I am unable to change the fan speed. (getting the max value and fan goes at full speed but unable to get min value). I have attached the code below. Any help or feedback will be highly appreciated. Thanks!
Arduino_IN_One.ino (4.16 KB)
Posting your code inline with code tags is more likely to get you help and more likely to get help sooner...
#include <PID_v1.h>
// Sample Arduino MAX6675 Arduino Sketch
// MAX6675 library - Version: Latest
#include <max6675.h>
#include <SoftwareSerial.h>
int val, val2;
int ktcSO = 11 ;
int ktcCS = 12;
int ktcCLK = 13;
int compVal = 160;
int yy;
int delayTime = 330;
// TRIAC delay-to-fire time intialized to Max Speed
MAX6675 ktc(ktcCLK, ktcCS, ktcSO);
//Define Variables we'll be connecting to
double Setpoint, Input, Output, TempSense; //Changed Output from double to integer which is sent to zero cross delay action
//Specify the links and initial tuning parameters
PID myPID(&Input, &Output, &Setpoint,12,4,2,P_ON_M, REVERSE); //P_ON_M specifies that Proportional on Measurement be used
//P_ON_E (Proportional on Error) is the default behavior
#include <avr/io.h>
#include <avr/interrupt.h>
#include <SoftwareSerial.h>
byte i;
byte low, high;
#define DETECT 2 //zero cross detect
#define GATE 9 //TRIAC gate
#define PULSE 4 //trigger pulse width (counts)
//int y = 340;
int y_old = 340;
word y;
void setup()
{
//Serial Communications
Serial.begin(9600);
// give the MAX a little time to settle
delay(500);
//Next lines use for exporting to Excel (Using PLX-DAQ) - MUST REMOVE UNWANTED SERIAL PRINT
//Serial.println("CLEARDATA"); //clears up any data left from previous projects
//Serial.println("LABEL,TIME,TEMPERATURE");
//always write LABEL, so excel knows the next things will be the names of the columns (instead of Acolumn you could write Time for instance)
//Serial.println("RESETTIMER"); //resets timer to 0
//initialize the variables we're linked to
//optical encoder code goes here
Input = analogRead(0);
Setpoint = 050;// SETPOINT FOR DESIRED TEMPERATURE
//turn the PID on
myPID.SetMode(AUTOMATIC);
myPID.SetOutputLimits(160, 340); //Output from PID is set between 160(Fast) and 340(Slow)
// set up pins
pinMode(DETECT, INPUT); //zero cross detect
digitalWrite(DETECT, HIGH); //enable pull-up resistor
pinMode(GATE, OUTPUT); //TRIAC gate control
// set up Timer1
//(see ATMEGA 328 data sheet pg 134 for more details)
OCR1A = 160; //initialize the comparator - Set to Minimum Fan Speed 160(High) - 340(Low)
TIMSK1 = 0x03; //enable comparator A and overflow interrupts
TCCR1A = 0x00; //timer control registers set for
TCCR1B = 0x00; //normal operation, timer disabled
// set up zero crossing interrupt
attachInterrupt(0,zeroCrossingInterrupt, RISING);
//IRQ0 is pin 2. Call zeroCrossingInterrupt
//on rising signal
delay(500);
}
//Interrupt Service Routines
void zeroCrossingInterrupt(){ //zero cross detect
TCCR1B=0x04; //start timer with divide by 256 input
TCNT1 = 0; //reset timer - count from zero
}
ISR(TIMER1_COMPA_vect){ //comparator match
digitalWrite(GATE,HIGH); //set TRIAC gate to high
TCNT1 = 65536-PULSE; //trigger pulse width
}
ISR(TIMER1_OVF_vect){ //timer1 overflow
digitalWrite(GATE,LOW); //turn off TRIAC gate
TCCR1B = 0x00; //disable timer stopd unintended triggers
}
void loop()
{
delay(500);//Needed for MAXX6675 chip
TempSense = ktc.readFahrenheit();
//Serial.print("DATA,TIME,"); //writes the time in the first column A and the time since the measurements started in column B
// Serial.print("\nDeg F = ");
//Serial.print(TempSense);
//Serial.println();
Input = TempSense;
myPID.Compute();
delayTime = (int)Output;
//Serial.print(delayTime);
//Serial.println();
val = delayTime;
i = (byte)val;
byte h = highByte(i);
byte l = lowByte(i);
y = word(h, l);
yy = (int)y;
if(yy < compVal)//If no useful value received over serial use previous value
{
yy = y_old;
}
if(yy > 340)
{
yy = y_old;
}
OCR1A = y;//set the compare register brightness desired.
y_old = y;
Serial.print("TRIAC = ");
Serial.print(OCR1A);
Serial.println();
}
Setpoint = 050;// SETPOINT FOR DESIRED TEMPERATURE
Octal. That's a brave choice.
Not the adjective I would have used.
I am unable to change the fan speed.
Please explain how you are attempting to change the fan speed, what should happen and what happens instead.
PaulS:
Not the adjective I would have used.
And I appreciate your discretion in not using that adjective.
Having the delay() within loop seems counter intuitive...
(Octal made perfect sense back in the days of PDP-11s)