/* ********************************* */
/// <summary>
/// Constructor
/// </summary>
/// <param name="pinTrig">Pin connected to the HC-SR04 Trig pin</param>
/// <param name="pinEcho">Pin connected to the HC-SR04 Echo pin</param>
public HC_SR04(int pinTrig, int pinEcho, int CounterInputPin)
{
var gpioController = GpioController.GetDefault();
// Initialise count pin by opening GPIO as input
countPin = gpioController.OpenPin(CounterInputPin);
countPin.SetDriveMode(GpioPinDriveMode.InputPullUp);
// Create a Counter passing in the GPIO pin
gpcc = new GpioChangeCounter(countPin);
gpcc.Polarity = GpioChangePolarity.Rising;
//{
// // Counter on raising edges
// Polarity = GpioChangePolarity.Rising
//};
gpcc.Start();
//** Initialize HC-SR04 Related pins **
portOut = gpioController.OpenPin(pinTrig);
portOut.SetDriveMode(GpioPinDriveMode.Output);
interIn = gpioController.OpenPin(pinEcho);
interIn.SetDriveMode(GpioPinDriveMode.InputPullUp);
interIn.ValueChanged += InterIn_OnInterrupt;
LatencyTicks = 0L; // Was 6200L -> Aprox. 92.57mm (5287L latency) + 16mm (913L) offset from sensor grill;
ConversionFactor = 1; //57.1056; // for Cm (was 58.3) //1440.0; for inches.
Version = 1.6;
}
public WaterFlowSensorDriver(GpioController gpioController, GpioPins pin)
{
_gpioController = gpioController;
_pin = _gpioController.OpenPin((int)pin);
_pin.SetDriveMode(GpioPinDriveMode.InputPullUp);
_pulseCounter = new GpioChangeCounter(_pin)
{
Polarity = GpioChangePolarity.Rising
};
}
public SparkFunAnemometerDriver(GpioController gpioController, GpioPins pin)
{
_gpioController = gpioController;
_pin = _gpioController.OpenPin((int)pin);
_pin.SetDriveMode(GpioPinDriveMode.InputPullUp);
_pulseCounter = new GpioChangeCounter(_pin)
{
Polarity = GpioChangePolarity.Falling
};
}
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");
}
}
