Freenove Ultimate Starter Kit - Page 137

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Chapter 12 Joystick
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Code
In this project code, we will read ADC value of X and Y axis of Joystick, and read digital quality of Z axis, then
print these data out.
C Code 12.1.1 Joystick
First observe the project result, and then analyze the code.
1. Use cd command to enter 12.1.1_Joystick directory of C code.
cd ~/Freenove_Ultimate_Starter_Kit_for_Raspberry_Pi/Code/C_Code/12.1.1_ Joystick
2. Use following command to compile "Joystick.c" and generate executable file "Joystick.c". "-lm" option is
needed.
gcc Joystick.c -o Joystick -lwiringPi -lm
3. Then run the generated file "Joystick".
sudo ./Joystick
After Program is executed, the terminal window will print out the data of 3 axes X, Y, Z. And shifting the
Joystick or pressing it will make those data change.
The flowing is the code:
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#include <wiringPi.h>
#include <pcf8591.h>
#include <stdio.h>
#include <softPwm.h>
#define address 0x48 //pcf8591 default address
#define pinbase 64 //any number above 64
#define A0 pinbase + 0
#define A1 pinbase + 1
#define A2 pinbase + 2
#define A3 pinbase + 3
#define Z_Pin 1 //define pin for axis Z
int main(void){
int val_X,val_Y,val_Z;
if(wiringPiSetup() == -1){ //when initialize wiring failed,print message to screen