65 lines
2.0 KiB
C++
65 lines
2.0 KiB
C++
/*
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Smoothing
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Reads repeatedly from an analog input, calculating a running average
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and printing it to the computer. Keeps ten readings in an array and
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continually averages them.
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The circuit:
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* Analog sensor (potentiometer will do) attached to pin 15
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Created 22 April 2007
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By David A. Mellis <dam@mellis.org>
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http://www.arduino.cc/en/Tutorial/Smoothing
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Ported to Maple 27 May 2010
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by Bryan Newbold
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*/
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// Define the number of samples to keep track of. The higher the number,
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// the more the readings will be smoothed, but the slower the output will
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// respond to the input. Using a constant rather than a normal variable lets
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// use this value to determine the size of the readings array.
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const int numReadings = 10;
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int readings[numReadings]; // the readings from the analog input
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int index1 = 0; // the index1 of the current reading
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int total = 0; // the running total
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int average = 0; // the average
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int inputPin = 15; // analog input pin
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void setup() {
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// Declare the input pin as INPUT_ANALOG:
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pinMode(inputPin, INPUT_ANALOG);
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Serial.begin(115200); // Ignored by Maple. But needed by boards using hardware serial via a USB to Serial adaptor
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// Initialize all the readings to 0:
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for (int thisReading = 0; thisReading < numReadings; thisReading++) {
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readings[thisReading] = 0;
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}
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}
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void loop() {
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// Subtract the last reading:
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total = total - readings[index1];
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// Read from the sensor:
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readings[index1] = analogRead(inputPin);
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// Add the reading to the total:
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total = total + readings[index1];
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// Advance to the next position in the array:
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index1 = index1 + 1;
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// If we're at the end of the array...
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if (index1 >= numReadings) {
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// ...wrap around to the beginning:
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index1 = 0;
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}
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// Calculate the average:
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average = total / numReadings;
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// Send it to the computer (as ASCII digits)
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Serial.println(average, DEC);
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}
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