Using a mouse for X-Y tracking:
Some links:
http://www.martijnthe.nl/2009/07/interfacing-an-optical-mouse-sensor-to-your-arduino/
http://arduino.cc/playground/Main/InterfacingWithHardware#mouse
http://www.computer-engineering.org/ps2mouse/ (detailed specs for PS/2 protocol)
/*******************************/
ADS2051 */
the A2051 uses a simple SPI connection. For more information on registers
The program is fairly simple, it sends the two types of information:
1 to 1 frame> ID-ID-Move X-Y displacement at each mouse movement;
2 - the image seen by the sensor (camera 16x16 pixels) for each character you enverez on the serial link.
image data is hexadecimal, two characters per gray value of a pixel, 256 pixels.
The displacements are given in 2's complement, relative since the last reading.
/*******************************/
#define CLK_PIN 2
#define DATA_PIN 3
#define _BV(bit) (1 << (bit))
byte readRegister (byte address)
{
byte retval = 0;
pinMode (DATA_PIN, OUTPUT);
for (int i = 7; i >= 0; i--) {
digitalWrite (CLK_PIN, LOW);
digitalWrite (DATA_PIN, address & (1 << i));
digitalWrite (CLK_PIN, HIGH);
}
pinMode (DATA_PIN, INPUT);
delayMicroseconds(100);
for (int i = 7; i >= 0; i--) {
digitalWrite (CLK_PIN, LOW);
digitalWrite (CLK_PIN, HIGH);
retval |= (digitalRead (DATA_PIN) << i);
}
delayMicroseconds(100);
return retval;
}
void writeToRegister (byte address, byte data)
{
address |= 0x80;
pinMode (DATA_PIN, OUTPUT);
for (int i = 7; i >= 0; i--) {
digitalWrite (CLK_PIN, LOW);
digitalWrite (DATA_PIN, address & (1 << i));
digitalWrite (CLK_PIN, HIGH);
}
for (int i = 7; i >= 0; i--) {
digitalWrite (CLK_PIN, LOW);
digitalWrite (DATA_PIN, data & (1 << i));
digitalWrite (CLK_PIN, HIGH);
}
}
void sendImage()
{
byte val;
byte adr;
Serial.print (">IMG:");
writeToRegister (0x0a, 0x09);
for (int i = 0; i < 256; i++) {
do {
adr = readRegister (0x0d);
val = readRegister (0x0c);
} while (val & 0x80);
// Serial.print (adr, HEX);
// Serial.print ('>', BYTE);
Serial.print (val, HEX);
// Serial.print (13, BYTE);
}
Serial.println ();
writeToRegister (0x0a, 0x00);
}
void setup()
{
pinMode (CLK_PIN, OUTPUT);
pinMode (DATA_PIN, INPUT);
Serial.begin(19200);
}
void loop ()
{
if (readRegister (0x02)) {
Serial.print ('>');
Serial.print (readRegister (0x00), DEC);
Serial.print ('-');
Serial.print (readRegister (0x01), DEC);
Serial.print ('-');
Serial.print (readRegister (0x03), DEC);
Serial.print ('-');
Serial.print (readRegister (0x04), DEC);
Serial.println ();
}
if (Serial.available()) {
Serial.read();
sendImage();
}
}
We only need to connect 4 pins of the sensor to the Arduino, (two for data and two for the power supply).
The sensor uses bi-directional serial communcation over one data line (SDIO, pin 3).
The second data pin (SCLK, pin 4) is used to time the bits.
Connect the SCLK to Arduino digital pin 2 and SDIO to Arduino digital pin 3.
On most Arduino boards, SDA (data line) is on analog input pin 4, and SCL (clock line) is on analog input pin 5
There are both 7- and 8-bit versions of I2C addresses.
7 bits identify the device, and the eighth bit determines if it's being written to or read from.
The Wire library uses 7 bit addresses throughout. If you have a datasheet or sample code that uses 8 bit address,
you'll want to drop the low bit (i.e. shift the value one bit to the right), yielding an address between 0 and 127.
