MCUME/MCUME_teensy/teensync/emuapi.cpp

#include <Arduino.h>
  
//extern "C" {
  #include "emuapi.h"
  #include "iopins.h"
//}


void emu_init(void)
{
  emu_InitJoysticks();
}


void emu_printf(char * text)
{
  Serial.println(text);
}

void emu_printf(int val)
{
  Serial.println(val);
}

void emu_printi(int val)
{
  Serial.println(val);
}

void * emu_Malloc(int size)
{
  void * retval =  malloc(size);
  if (!retval) {
    emu_printf("failled to allocate ");
    emu_printf(size);
  }
  else {
    emu_printf("could allocate ");
    emu_printf(size);    
  }
  
  return retval;
}

void emu_Free(void * pt)
{
  free(pt);
}



static int keypadval=0; 
static boolean joySwapped = false;
static uint16_t bLastState;
static int xRef;
static int yRef;


int emu_ReadAnalogJoyX(int min, int max) 
{
  int val = analogRead(PIN_JOY2_A1X);
#if INVX
  val = 4095 - val;
#endif
  val = val-xRef;
  val = ((val*140)/100);
  if ( (val > -512) && (val < 512) ) val = 0;
  val = val+2048;
  return (val*(max-min))/4096;
}

int emu_ReadAnalogJoyY(int min, int max) 
{
  int val = analogRead(PIN_JOY2_A2Y);
#if INVY
  val = 4095 - val;
#endif
  val = val-yRef;
  val = ((val*120)/100);
  if ( (val > -512) && (val < 512) ) val = 0;
  //val = (val*(max-min))/4096;
  val = val+2048;
  //return val+(max-min)/2;
  return (val*(max-min))/4096;
}


static uint16_t readAnalogJoystick(void)
{
  uint16_t joysval = 0;

  int xReading = emu_ReadAnalogJoyX(0,256);
  if (xReading > 128) joysval |= MASK_JOY2_LEFT;
  else if (xReading < 128) joysval |= MASK_JOY2_RIGHT;
  
  int yReading = emu_ReadAnalogJoyY(0,256);
  if (yReading < 128) joysval |= MASK_JOY2_UP;
  else if (yReading > 128) joysval |= MASK_JOY2_DOWN;
  
#ifdef PIN_JOY2_BTN  
  joysval |= (digitalRead(PIN_JOY2_BTN) == HIGH ? 0 : MASK_JOY2_BTN);
#endif
  return (joysval);     
}


int emu_SwapJoysticks(int statusOnly) {
  if (!statusOnly) {
    if (joySwapped) {
      joySwapped = false;
    }
    else {
      joySwapped = true;
    }
  }
  return(joySwapped?1:0);
}

int emu_GetPad(void) 
{
  return(keypadval/*|((joySwapped?1:0)<<7)*/);
}

int emu_ReadKeys(void) 
{
  uint16_t retval;
  uint16_t j1 = readAnalogJoystick();
  uint16_t j2 = 0;
  
  // Second joystick
#ifdef PIN_JOY1_1
  if ( digitalRead(PIN_JOY1_1) == LOW ) j2 |= MASK_JOY2_UP;
#endif
#ifdef PIN_JOY1_2
  if ( digitalRead(PIN_JOY1_2) == LOW ) j2 |= MASK_JOY2_DOWN;
#endif
#ifdef PIN_JOY1_3
  if ( digitalRead(PIN_JOY1_3) == LOW ) j2 |= MASK_JOY2_RIGHT;
#endif
#ifdef PIN_JOY1_4
  if ( digitalRead(PIN_JOY1_4) == LOW ) j2 |= MASK_JOY2_LEFT;
#endif
#ifdef PIN_JOY1_BTN
  if ( digitalRead(PIN_JOY1_BTN) == LOW ) j2 |= MASK_JOY2_BTN;
#endif
  if (joySwapped) {
    retval = ((j1 << 8) | j2);
  }
  else {
    retval = ((j2 << 8) | j1);
  }

#ifdef PIN_KEY_USER1 
  if ( digitalRead(PIN_KEY_USER1) == LOW ) retval |= MASK_KEY_USER1;
#endif
#ifdef PIN_KEY_USER2 
  if ( digitalRead(PIN_KEY_USER2) == LOW ) retval |= MASK_KEY_USER2;
#endif
#ifdef PIN_KEY_USER3 
  if ( digitalRead(PIN_KEY_USER3) == LOW ) retval |= MASK_KEY_USER3;
#endif
#ifdef PIN_KEY_USER4 
  if ( digitalRead(PIN_KEY_USER4) == LOW ) retval |= MASK_KEY_USER4;
#endif

  //Serial.println(retval,HEX);

  return (retval);
}

unsigned short emu_DebounceLocalKeys(void)
{
  uint16_t bCurState = emu_ReadKeys();
  uint16_t bClick = bCurState & ~bLastState;
  bLastState = bCurState;

  return (bClick);
}


void emu_InitJoysticks(void) { 

  // Second Joystick   
#ifdef PIN_JOY1_1
  pinMode(PIN_JOY1_1, INPUT_PULLUP);
#endif  
#ifdef PIN_JOY1_2
  pinMode(PIN_JOY1_2, INPUT_PULLUP);
#endif  
#ifdef PIN_JOY1_3
  pinMode(PIN_JOY1_3, INPUT_PULLUP);
#endif  
#ifdef PIN_JOY1_4
  pinMode(PIN_JOY1_4, INPUT_PULLUP);
#endif  
#ifdef PIN_JOY1_BTN
  pinMode(PIN_JOY1_BTN, INPUT_PULLUP);
#endif  

#ifdef PIN_KEY_USER1
  pinMode(PIN_KEY_USER1, INPUT_PULLUP);
#endif  
#ifdef PIN_KEY_USER2
  pinMode(PIN_KEY_USER2, INPUT_PULLUP);
#endif  
#ifdef PIN_KEY_USER3
  pinMode(PIN_KEY_USER3, INPUT_PULLUP);
#endif  
#ifdef PIN_KEY_USER4
  pinMode(PIN_KEY_USER4, INPUT_PULLUP);
#endif  
#ifdef PIN_JOY2_BTN
  pinMode(PIN_JOY2_BTN, INPUT_PULLUP);
#endif  
  analogReadResolution(12);
  xRef=0; yRef=0;
  for (int i=0; i<10; i++) {
    xRef += analogRead(PIN_JOY2_A1X);
    yRef += analogRead(PIN_JOY2_A2Y);  
    delay(20);
  }

#if INVX
  xRef = 4095 -xRef/10;
#else
  xRef /= 10;
#endif
#if INVY
  yRef = 4095 -yRef/10;
#else
  yRef /= 10;
#endif   
}