UINT_MAX was not declared

Projects Programming
1

Hi all,

I'm just trying to work with this sketch to control wind speed from an anemometer. Everything works, but when I want to knot the gust (or the highest wind speed of the measuring period) I received an error:'UINT_MAX' was not declared in this scope. The error comes from the last line of the code

Anybody could help me to understand and fix the problem?

Thank's

Eduard

#include <math.h>
//Variable to setup the machine ON
unsigned long vtime; //Declara un variable del mismo tipo que la que devuelve micros()


// Each time we loop through the main loop, we check to see if it's time to capture the sensor readings
unsigned int sensorCapturePeriod = 100;
unsigned int vtimeNextSensorReading;

void setup() {

  initializeAnemometer();

  // Schedule the next sensor reading and publish events
  vtimeNextSensorReading = millis() + sensorCapturePeriod;
}

void loop() {

  vtime = millis();
  // Capture any sensors that need to be polled
  // The wind speed sensors use interrupts, and so data is collected "in the background"

  if (vtimeNextSensorReading <= millis()) {


    // Schedule the next sensor reading
    vtimeNextSensorReading = millis() + sensorCapturePeriod;
  }

  // Publish the data collected

  float gustKPH;
  float windKPH = (getAndResetAnemometerkph(&gustKPH));
  float knots = windKPH * 0.5399;

  delay(1000);

  //print data
  String SPKwind = String(windKPH);
  String SPKgust = String(gustKPH);
  String SPKknots = String(knots);
  Serial.print("WindKPH");
  Serial.println(SPKwind);

  delay(10);




}


//===========================================================================
// Wind Speed (Anemometer)
//===========================================================================

int AnemometerPin = 5;
float AnemometerScalekph = 1.492; // Windspeed if we got a pulse every second (i.e. 1Hz)
volatile unsigned int AnemoneterPeriodTotal = 0;
volatile unsigned int AnemoneterPeriodReadingCount = 0;
volatile unsigned int GustPeriod = UINT_MAX;
unsigned int lastAnemoneterEvent = 0;

void initializeAnemometer() {
  pinMode(AnemometerPin, INPUT_PULLUP);
  AnemoneterPeriodTotal = 0;
  AnemoneterPeriodReadingCount = 0;
  GustPeriod = UINT_MAX;  //  The shortest period (and therefore fastest gust) observed
  lastAnemoneterEvent = 0;
  attachInterrupt(AnemometerPin, handleAnemometerEvent, FALLING);
  return;
}

void handleAnemometerEvent() {
  // Activated by the magnet in the anemometer (2 ticks per rotation), attached to input D3
  unsigned int vtimeAnemometerEvent = millis(); // grab current time

  //If there's never been an event before (first time through), then just capture it
  if (lastAnemoneterEvent != 0) {
    // Calculate time since last event
    unsigned int period = vtimeAnemometerEvent - lastAnemoneterEvent;
    // ignore switch-bounce glitches less than 10mS after initial edge (which implies a max windspeed of 149kph)
    if (period < 10) {
      return;
    }
    //       if(period < GustPeriod) {
    //            // If the period is the shortest (and therefore fastest windspeed) seen, capture it
    //            GustPeriod = period;
    //        }
    AnemoneterPeriodTotal += period;
    AnemoneterPeriodReadingCount++;
  }

  lastAnemoneterEvent = vtimeAnemometerEvent; // set up for next event
}

float getAndResetAnemometerkph(float * gustKPH)
{
  if (AnemoneterPeriodReadingCount == 0)
  {
    *gustKPH = 0.0;
    return 0;
  }
  float result = AnemometerScalekph * 1000.0 * float(AnemoneterPeriodReadingCount) / float(AnemoneterPeriodTotal);
  AnemoneterPeriodTotal = 0;
  AnemoneterPeriodReadingCount = 0;
  *gustKPH = AnemometerScalekph  * 1000.0 / float(GustPeriod);
  GustPeriod = UINT_MAX;
  return result;
}
2

Well, you need to define UINT_MAX before you can use it. Try to add

#include <math.h>

#define UINT_MAX 65535
3

Hi

soooo stupid from me!!

thank's

4

First something different:

 // Schedule the next sensor reading and publish events
  vtimeNextSensorReading = millis() + sensorCapturePeriod;

This will go wrong when millis() rolls over. ALWAYS check time in the way:

millis() - lastMillis >= interval

That way the roll over has no consequence.

[edit]To slowwwwwwwwww :p[/edit]
But to the problem, for which device do you try to compile? And where do you think INT_MAX should be defined?

5

I think you need to include limits.h or climits.

6

arduino_new:
Well, you need to define UINT_MAX before you can use it. Try to add

#define UINT_MAX 65535

Or
#define UINT_MAX ((unsigned int)~0)

But yeah - better to include limits.h (if that's the correct one).