Handles reading and scaling the analog inputs from a simple 2-axis joystick with a pushbutton. Can also attach rise and fall interrupts to the button.
Dependents: joystickdeneme NOKIA_KOMBAT projekat
Purpose
Simple library for reading an analog joystick like those found on game console controllers. These joysticks usually also have a pushbutton.
Example
Joystick Library Example
// Joystick Library Example // // Reads the joystick x axis and fades green and red LEDs in response. // The blue LED is turned on while the pushbutton is pressed. #include "mbed.h" #include <Joystick.h> // target is the KL25Z #define PIN_JOYX PTB0 // A0 #define PIN_JOYY PTB1 // A1 #define PIN_JOYA PTB2 PwmOut led_R(LED1); PwmOut led_G(LED2); PwmOut led_B(LED3); Joystick j(PIN_JOYX, PIN_JOYY, PIN_JOYA); // call on joystick button release void jrise(void) { led_B = 1.0f; } // call on joystick button press void jfall(void) { led_B = 0.0f; } int main () { // setup led_R = 1.0f; led_G = 1.0f; led_B = 1.0f; joypos p; // joystick position // attach joystick button interrupts j.rise(&jrise); j.fall(&jfall); float fade = 0.0f; // loop while (1) { p = j.read(); fade = p.x; if (fade > 0.0) { led_R = 1.0f; led_G = 1.0f - (float)fade; } else if (fade < 0.0) { led_R = 1.0f + (float)fade; led_G = 1.0f; } else { led_R = 1.0f; led_G = 1.0f; } wait(0.01); } }
Joystick.cpp@0:13d10cc6a822, 2015-08-05 (annotated)
- Committer:
- rwunderl
- Date:
- Wed Aug 05 20:21:34 2015 +0000
- Revision:
- 0:13d10cc6a822
Initial commit of the Joystick library.
Who changed what in which revision?
User | Revision | Line number | New contents of line |
---|---|---|---|
rwunderl | 0:13d10cc6a822 | 1 | /* mbed Joystick Library |
rwunderl | 0:13d10cc6a822 | 2 | * Copyright (c) 2015, rwunderl, http://mbed.org |
rwunderl | 0:13d10cc6a822 | 3 | * |
rwunderl | 0:13d10cc6a822 | 4 | * Permission is hereby granted, free of charge, to any person obtaining a copy |
rwunderl | 0:13d10cc6a822 | 5 | * of this software and associated documentation files (the "Software"), to deal |
rwunderl | 0:13d10cc6a822 | 6 | * in the Software without restriction, including without limitation the rights |
rwunderl | 0:13d10cc6a822 | 7 | * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell |
rwunderl | 0:13d10cc6a822 | 8 | * copies of the Software, and to permit persons to whom the Software is |
rwunderl | 0:13d10cc6a822 | 9 | * furnished to do so, subject to the following conditions: |
rwunderl | 0:13d10cc6a822 | 10 | * |
rwunderl | 0:13d10cc6a822 | 11 | * The above copyright notice and this permission notice shall be included in |
rwunderl | 0:13d10cc6a822 | 12 | * all copies or substantial portions of the Software. |
rwunderl | 0:13d10cc6a822 | 13 | * |
rwunderl | 0:13d10cc6a822 | 14 | * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR |
rwunderl | 0:13d10cc6a822 | 15 | * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, |
rwunderl | 0:13d10cc6a822 | 16 | * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE |
rwunderl | 0:13d10cc6a822 | 17 | * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER |
rwunderl | 0:13d10cc6a822 | 18 | * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, |
rwunderl | 0:13d10cc6a822 | 19 | * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN |
rwunderl | 0:13d10cc6a822 | 20 | * THE SOFTWARE. |
rwunderl | 0:13d10cc6a822 | 21 | */ |
rwunderl | 0:13d10cc6a822 | 22 | |
rwunderl | 0:13d10cc6a822 | 23 | #include "Joystick.h" |
rwunderl | 0:13d10cc6a822 | 24 | |
rwunderl | 0:13d10cc6a822 | 25 | // apply the deadzone to the axis extremes (comment if you don't want to use this feature) |
rwunderl | 0:13d10cc6a822 | 26 | #define JOYSTICK_DEADZONE_EXTREMES |
rwunderl | 0:13d10cc6a822 | 27 | |
rwunderl | 0:13d10cc6a822 | 28 | // adjust the deadzone value for your application, if required |
rwunderl | 0:13d10cc6a822 | 29 | const double JOYSTICK_DEADZONE = 0.01; |
rwunderl | 0:13d10cc6a822 | 30 | // set up these constants so they don't have to be calculated every time |
rwunderl | 0:13d10cc6a822 | 31 | #ifdef JOYSTICK_DEADZONE_EXTREMES |
rwunderl | 0:13d10cc6a822 | 32 | const double JOYSTICK_MIN = 0.0 + JOYSTICK_DEADZONE; // effective minimum joystick value |
rwunderl | 0:13d10cc6a822 | 33 | const double JOYSTICK_MINMID = 0.5 - JOYSTICK_DEADZONE; // minimum-side midpoint value |
rwunderl | 0:13d10cc6a822 | 34 | const double JOYSTICK_MAXMID = 0.5 + JOYSTICK_DEADZONE; // maximum-side midpoint value |
rwunderl | 0:13d10cc6a822 | 35 | const double JOYSTICK_MAX = 1.0 - JOYSTICK_DEADZONE; // effective maximum joystick value |
rwunderl | 0:13d10cc6a822 | 36 | #else |
rwunderl | 0:13d10cc6a822 | 37 | const double JOYSTICK_MIN = 0.0; // minimum joystick value |
rwunderl | 0:13d10cc6a822 | 38 | const double JOYSTICK_MINMID = 0.5 - JOYSTICK_DEADZONE; // minimum-side midpoint value |
rwunderl | 0:13d10cc6a822 | 39 | const double JOYSTICK_MAXMID = 0.5 + JOYSTICK_DEADZONE; // maximum-side midpoint value |
rwunderl | 0:13d10cc6a822 | 40 | const double JOYSTICK_MAX = 1.0; // maximum joystick value |
rwunderl | 0:13d10cc6a822 | 41 | #endif |
rwunderl | 0:13d10cc6a822 | 42 | |
rwunderl | 0:13d10cc6a822 | 43 | double _map(double value, double in_min, double in_max, double out_min, double out_max) { |
rwunderl | 0:13d10cc6a822 | 44 | return (value - in_min) * (out_max - out_min) / (in_max - in_min) + out_min; |
rwunderl | 0:13d10cc6a822 | 45 | } |
rwunderl | 0:13d10cc6a822 | 46 | |
rwunderl | 0:13d10cc6a822 | 47 | double _scale(double pos) { |
rwunderl | 0:13d10cc6a822 | 48 | double scaled = 0; |
rwunderl | 0:13d10cc6a822 | 49 | |
rwunderl | 0:13d10cc6a822 | 50 | if (pos < JOYSTICK_MINMID) { |
rwunderl | 0:13d10cc6a822 | 51 | scaled = _map(pos, JOYSTICK_MIN, JOYSTICK_MINMID, -1, 0); |
rwunderl | 0:13d10cc6a822 | 52 | } else if (pos > JOYSTICK_MAXMID) { |
rwunderl | 0:13d10cc6a822 | 53 | scaled = _map(pos, JOYSTICK_MAXMID, JOYSTICK_MAX, 0, 1); |
rwunderl | 0:13d10cc6a822 | 54 | } |
rwunderl | 0:13d10cc6a822 | 55 | |
rwunderl | 0:13d10cc6a822 | 56 | // check out of bounds [-1.0, 1.0] (happens at the extremes) |
rwunderl | 0:13d10cc6a822 | 57 | if (scaled < -1) { |
rwunderl | 0:13d10cc6a822 | 58 | scaled = -1; |
rwunderl | 0:13d10cc6a822 | 59 | } else if (scaled > 1) { |
rwunderl | 0:13d10cc6a822 | 60 | scaled = 1; |
rwunderl | 0:13d10cc6a822 | 61 | } |
rwunderl | 0:13d10cc6a822 | 62 | |
rwunderl | 0:13d10cc6a822 | 63 | return scaled; |
rwunderl | 0:13d10cc6a822 | 64 | } |
rwunderl | 0:13d10cc6a822 | 65 | |
rwunderl | 0:13d10cc6a822 | 66 | Joystick::Joystick(PinName x, PinName y, PinName a) : _x(x), _y(y), _a(a) { |
rwunderl | 0:13d10cc6a822 | 67 | } |
rwunderl | 0:13d10cc6a822 | 68 | |
rwunderl | 0:13d10cc6a822 | 69 | joypos Joystick::read() { |
rwunderl | 0:13d10cc6a822 | 70 | joypos pos; |
rwunderl | 0:13d10cc6a822 | 71 | |
rwunderl | 0:13d10cc6a822 | 72 | pos.x = getX(); |
rwunderl | 0:13d10cc6a822 | 73 | pos.y = getY(); |
rwunderl | 0:13d10cc6a822 | 74 | |
rwunderl | 0:13d10cc6a822 | 75 | return pos; |
rwunderl | 0:13d10cc6a822 | 76 | } |
rwunderl | 0:13d10cc6a822 | 77 | |
rwunderl | 0:13d10cc6a822 | 78 | double Joystick::getX() { |
rwunderl | 0:13d10cc6a822 | 79 | double val = _x.read(); |
rwunderl | 0:13d10cc6a822 | 80 | val = _scale(val); |
rwunderl | 0:13d10cc6a822 | 81 | return val; |
rwunderl | 0:13d10cc6a822 | 82 | } |
rwunderl | 0:13d10cc6a822 | 83 | |
rwunderl | 0:13d10cc6a822 | 84 | double Joystick::getY() { |
rwunderl | 0:13d10cc6a822 | 85 | double val = _y.read(); |
rwunderl | 0:13d10cc6a822 | 86 | val = _scale(val); |
rwunderl | 0:13d10cc6a822 | 87 | return val; |
rwunderl | 0:13d10cc6a822 | 88 | } |
rwunderl | 0:13d10cc6a822 | 89 | |
rwunderl | 0:13d10cc6a822 | 90 | double Joystick::getRawX() { |
rwunderl | 0:13d10cc6a822 | 91 | return _x.read(); |
rwunderl | 0:13d10cc6a822 | 92 | } |
rwunderl | 0:13d10cc6a822 | 93 | |
rwunderl | 0:13d10cc6a822 | 94 | double Joystick::getRawY() { |
rwunderl | 0:13d10cc6a822 | 95 | return _y.read(); |
rwunderl | 0:13d10cc6a822 | 96 | } |
rwunderl | 0:13d10cc6a822 | 97 | |
rwunderl | 0:13d10cc6a822 | 98 | void Joystick::rise(void (*fptr)(void)) { |
rwunderl | 0:13d10cc6a822 | 99 | _a.rise(fptr); |
rwunderl | 0:13d10cc6a822 | 100 | } |
rwunderl | 0:13d10cc6a822 | 101 | |
rwunderl | 0:13d10cc6a822 | 102 | void Joystick::fall(void (*fptr)(void)) { |
rwunderl | 0:13d10cc6a822 | 103 | _a.fall(fptr); |
rwunderl | 0:13d10cc6a822 | 104 | } |