cannot measure frequency with FreqMeasure.h library arduino 101 Curie

Projects Programming
6

Thanks for your help,

I found this code.

will try with this one

volatile byte count = 0;
byte numCount = 8; //number of pulse intervals to measure

volatile unsigned long startTime;
volatile unsigned long endTime;
unsigned long copy_startTime;
unsigned long copy_endTime;

volatile boolean finishCount = false;
float period;

unsigned int rpm = 0;

void setup()
{
Serial.begin(115200);
Serial.println("start...");
//pinMode(2, INPUT_PULLUP);
attachInterrupt(digitalPinToInterrupt(2), isrCount, RISING);//interrupt on pin2
}

void loop()
{
if (finishCount == true)
{
finishCount = false;//reset flag
// disable interrupts, make protected copy of time values
noInterrupts();
copy_startTime = startTime;
copy_endTime = endTime;
count = 0;
interrupts();

period = (copy_endTime - copy_startTime) / 1000.0; //micros to millis
//debug prints
Serial.print(period); //total time for numCount
Serial.print('\t');
Serial.println(period/numCount);//time between individual pulses

//rpm = numCount * 60.0 * (1000.0 / period);//one count per revolution
rpm = numCount * 30.0 * (1000.0 / period);//two counts per revolution

Serial.print("RPM = ");
Serial.println(rpm);
}
}

void isrCount()
{
if (count == 0)//first entry to isr
{
startTime = micros();
}

if (count == numCount)
{
endTime = micros();
finishCount = true;
}
count++; //increment after test for numCount
}