Add readme

Makefile

@@ -3,6 +3,10 @@
 BOARD_TAG    = leonardo
 MONITOR_PORT = /dev/ttyACM0
 ARDUINO_DIR = /home/dan/projects/arduino-1.8.9
-ARDUINO_LIBS = HID Mouse
+ARDUINO_LIBS = HID Mouse Joystick
+CTAGS_EXEC = /usr/bin/ctags
+CTAGS_OPTS = -e
+ARDMK_DIR = /home/dan/projects/avr/Arduino-Makefile
+
 include /home/dan/projects/avr/Arduino-Makefile/Arduino.mk
 

README.org

@@ -0,0 +1,17 @@
+* What is this?
+This is a simple recipe for turning your Arduino into a usable
+joystick/gamepad.
+
+I am using [[https://robotdyn.com/joystick-shield-for-arduino.html][RobotDyn Joystick shield]] which makes the whole process
+trivial.
+
+* Compiling
+Install the dependencies:
+- [[https://github.com/sudar/Arduino-Makefile][Arduino Makefile]] (available as arduino-mk in Ubuntu/Debiab)
+- [[https://github.com/MHeironimus/ArduinoJoystickLibrary][Arduino Joystick Library]]
+
+Then just run ~make~ and ~make upload~ to flash the board.
+
+* Wiring
+There is nothing to wire -- just pop the shield onto your board and
+plug it in!

joystick.ino

@@ -1,21 +1,51 @@
+/* We use the Joystick library from:
+   <https://github.com/MHeironimus/ArduinoJoystickLibrary> */
+#include <Joystick.h>
 #include <Mouse.h>
 #define DELAY 5
 
-const int sw_pin = 8;
+const int sw_pin = 2;
 const int vrx_pin = A0;
 const int vry_pin = A1;
 
+// UP, RIGHT, DOWN, LEFT, additional left, additional right
+const int btn_count = 6;
+const int btn_pins[] = { 3,4,5,6,7,8 };
+
 const int base_x = 512;
 const int base_y = 519;
 
 const int max_x = 1023;
 const int max_y = 1023;
 
-const int rng = 14;
+
+
+const int rng = 500;
+
+
+int mouse_mode = 0;
+int prev_readings[btn_count];
+
+
+Joystick_ Joystick(JOYSTICK_DEFAULT_REPORT_ID,
+                   JOYSTICK_TYPE_GAMEPAD,
+                   btn_count, // buttons
+                   1, // joystick hat switches
+                   true, // X axis
+                   true, // Y axis
+                   false,  // Z axis
+                   false, false, false, false, false, false, false, false);
 
 void setup() {                
-  pinMode(sw_pin, INPUT_PULLUP);
+  pinMode(sw_pin, INPUT);
+  for (int i = 0; i < btn_count; i++) {
+    pinMode(btn_pins[i], INPUT);
+    prev_readings[i] = 0;
+  }
   Mouse.begin();
+  Joystick.begin();
+  Joystick.setXAxisRange(-rng, rng);
+  Joystick.setYAxisRange(-rng, rng);
 }
 
 int prev_clicked = 0;
@@ -36,17 +66,32 @@ int read_direction(int analog_pin, int base, int max, int rng) {
 }
 
 void loop() {
-  int click = get_clicked();
+  /*int click = get_clicked();
   if (click) {
-    Mouse.click();
+  Mouse.click();}*/
+
+  for (int i = 0; i < btn_count; i++) {
+    int pin = btn_pins[i];
+    int signal = digitalRead(pin);
+    if (signal != prev_readings[i]) {
+      Joystick.setButton(i, signal);
+    }
+    prev_readings[i] = signal;
   }
-  int dirx = read_direction(vrx_pin, base_x, max_x, rng);
+
+  // Analogue input
+  int dirx = -read_direction(vrx_pin, base_x, max_x, rng);
   int diry = read_direction(vry_pin, base_y, max_y, rng);
-  if (diry != 0) {
-    Mouse.move(0, diry, 0);
-  }
-  if (dirx != 0) {
-    Mouse.move(dirx, 0, 0);
+  if (mouse_mode) {
+    if (diry != 0) {
+      Mouse.move(0, diry, 0);
+    }
+    if (dirx != 0) {
+      Mouse.move(dirx, 0, 0);
+    }
+  } else {
+    Joystick.setXAxis (dirx);
+    Joystick.setYAxis (diry);
   }
   
   delay(DELAY);