Arduino NG User Manual

MotionSensor/Buffering/Buffering.ino
const unsigned int X_AXIS_PIN = 2;
Line 1
const unsigned int Y_AXIS_PIN = 1;
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const unsigned int Z_AXIS_PIN = 0;
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const unsigned int NUM_AXES = 3;
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const unsigned int PINS[NUM_AXES] = {
5
X_AXIS_PIN, Y_AXIS_PIN, Z_AXIS_PIN
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};
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const unsigned int BUFFER_SIZE = 16;
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const unsigned int BAUD_RATE = 9600;
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int buffer[NUM_AXES][BUFFER_SIZE];
10
int buffer_pos[NUM_AXES] = { 0 };
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void setup() {
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Serial.begin(BAUD_RATE);
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}
15
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int get_axis(const int axis) {
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delay(1);
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buffer[axis][buffer_pos[axis]] = analogRead(PINS[axis]);
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buffer_pos[axis] = (buffer_pos[axis] + 1) % BUFFER_SIZE;
20
long sum = 0;
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for (unsigned int i = 0; i < BUFFER_SIZE; i++)
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sum += buffer[axis][i];
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return round(sum / BUFFER_SIZE);
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}
25
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int get_x() { return get_axis(0); }
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int get_y() { return get_axis(1); }
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int get_z() { return get_axis(2); }
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void loop() {
30
Serial.print(get_x());
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Serial.print(" ");
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Serial.print(get_y());
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Serial.print(" ");
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Serial.println(get_z());
35
}
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As usual, we define some constants for the pins we use first. This time, we
also define a constant named NUM_AXES that contains the number of axes we
are measuring. We also have an array named PINS that contains a list of the
pins we use. This will help us keep our code more generic later.
In line 10, we declare buffers for all axes. They will be filled with the sensor
data we measure, so we can calculate average values when we need them.
We have to store our current position in each buffer, so in line 11, we define
an array of buffer positions.
setup only initializes the serial port; the real action takes place in get_axis .
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Arduino NG Specifications

General

Brand	Arduino
Model	NG
Category	Motherboard
Language	English