drivers/sensors/analogjoystick/analogjoystick.c

   1 /**************************************************************************/
   2 /*!
   3     @file     analogjoystick.c
   4     @author   K. Townsend (microBuilder.eu)
   5
   6     @section DESCRIPTION
   7
   8     Driver for a simple four-way analog joystick.
   9
  10     @section Example
  11
  12     @code
  13     @endcode
  14
  15     @section LICENSE
  16
  17     Software License Agreement (BSD License)
  18
  19     Copyright (c) 2010, microBuilder SARL
  20     All rights reserved.
  21
  22     Redistribution and use in source and binary forms, with or without
  23     modification, are permitted provided that the following conditions are met:
  24     1. Redistributions of source code must retain the above copyright
  25     notice, this list of conditions and the following disclaimer.
  26     2. Redistributions in binary form must reproduce the above copyright
  27     notice, this list of conditions and the following disclaimer in the
  28     documentation and/or other materials provided with the distribution.
  29     3. Neither the name of the copyright holders nor the
  30     names of its contributors may be used to endorse or promote products
  31     derived from this software without specific prior written permission.
  32
  33     THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS ''AS IS'' AND ANY
  34     EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
  35     WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
  36     DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER BE LIABLE FOR ANY
  37     DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
  38     (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
  39     LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
  40     ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  41     (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
  42     SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  43 */
  44 /**************************************************************************/
  45 #include "analogjoystick.h"
  46 #include "core/adc/adc.h"
  47 #include "core/gpio/gpio.h"
  48
  49 static bool _joystickInitialised = false;
  50
  51 /**************************************************************************/
  52 /*!
  53     @brief  Initialises the analog joystick, setting the appropriate
  54             pins to analog and digital input.
  55 */
  56 /**************************************************************************/
  57 void joystickInit(void)
  58 {
  59   // Make sure SEL is set to GPIO and input
  60   JOYSTICK_SEL_FUNC_GPIO;
  61   gpioSetDir (JOYSTICK_SEL_PORT, JOYSTICK_SEL_PIN, 0);
  62
  63   // Make sure that ADC is initialised
  64   adcInit();
  65
  66   // Set HORIZ/VERT pins to ADC
  67   JOYSTICK_VERT_FUNC_ADC;
  68   JOYSTICK_HORIZ_FUNC_ADC;
  69
  70   _joystickInitialised = true;
  71 }
  72
  73 /**************************************************************************/
  74 /*!
  75     @brief  Gets the raw ADC values for the horizontal and vertical
  76             axis, as well as the current state of the select button.
  77
  78     @param[out] horizontal
  79                 pointer to the uint32_t variable that will hold the
  80                 results of the horizontal analog conversion
  81     @param[out] vertical
  82                 pointer to the uint32_t variable that will hold the
  83                 results of the vertical analog conversion
  84     @param[out] select
  85                 pointer to the bool variable that will hold the
  86                 current state of the digital select button
  87 */
  88 /**************************************************************************/
  89 void joystickGetValues(uint32_t *horizontal, uint32_t *vertical, bool *select)
  90 {
  91   if (!_joystickInitialised) joystickInit();
  92
  93   // Get current ADC values
  94   *horizontal = adcRead(JOYSTICK_HORIZ_ADCPORT);
  95   *vertical = adcRead(JOYSTICK_VERT_ADCPORT);
  96   *select = gpioGetValue(JOYSTICK_SEL_PORT, JOYSTICK_SEL_PIN);
  97 }
  98
  99 /**************************************************************************/
 100 /*!
 101     @brief  Gets the rough direction that the joystick is currently
 102             positioned at
 103
 104     @param[out] direction
 105                 The joystick_direction_t (enum) that will be used to
 106                 identify the joysticks approximate current direction.
 107 */
 108 /**************************************************************************/
 109 void joystickGetDirection(joystick_direction_t *direction)
 110 {
 111   if (!_joystickInitialised) joystickInit();
 112
 113   uint32_t hor, ver;
 114   bool sel;
 115
 116   // Get current joystick position
 117   joystickGetValues(&hor, &ver, &sel);
 118
 119   // ToDo: Process values
 120   direction = JOYSTICK_DIR_NONE;
 121 }
 122
 123 /**************************************************************************/
 124 /*!
 125     @brief  Get the approximate rotation of the joystick from 0-359° in
 126             a clock-wise direction.
 127
 128     @param[out] rotation
 129                 Pointer to the uint32_t variable that will hold the
 130                 rotation value.
 131 */
 132 /**************************************************************************/
 133 void joystickGetRotation(uint32_t *rotation)
 134 {
 135   if (!_joystickInitialised) joystickInit();
 136
 137   // ToDo
 138 }