Controller Calibration of sensors

[Ben Andrewes]

@gohan said in Controller Calibration of sensors:

sht31

Unfortunately as I'm intending to make over 10 of the same sensor cost becomes a consideration - I think the sht31 are about £4 more than the DHTs... My wife only allows me so much pocket money :)

(I also bought a load of DHT11s before I really had any idea of what I was doing so need to use them up)

[Ben Andrewes]

@mfalkvidd that worked for me (I had tried it but was saving the data to a different part of the eeprom than I thought).

Cheers

[mfalkvidd]

Great work!

Today I noticed that Domoticz seems to have some sort of built-in offset support:

I haven't tried it though, and your solution is more versatile since it works regardless of controller.

[gohan]

@Ben-Andrewes consider a Dallas temperature sensor as it is cheap and more reliable than a dht11. There are also dht22 that is still cheap but better than dht11

[Ben Andrewes]

@mfalkvidd Damn - I hadn't noticed that - would've saved some time! Oh well, I learnt a bit about programming whilst I was doing it... :)

@gohan I have a dallas sensor so might try that, and they are cheap. I think I got a bit carried away with he idea that the DHT would do humidity as well - not that I really know why I want to know the humidity...!

If it is of any interest, I'm thinking of adding gesture recognition and reporting to the sensor using an APDS-9960 - I've seen a sketch that uses the APDS-9960, is this a good bit of kit or should I try to use something else?

I sort of have an idea of a sensor which has a couple of relays on that I can control from Domoticz, and also reports temp/hum, presence via PIR, and gesture controls to Domoticz which will then handle the logic.....

[mfalkvidd]

@Ben-Andrewes the apds-9960 is fun. I did a project a while back (check the videos), but I only used the distance meter, not the gesture recognition.

[Ben Andrewes]

@mfalkvidd That looks very cool, great work.

Unfortunately, I'm having trouble with the code for the apds9960 and I think that the interrupt isn't working properly - it seems to fire once then the interrupt is stuck low. I've now tried a test sketch from Sparkfun (official example sketch) without any mysensors stuff and added some serial prints to read the state of the interrupt pin every 5 secs and it always returns 0. Any idea why this might be? Do I need to send a message to the sensor to reset the interrupt back to high after it runs the interruptRoutine?

#include <Wire.h>
#include <SparkFun_APDS9960.h>

// Pins
#define APDS9960_INT    3  // Needs to be an interrupt pin

// Constants

// Global Variables
SparkFun_APDS9960 apds = SparkFun_APDS9960();
volatile int isr_flag = 0;

unsigned long SLEEP_TIME = 5000; // Sleep time between reads (in milliseconds)
unsigned long lastRefreshTime = 0; // Use this to implement a non-blocking delay function
void interruptRoutine();
void handleGesture();

void setup() {

  // Set interrupt pin as input
  pinMode(APDS9960_INT, INPUT);
    Serial.println("Pin state is:");
    Serial.println(digitalRead(APDS9960_INT));
  // Initialize Serial port
  Serial.begin(9600);
  Serial.println();
  Serial.println(F("--------------------------------"));
  Serial.println(F("SparkFun APDS-9960 - GestureTest"));
  Serial.println(F("--------------------------------"));

  //define sensitivty
  apds.setGestureGain( 0 );

    // Initialize interrupt service routine
  
  attachInterrupt(digitalPinToInterrupt(APDS9960_INT), interruptRoutine, FALLING);


  // Initialize APDS-9960 (configure I2C and initial values)
  if ( apds.init() ) {
    Serial.println(F("APDS-9960 initialization complete"));
  } else {
    Serial.println(F("Something went wrong during APDS-9960 init!"));
  }
  
  // Start running the APDS-9960 gesture sensor engine
  if ( apds.enableGestureSensor(true) ) {
    Serial.println(F("Gesture sensor is now running"));
  } else {
    Serial.println(F("Something went wrong during gesture sensor init!"));
  }

}

void loop() {

  boolean needRefresh = (millis() - lastRefreshTime) > SLEEP_TIME;
  if (needRefresh)
  {
    lastRefreshTime = millis();
    Serial.println("I'm Alive");
    Serial.println("Pin state is:");
    Serial.println(digitalRead(APDS9960_INT));

  }  
  if( isr_flag == 1 ) {
    Serial.println("Interrupt");
    detachInterrupt(digitalPinToInterrupt(APDS9960_INT));
    handleGesture();
    Serial.print("returned from handling gesture");
    isr_flag = 0;
    Serial.println(isr_flag);
    attachInterrupt(digitalPinToInterrupt(APDS9960_INT), interruptRoutine, FALLING);
    Serial.println("attachInterrupt executed");
  }
}

void interruptRoutine() {
  Serial.println("Interrupt Routine started");
  isr_flag = 1;
}

void handleGesture() {
  Serial.println("Handling gesture");
    //if ( apds.isGestureAvailable() ) {
      //Serial.println("apds.isGestureAvailable() has returned true");
/****************
    switch ( apds.readGesture() ) {
      case DIR_UP:
        Serial.println("UP");
        break;
      case DIR_DOWN:
        Serial.println("DOWN");
        break;
      case DIR_LEFT:
        Serial.println("LEFT");
        break;
      case DIR_RIGHT:
        Serial.println("RIGHT");
        break;
      case DIR_NEAR:
        Serial.println("NEAR");
        break;
      case DIR_FAR:
        Serial.println("FAR");
        break;
      default:
        Serial.println("NONE");
    }
    *******************/
  // }
  
}

[mfalkvidd]

@Ben-Andrewes maybe the interrups doesn't get cleared until you read the sensor?

A side note: Doing Serial prints from an interrupt routine can result in strange results. Remove it to make sure you're not chasing ghosts.

[mfalkvidd]

From the datasheet:

Gesture Interrupts flags: GINT, GVALID, and GFLVL are cleared by emptying e. all data has been read).

[Ben Andrewes]

Thanks @mfalkvidd - you're right, the interrupt would never be cleared until the code read the gesture. I uncommented the readGesture only to find that the code hanged at that point (think that was why I commented it out before - I'd had a beer or two).

I think I really need to spend a bit of time learning about the Arduino programming language, and libraries etc as my programming knowledge is based on BASIC 30yrs ago and a bit of VBA at work. At the moment my arduino programming is just hacking stuff together and seeing if it works...

Anyway I found that it was the library that IDE installed was wrong and I needed to get the library direct from Sparkfun... Now it works fine so I just need to MySensorise it...