user_interface.cpp

00001 /*******************************************************************************
00002  * Mangages LCD display, joystick and accelerometer for user interface.
00003  * Bryan Wade
00004  * 27 MAR 2014
00005  ******************************************************************************/
00006 #include "mbed.h"
00007 #include "C12832_lcd.h"
00008 #include "MMA7660.h"
00009 #include "user_interface.h"
00010 #include "effects.h"
00011 
00012 C12832_LCD lcd;
00013 MMA7660 accel(p28, p27, true);
00014 BusIn joystick(p15, p12, p13, p16);
00015 AnalogIn pot(p19);
00016 
00017 static const int STICK_IDLE  = 0;
00018 static const int STICK_UP    = 1;
00019 static const int STICK_DOWN  = 2;
00020 static const int STICK_LEFT  = 4;
00021 static const int STICK_RIGHT = 8;
00022 
00023 static uint8_t stickPrevious;
00024 static effect_mode_t selectedMode;
00025 static char *selectedModeName;
00026 static uint16_t effectGain;
00027 
00028 /*
00029  * Update the display with mode, gain and buffer level.
00030  */
00031 void updateDisplay(int32_t level)
00032 {
00033     lcd.locate(0,0);
00034     lcd.printf("Effect: %s      ", selectedModeName);
00035        
00036     lcd.locate(0,10);
00037     lcd.printf("Intensity: %d    ", effectGain / (MAX_EFFECT_GAIN / 100));
00038     
00039     lcd.locate(0,20);
00040     lcd.printf("Buffer: %d    ", level);
00041 }
00042 
00043 /*
00044  * Get effects mode selected by joystick.
00045  */
00046 void serviceJoystick(void)
00047 {
00048     uint8_t stick = joystick;
00049     
00050     if (stick != stickPrevious) {
00051         stickPrevious = stick;    
00052     
00053         switch (stick)
00054         {
00055         case STICK_UP:
00056             selectedMode = EFFECT_ECHO;
00057             selectedModeName = "Echo";
00058             break;
00059             
00060         case STICK_DOWN:
00061             selectedMode = EFFECT_REVERB;
00062             selectedModeName = "Reverb";
00063             break;
00064             
00065         case STICK_LEFT:
00066         case STICK_RIGHT:
00067             selectedMode = EFFECT_STRAIGHT;
00068             selectedModeName = "Straight";
00069             break;
00070         }    
00071     }
00072 }
00073 
00074 /*
00075  * Get effects gain from accelerometer tilt.
00076  */
00077  void serviceAccel(void)
00078  {
00079      // Tilt sensitivity selected to produce max effect gain 
00080      // at about 80 deg tilt.
00081      static const int32_t TILT_SENSITIVITY = 2750; 
00082      int a[3];
00083      accel.readData(a);
00084      //Convert x-axis raw accelerometer data to the effect gain.
00085      int32_t x = a[0] * TILT_SENSITIVITY;
00086      if (x < 0) x = -x;
00087      if (x > MAX_EFFECT_GAIN) x = MAX_EFFECT_GAIN;
00088      effectGain = (uint16_t)x;    
00089  }
00090  
00091 /*
00092  * Initialize the joystick and display.
00093  */
00094 void UI_Initialize(void)
00095 {
00096     lcd.cls();
00097     stickPrevious = STICK_IDLE;
00098     selectedMode = EFFECT_STRAIGHT;
00099     selectedModeName = "Straight";
00100     effectGain = 0;
00101     // Set the accelerometer to sample slightly
00102     // faster than we poll the user interface.
00103     accel.setSampleRate(32);
00104 }
00105 
00106 /*
00107  * Updates display, joystick and accelerometer
00108  */
00109 void UI_Update(int32_t bufferLevel)
00110 {
00111     serviceJoystick();
00112     serviceAccel();
00113     updateDisplay(bufferLevel);    
00114 }
00115  
00116 
00117 effect_mode_t UI_GetEffectMode(void) { return selectedMode; }
00118 
00119 uint16_t UI_GetEffectGain(void) { return effectGain; }
00120 
00121 
00122