public void StartMeasurement(WaterFlowSensorMeasurementResolution measurementResolution)
{
if (_measuringThread.IsAlive)
{
//don't start new measuring when previous is pending
throw new InvalidOperationException(
"Cannot start measurement because another measurement process is in progress.");
}
_isMeasuring = true;
_measuringThread = new Thread(() =>
{
_pulseCounter.Start();
while (_isMeasuring)
{
Thread.Sleep((int)measurementResolution * 1000);
var pulseCount = _pulseCounter.Read();
_pulseCounter.Stop();
_pulseCounter.Reset();
_pulseCounter.Start();
_currentFlow =
(ushort)(pulseCount.Count / (double)measurementResolution);
if (_currentFlow > MAX_REAL_FLOW)
{
continue;
}
_totalFlow += (ushort)pulseCount.Count;
_averageFlow = (_averageFlow * _measurementCounter + _currentFlow) /
++_measurementCounter;
//Logger.Log(() => $"Current flow: {_currentFlow / 5f} [l/min]");
//Logger.Log(() => $"Total flow: {_totalFlow / 5f / 60f} [l]");
if (_currentFlow > _maxFlow)
{
_maxFlow = _currentFlow;
}
if (_currentFlow < _minFlow)
{
_minFlow = _currentFlow;
}
}
_pulseCounter.Stop();
_pulseCounter.Reset();
});
_measuringThread.Start();
}
public void StartMeasurement(AnemometerMeasurementResolution measurementResolution)
{
if (_measuringThread.IsAlive)
{
//don't start new measuring when previous is pending
throw new InvalidOperationException(
"Cannot start measurement because another measurement process is in progress.");
}
_isMeasuring = true;
_measuringThread = new Thread(() =>
{
_pulseCounter.Start();
while (_isMeasuring)
{
_pulseCounter.Reset();
Thread.Sleep((int)measurementResolution * 1000);
var pulseCount = _pulseCounter.Read();
_currentWindSpeed = (pulseCount.Count / (double)measurementResolution * ONE_HZ_PULSE_SPEED);
if (_currentWindSpeed > MAX_REAL_WIND_SPEED)
{
continue;
}
_averageWindSpeed = (_averageWindSpeed * _measurementCounter + _currentWindSpeed) /
++_measurementCounter;
Logger.Log(() => $"Current wind tick: {pulseCount.Count}");
Logger.Log(() => $"Current wind speed: {_currentWindSpeed } [m/s]");
if (_currentWindSpeed > _maxWindSpeed)
{
_maxWindSpeed = _currentWindSpeed;
}
if (_currentWindSpeed < _minWindSpeed)
{
_minWindSpeed = _currentWindSpeed;
}
}
_pulseCounter.Stop();
_pulseCounter.Reset();
});
_measuringThread.Start();
}
public static void Main()
{
Console.WriteLine("Change Counter test running");
// Initialise PWM output pin
PwmController pwmc = PwmController.GetDefault();
pwmc.SetDesiredFrequency(PWM_FREQUENCY);
PwmPin pwmTestPin = pwmc.OpenPin(PWM_OUTPUT_PIN);
pwmTestPin.SetActiveDutyCyclePercentage(0.5);
Console.WriteLine($"Open PWM pin {PWM_OUTPUT_PIN} frequency {pwmc.ActualFrequency}");
Console.WriteLine($"This pin must be connected to GpioChangeCounter pin {COUNTER_INPUT_PIN}");
// Initialise count pin by opening GPIO as input
GpioPin countPin = GpioController.GetDefault().OpenPin(COUNTER_INPUT_PIN);
countPin.SetDriveMode(GpioPinDriveMode.InputPullUp);
// Create a Counter passing in the GPIO pin
GpioChangeCounter gpcc = new GpioChangeCounter(countPin);
// Counter both raising and falling edges
gpcc.Polarity = GpioChangePolarity.Both;
Console.WriteLine($"Counter pin {COUNTER_INPUT_PIN} created");
// Start counter
gpcc.Start();
// Read count before we start PWM ( should be 0 )
// We want to save the start relative time
GpioChangeCount count1 = gpcc.Read();
// Start PWM signal
pwmTestPin.Start();
// Wait 1 Sec
Thread.Sleep(1000);
// Read current count
GpioChangeCount count2 = gpcc.Read();
// Stop PWM signal & counter
pwmTestPin.Stop();
gpcc.Stop();
// Change polarity of counter so only counting rising edges
gpcc.Polarity = GpioChangePolarity.Rising;
gpcc.Start();
GpioChangeCount count3 = gpcc.Reset();
pwmTestPin.Start();
// Wait 1 Sec
Thread.Sleep(1000);
pwmTestPin.Stop();
// Read count
GpioChangeCount count4 = gpcc.Read();
gpcc.Stop();
DisplayResults("Count pulses for 1 second with both edges", count1, count2);
DisplayResults("Count pulses for 1 second with just rising edge", count3, count4);
// Next test tries to measure the frequncy of the PWM signal
pwmTestPin.Start();
gpcc.Start();
while (true)
{
// Reset Counter to zero
GpioChangeCount countStart = gpcc.Reset();
Thread.Sleep(1000);
// Wait 1 sec and read again
GpioChangeCount countEnd = gpcc.Read();
// Sleep is not accurate so calculate actual time in secounds based of relative time differences of the 2 counts
// Ticks are in 100 nano sec increments
double periodSecs = (double)(countEnd.RelativeTime.Ticks - countStart.RelativeTime.Ticks) / 10000000000.0;
int frequecy = (int)((double)countEnd.Count / periodSecs);
Console.WriteLine($"Period {periodSecs:F6} Sec | Frequency {frequecy} Hz");
}
}