PIC18F4520
製作PID控制系統需要以下零件：PIC18F4520微控制器
LCD顯示屏
電位器
PWM模組
電容
電阻
輸入感測器
輸出設備（例如電機或LED燈）
以下PIC18F4520 PID控制系統的程式碼，您可以根據您的需求進行修改和優化：
#include <xc.h>
#include <stdlib.h>
#include <stdio.h>
#include "lcd.h"
#pragma config OSC = INTIO67
#pragma config FCMEN = OFF
#pragma config IESO = OFF
#pragma config PWRT = OFF
#pragma config BOREN = SBORDIS
#pragma config WDT = OFF
#pragma config MCLRE = ON
#pragma config PBADEN = OFF
#pragma config LVP = OFF
#define _XTAL_FREQ 8000000
int setpoint, input, output, error, last_error, integral, derivative;
int Kp = 1, Ki = 1, Kd = 1;
void interrupt isr(void) {
if (PIR1bits.TMR2IF) {
PIR1bits.TMR2IF = 0;
TMR2 = 0;
CCPR1L = output >> 2;
CCP1CONbits.DC1B1 = (output & 0b10) >> 1;
CCP1CONbits.DC1B0 = output & 0b01;
}
}
void init_pwm() {
TRISCbits.TRISC2 = 0;
PR2 = 199;
T2CON = 0b00000101;
CCP1CON = 0b00001100;
}
void init_adc() {
TRISA = 0b00001111;
ADCON1 = 0b00001110;
ADCON0 = 0b00000001;
}
int read_adc(int channel) {
ADCON0bits.CHS = channel;
__delay_us(20);
GO_nDONE = 1;
while (GO_nDONE);
return ADRESH << 8 | ADRESL;
}
void init_pid() {
last_error = 0;
integral = 0;
}
void calculate_pid() {
error = setpoint - input;
integral += error;
derivative = error - last_error;
last_error = error;
output = Kp * error + Ki * integral + Kd * derivative;
}
void main() {
OSCCONbits.IRCF = 0b111;
LCDInit();
init_adc();
init_pwm();
init_pid();
TMR2IE = 1;
PEIE = 1;
GIE = 1;
while (1) {
setpoint = 500; // set the desired setpoint
input = read_adc(0); // read the input from the sensor
calculate_pid(); // calculate the PID output
__delay_ms(20);
}
}
頁:
[1]