I am new with sensors such as accelerometers, therefore, I decided to check the code in the examples section. I always want to understand the code before I use it, so I read it and did not understand this part...
/*
Memsic2125
Read the Memsic 2125 two-axis accelerometer. Converts the
pulses output by the 2125 into milli-g's (1/1000 of earth's
gravity) and prints them over the serial connection to the
computer.
The circuit:
- X output of accelerometer to digital pin 2
- Y output of accelerometer to digital pin 3
- +V of accelerometer to +5V
- GND of accelerometer to ground
created 6 Nov 2008
by David A. Mellis
modified 30 Aug 2011
by Tom Igoe
This example code is in the public domain.
*/
// these constants won't change:
const int xPin = 2; // X output of the accelerometer
const int yPin = 3; // Y output of the accelerometer
void setup() {
// initialize serial communications:
Serial.begin(9600);
// initialize the pins connected to the accelerometer
// as inputs:
pinMode(xPin, INPUT);
pinMode(yPin, INPUT);
}
void loop() {
// variables to read the pulse widths:
int pulseX, pulseY;
// variables to contain the resulting accelerations
int accelerationX, accelerationY;
// read pulse from x- and y-axes:
pulseX = pulseIn(xPin,HIGH);
pulseY = pulseIn(yPin,HIGH);
// convert the pulse width into acceleration
// accelerationX and accelerationY are in milli-g's:
// earth's gravity is 1000 milli-g's, or 1g.
accelerationX = ((pulseX / 10) - 500) * 8;
accelerationY = ((pulseY / 10) - 500) * 8;
// print the acceleration
Serial.print(accelerationX);
// print a tab character:
Serial.print("\t");
Serial.print(accelerationY);
Serial.println();
delay(100);
}
I what unit is PulseX and Y measured in order to do the formula?
What is the logic of PulseX and Y, AccelerationX and Y?
Thank you in advance
Alrro