41 lines
1.0 KiB
C++
41 lines
1.0 KiB
C++
const int sampleWindow = 50; // Sample window width in mS (50 mS = 20Hz)
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int const AMP_PIN = 7; // Preamp output pin connected to A0
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unsigned int sample;
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void setup()
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{
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Serial.begin(9600);
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}
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void loop()
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{
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unsigned long startMillis = millis(); // Start of sample window
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unsigned int peakToPeak = 0; // peak-to-peak level
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unsigned int signalMax = 0;
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unsigned int signalMin = 1024;
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// collect data for 50 mS and then plot data
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while (millis() - startMillis < sampleWindow)
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{
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sample = analogRead(AMP_PIN);
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if (sample < 1024) // toss out spurious readings
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{
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if (sample > signalMax)
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{
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signalMax = sample; // save just the max levels
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}
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else if (sample < signalMin)
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{
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signalMin = sample; // save just the min levels
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}
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}
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}
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peakToPeak = signalMax - signalMin; // max - min = peak-peak amplitude
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if (peakToPeak == 4294966272){
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peakToPeak = 0;
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}
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Serial.println(peakToPeak);
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//double volts = (peakToPeak * 5.0) / 1024; // convert to volts
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//Serial.println(volts);
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} |