Arduino

/*******************************************************
 * name:Joystick PS2
 * function:push the joystick and the coordinates of X and Y axes displayed on Serial Monitor will change accordingly;
 * press down the joystick, and the coordingly of Z=0 will also be displayed.
 * connection:
 * Joystick PS2    Arduino Uno R3
 * GND    GND
 * VCC    5V
 * SW     7
 * x      A0
 * Y      A1
 * ******************************************************/
 const int xPin = A0;   //X attach to A0
 const int yPin = A1;   //Y attach to A1
 const int btPin = 7;   //Bt attach to digital 7

 void setup()
 {
  pinMode(btPin, INPUT);
  digitalWrite(btPin, HIGH);
  Serial.begin(9600);
 }

 void loop()
 {
  Serial.print("X: ");
  Serial.print(analogRead(xPin), DEC); //read the value of A0 and print it in decimal
  Serial.print("\tY: ");
  Serial.print(analogRead(yPin), DEC);
  Serial.print("\tZ: ");
  Serial.println(digitalRead(btPin));
  delay(100);//100ms
 }

树莓派

C

#include <stdio.h>
#include <wiringPi.h>
#include <pcf8591.h>

#define PCF    120
#define uchar unsigned char

int AIN0 = PCF + 0;
int AIN1 = PCF + 1;
int AIN2 = PCF + 2;

//char *state[7] = {"home", "up", "down", "left", "right", "pressed"};

int direction(){
    int x, y, b;
    int tmp;
    x = analogRead(AIN0);
    y = analogRead(AIN1);
    b = analogRead(AIN2);

    if (y == 0)
            tmp = 1; //up
    if (y == 255)
            tmp = 2; //down
    if (x == 255)
            tmp = 3; //left
    if (x == 0)
            tmp = 4; //right
    if (y>=125 && b==0)
            tmp = 5; //button pressed
    if (x-125<15 && x-125>-15 && y-125<15 && y-125>-15 && b==255)
            tmp = 0; //home position

    return tmp;
}

int main(void)
{
    int tmp;
    int status = 0;
    wiringPiSetup();
    //Setup pcf8591 on base pin 120, and address 0x48
    pcf8591Setup(PCF, 0x48);
    while(1) //loop forever
    {
        tmp = direction();
        if (tmp != status)
        {
            switch(tmp)
            {
                case 0: printf("home\n");break;
                case 1: printf("up\n");break;
                case 2: printf("down\n");break;
                case 3: printf("left\n");break;
                case 4: printf("right\n");break;
                case 5: printf("pressed\n");break;
            }
            status = tmp;
        }
    }
    return 0;
}

Python

#!/usr/bin/env python
#---------------------------------------------------
#
#   This is a programe for JoystickPS2 Module.
#
#   This program depend on PCF8591 ADC chip.
#   Follow the instruction book to connect the module and 
#   ADC0832 to your Raspberry Pi.
#
#---------------------------------------------------
import PCF8591 as ADC
import time

def setup():
    ADC.setup(0x48)
    global state

def direction(): #get joystick result
    state = ['home', 'up', 'down', 'left', 'right', 'pressed']
    i = 0

    if ADC.read(0) <= 5:
        i = 1    #up
    if ADC.read(0) >= 250:
        i = 2    #down
    if ADC.read(1) >= 250:
        i = 3    #left
    if ADC.read(1) <= 5:
        i = 4    #right 
    if ADC.read(1)>=250 and ADC.read(2)==0:
        i = 5    #button pressed
    if ADC.read(0)-125 < 15 and ADC.read(0)-125 > -15 and ADC.read(1)-125 < 15 and ADC.read(1)-125 > -15 and ADC.read(2) == 255:
        i = 0 #home

    return state[i]

def loop():
    status = ''
    while True:
        tmp = direction()
        if tmp != None and tmp != status:
            print(tmp)
            status = tmp

def destroy():
    pass

if __name__ == '__main__':
    setup()
    try:
        loop()
    except KeyboardInterrupt:
        destroy()