIMER1);

}

void init_PWM(int16 frequency){

setup_ccp1(CCP_PWM); // initiate PWM
PR2 = 20000000/4/frequency - 1; // set PWM period

setup_timer_2(T2_DIV_BY_1,255,1); // initiate time 2 The cycle time will be (1/clock)*4*t2div*(period+1)
// (1/20000000)*4*1*(255+1) = 51.2 us( will over flow every 51.2 us, will intrup every 51.2 uS or 19.5 khz;

}

void cal_pid(){

long temp_kp;
long temp_ki;
long temp_kd;
e2 = v_set - v_cur;
e_sum += e2;
e_del = e2 - e1;
e1 = e2;

temp_kp = kp*e2;
temp_ki = ki*e_sum;
temp_kd = kd*e_del;
pw_duty +=temp_kp;

if (pw_duty <1000)
pw_duty += temp_ki;
if (pw_duty <1000)
pw_duty += temp_kd;
if (pw_duty <256) // vi khi pw_duty <256 thi PWM chi dieu rong xung 8 bit / //chu khong phai 10 bit,
pw_duty = 256;
if (pw_duty >1000) // bao hoa
pw_duty = 1000;

printf(" \t%ld", v_cur); // truyen toc do xung ve may tinh hien thi tren Hyperterminal
}

void main()
{
int8 timer0_value;

init_timer0();
init_PWM(19500);
//set_pwm1_duty(500);
while(true){
if (flag_timer0 ==1){
flag_timer0 = 0;
cal_pid();
set_pwm1_duty(pw_duty);
}
}
}

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thân,