cartreader/Cart_Reader/Cart_Reader.ino

/**********************************************************************************
                    Cartridge Reader for Arduino Mega2560

   This project represents a community-driven effort to provide
   an easy to build and easy to modify cartridge dumper.

   Date:             2024-07-08
   Version:          14.0

   SD lib: https://github.com/greiman/SdFat
   LCD lib: https://github.com/olikraus/u8g2
   Neopixel lib: https://github.com/adafruit/Adafruit_NeoPixel
   Rotary Enc lib: https://github.com/mathertel/RotaryEncoder
   SI5351 lib: https://github.com/etherkit/Si5351Arduino
   RTC lib: https://github.com/adafruit/RTClib
   Frequency lib: https://github.com/PaulStoffregen/FreqCount

   Compiled with Arduino IDE 2.2.1

   Thanks to:
   MichlK - ROM Reader for Super Nintendo
   Jeff Saltzman - 4-Way Button
   Wayne and Layne - Video Game Shield menu
   skaman - Cart ROM READER SNES ENHANCED, Famicom Cart Dumper, 2600, 5200, 7800, ARC, ATARI8, BALLY, C64, COLV, FAIRCHILD, 
   INTV, LEAP, LJ, LJPRO, MSX, ODY2, PCW, POKEMINI, PV1000, PYUUTA, RCA, TI99, TRS80, VBOY, VECTREX, WSV, VIC20, VSMILE modules
   Tamanegi_taro - PCE and Satellaview modules
   splash5 - GBSmart, Wonderswan, NGP and Super A'can modules
   partlyhuman - Casio Loopy & Atari Lynx module
   hkz & themanbehindthecurtain - N64 flashram commands
   Andrew Brown & Peter Den Hartog - N64 controller protocol
   libdragon - N64 controller checksum functions
   Angus Gratton - CRC32
   Snes9x - SuperFX sram fix
   insidegadgets - GBCartRead
   RobinTheHood - GameboyAdvanceRomDumper
   Gens-gs - Megadrive checksum
   fceux - iNes header
   PsyK0p4T - Sufami Turbo module
   LuigiBlood - SNES Game Processor RAM Cassette module

   And a special Thank You to all coders and contributors on Github and the Arduino forum:
   jiyunomegami, splash5, Kreeblah, ramapcsx2, PsyK0p4T, Dakkaron, majorpbx, Pickle, sdhizumi,
   Uzlopak, sakman55, Tombo89, scrap-a, borti4938, vogelfreiheit, CaitSith2, Modman, Chomemel, 
   philenotfound, karimhadjsalem, nsx0r, ducky92, niklasweber, Lesserkuma, BacteriaMage, qufb,
   vpelletier, Ancyker, mattiacci, RWeick, ButThouMust, partlyhuman, fakkuyuu, hxlnt, breyell,
   smesgr9000, joshman196, PsychoFox11, plaidpants, LuigiBlood, InvalidInterrupt

   And to nocash for figuring out the secrets of the SFC Nintendo Power cartridge.

   This program is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation, either version 3 of the License, or
   (at your option) any later version.

   This program is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License for more details.

   You should have received a copy of the GNU General Public License
   along with this program.  If not, see <https://www.gnu.org/licenses/>.

**********************************************************************************/

#include "OSCR.h"

/******************************************
   Libraries
 *****************************************/

// SD Card
SdFs sd;
FsFile myFile;
#ifdef ENABLE_GLOBAL_LOG
FsFile myLog;
bool dont_log = false;
#endif

// AVR Eeprom
#include <EEPROM.h>
// forward declarations for "T" (for non Arduino IDE)
template<class T> int EEPROM_writeAnything(int ee, const T& value);
template<class T> int EEPROM_readAnything(int ee, T& value);

// Graphic SPI LCD
#ifdef ENABLE_LCD
#include <U8g2lib.h>
U8G2_ST7567_OS12864_F_4W_HW_SPI display(U8G2_R2, /* cs=*/12, /* dc=*/11, /* reset=*/10);
#endif

// Rotary Encoder
#ifdef ENABLE_ROTARY
#include <RotaryEncoder.h>
#define PIN_IN1 18
#define PIN_IN2 19
#ifdef rotate_counter_clockwise
RotaryEncoder encoder(PIN_IN2, PIN_IN1, RotaryEncoder::LatchMode::FOUR3);
#else
RotaryEncoder encoder(PIN_IN1, PIN_IN2, RotaryEncoder::LatchMode::FOUR3);
#endif
int rotaryPos = 0;
#endif

// Choose RGB LED type
#ifdef ENABLE_NEOPIXEL
// Neopixel
#include <Adafruit_NeoPixel.h>
Adafruit_NeoPixel pixels(3, 13, NEO_GRB + NEO_KHZ800);
#endif

typedef enum COLOR_T {
  blue_color,
  red_color,
  purple_color,
  green_color,
  turquoise_color,
  yellow_color,
  white_color,
  black_color,
} color_t;

// Graphic I2C OLED
#ifdef ENABLE_OLED
#include <U8g2lib.h>
U8G2_SSD1306_128X64_NONAME_F_HW_I2C display(U8G2_R0, /* reset=*/U8X8_PIN_NONE);
#endif

// Adafruit Clock Generator
#include <si5351.h>
Si5351 clockgen;
bool i2c_found;

// RTC Library
#ifdef ENABLE_RTC
#define _RTC_H
#include "RTClib.h"
#endif

// Clockgen Calibration
#ifdef OPTION_CLOCKGEN_CALIBRATION
#include "FreqCount.h"
#endif

void _print_FatalError(void) __attribute__((noreturn));
void print_FatalError(const __FlashStringHelper* errorMessage) __attribute__((noreturn));
void print_FatalError(byte errorMessage) __attribute__((noreturn));

/******************************************
  End of inclusions and forward declarations
 *****************************************/

template<class T> int EEPROM_writeAnything(int ee, const T& value) {
  const byte* p = (const byte*)(const void*)&value;
  unsigned int i;
  for (i = 0; i < sizeof(value); i++)
    EEPROM.write(ee++, *p++);
  return i;
}

template<class T> int EEPROM_readAnything(int ee, T& value) {
  byte* p = (byte*)(void*)&value;
  unsigned int i;
  for (i = 0; i < sizeof(value); i++)
    *p++ = EEPROM.read(ee++);
  return i;
}

/******************************************
  Common Strings
 *****************************************/
#define press_button_STR 0
#define sd_error_STR 1
#define reset_STR 2
#define did_not_verify_STR 3
#define _bytes_STR 4
#define error_STR 5
#define create_file_STR 6
#define open_file_STR 7
#define file_too_big_STR 8
#define done_STR 9
#define saving_to_STR 10
#define verifying_STR 11
#define flashing_file_STR 12
#define press_to_change_STR 13
#define right_to_select_STR 14
#define rotate_to_change_STR 15
#define press_to_select_STR 16

// This array holds the most often used strings
constexpr char string_press_button0[] PROGMEM = "Press Button...";
constexpr char string_sd_error1[] PROGMEM = "SD Error";
constexpr char string_did_not_verify3[] PROGMEM = "did not verify";
constexpr char string_bytes4[] PROGMEM = " bytes ";
constexpr char string_error5[] PROGMEM = "Error: ";
constexpr char string_create_file6[] PROGMEM = "Can't create file";
constexpr char string_open_file7[] PROGMEM = "Can't open file";
constexpr char string_file_too_big8[] PROGMEM = "File too big";
constexpr char string_done9[] PROGMEM = "Done";
constexpr char string_saving_to10[] PROGMEM = "Saving to ";
constexpr char string_verifying11[] PROGMEM = "Verifying...";
constexpr char string_flashing_file12[] PROGMEM = "Flashing file ";
constexpr char string_press_to_change13[] PROGMEM = "Press left to Change";
constexpr char string_right_to_select14[] PROGMEM = "and right to Select";
constexpr char string_rotate_to_change15[] PROGMEM = "Rotate to Change";
constexpr char string_press_to_select16[] PROGMEM = "Press to Select";

static const char* const string_table[] PROGMEM = { string_press_button0, string_sd_error1, FSTRING_RESET, string_did_not_verify3, string_bytes4, string_error5, string_create_file6, string_open_file7, string_file_too_big8, string_done9, string_saving_to10, string_verifying11, string_flashing_file12, string_press_to_change13, string_right_to_select14, string_rotate_to_change15, string_press_to_select16 };

void print_STR(byte string_number, boolean newline) {
  char string_buffer[22];
  strcpy_P(string_buffer, (char*)pgm_read_word(&(string_table[string_number])));
  if (newline)
    println_Msg(string_buffer);
  else
    print_Msg(string_buffer);
}

/******************************************
  Defines
 *****************************************/

// optimization-safe nop delay
#define NOP __asm__ __volatile__("nop\n\t")

// Button timing
#define debounce 20        // ms debounce period to prevent flickering when pressing or releasing the button
#define DCgap 250          // max ms between clicks for a double click event
#define holdTime 2000      // ms hold period: how long to wait for press+hold event
#define longHoldTime 5000  // ms long hold period: how long to wait for press+hold event

/******************************************
   Variables
 *****************************************/
#ifdef ENABLE_ROTARY
// Button debounce
boolean buttonState = HIGH;          // the current reading from the input pin
boolean lastButtonState = HIGH;      // the previous reading from the input pin
unsigned long lastDebounceTime = 0;  // the last time the output pin was toggled
unsigned long debounceDelay = 50;    // the debounce time; increase if the output flickers
#endif

#ifdef ENABLE_OLED
// Button 1
boolean buttonVal1 = HIGH;           // value read from button
boolean buttonLast1 = HIGH;          // buffered value of the button's previous state
boolean DCwaiting1 = false;          // whether we're waiting for a double click (down)
boolean DConUp1 = false;             // whether to register a double click on next release, or whether to wait and click
boolean singleOK1 = true;            // whether it's OK to do a single click
long downTime1 = -1;                 // time the button was pressed down
long upTime1 = -1;                   // time the button was released
boolean ignoreUp1 = false;           // whether to ignore the button release because the click+hold was triggered
boolean waitForUp1 = false;          // when held, whether to wait for the up event
boolean holdEventPast1 = false;      // whether or not the hold event happened already
boolean longholdEventPast1 = false;  // whether or not the long hold event happened already
// Button 2
boolean buttonVal2 = HIGH;           // value read from button
boolean buttonLast2 = HIGH;          // buffered value of the button's previous state
boolean DCwaiting2 = false;          // whether we're waiting for a double click (down)
boolean DConUp2 = false;             // whether to register a double click on next release, or whether to wait and click
boolean singleOK2 = true;            // whether it's OK to do a single click
long downTime2 = -1;                 // time the button was pressed down
long upTime2 = -1;                   // time the button was released
boolean ignoreUp2 = false;           // whether to ignore the button release because the click+hold was triggered
boolean waitForUp2 = false;          // when held, whether to wait for the up event
boolean holdEventPast2 = false;      // whether or not the hold event happened already
boolean longholdEventPast2 = false;  // whether or not the long hold event happened already
#endif

#ifdef ENABLE_SERIAL
// For incoming serial data
int incomingByte;
#endif

// Variables for the menu
int choice = 0;
// Temporary array that holds the menu option read out of progmem
char menuOptions[7][20];
boolean ignoreError = 0;

// File browser
#define FILENAME_LENGTH 100
#define FILEPATH_LENGTH 132
#define FILEOPTS_LENGTH 20

char fileName[FILENAME_LENGTH];
char filePath[FILEPATH_LENGTH];
byte currPage;
byte lastPage;
byte numPages;
boolean root = 0;
boolean filebrowse = 0;

// Common
// 21 chars for ROM name, one char for termination
char romName[22];
unsigned long sramSize = 0;
int romType = 0;
byte saveType;
word romSize = 0;
word numBanks = 128;
char checksumStr[9];
bool errorLvl = 0;
byte romVersion = 0;
char cartID[5];
unsigned long cartSize;
unsigned int flashid;
char flashid_str[5];
char vendorID[5];
unsigned long fileSize;
unsigned long sramBase;
unsigned long flashBanks;
bool flashX16Mode;
bool flashSwitchLastBits;

// Variable to count errors
unsigned long writeErrors;

// Operation mode
CORES mode = CORE_MAX;

//remember folder number to create a new folder for every game
int foldern;
// 4 chars for console type, 4 chars for SAVE/ROM, 21 chars for ROM name, 4 chars for folder number, 3 chars for slashes, one char for termination, one char savety
char folder[38];

// Array that holds the data
byte sdBuffer[512];

// soft reset Arduino: jumps to 0
// using the watchdog timer would be more elegant but some Mega2560 bootloaders are buggy with it
void (*resetArduino)(void) __attribute__((noreturn)) = 0;

// Progressbar
void draw_progressbar(uint32_t processedsize, uint32_t totalsize);

// used by MD and NES modules
byte eepbit[8];
byte eeptemp;

// Array to hold iNES header
byte iNES_HEADER[16];
//ID 0-3
//ROM_size 4
//VROM_size 5
//ROM_type 6
//ROM_type2 7
//ROM_type3 8
//Upper_ROM_VROM_size 9
//RAM_size 10
//VRAM_size 11
//TV_system 12
//VS_hardware 13
//reserved 14, 15

//******************************************
// CRC32
//******************************************
// CRC32 lookup table // 256 entries
constexpr uint32_t crc_32_tab[] PROGMEM = { /* CRC polynomial 0xedb88320 */
                                            0x00000000, 0x77073096, 0xee0e612c, 0x990951ba, 0x076dc419, 0x706af48f,
                                            0xe963a535, 0x9e6495a3, 0x0edb8832, 0x79dcb8a4, 0xe0d5e91e, 0x97d2d988,
                                            0x09b64c2b, 0x7eb17cbd, 0xe7b82d07, 0x90bf1d91, 0x1db71064, 0x6ab020f2,
                                            0xf3b97148, 0x84be41de, 0x1adad47d, 0x6ddde4eb, 0xf4d4b551, 0x83d385c7,
                                            0x136c9856, 0x646ba8c0, 0xfd62f97a, 0x8a65c9ec, 0x14015c4f, 0x63066cd9,
                                            0xfa0f3d63, 0x8d080df5, 0x3b6e20c8, 0x4c69105e, 0xd56041e4, 0xa2677172,
                                            0x3c03e4d1, 0x4b04d447, 0xd20d85fd, 0xa50ab56b, 0x35b5a8fa, 0x42b2986c,
                                            0xdbbbc9d6, 0xacbcf940, 0x32d86ce3, 0x45df5c75, 0xdcd60dcf, 0xabd13d59,
                                            0x26d930ac, 0x51de003a, 0xc8d75180, 0xbfd06116, 0x21b4f4b5, 0x56b3c423,
                                            0xcfba9599, 0xb8bda50f, 0x2802b89e, 0x5f058808, 0xc60cd9b2, 0xb10be924,
                                            0x2f6f7c87, 0x58684c11, 0xc1611dab, 0xb6662d3d, 0x76dc4190, 0x01db7106,
                                            0x98d220bc, 0xefd5102a, 0x71b18589, 0x06b6b51f, 0x9fbfe4a5, 0xe8b8d433,
                                            0x7807c9a2, 0x0f00f934, 0x9609a88e, 0xe10e9818, 0x7f6a0dbb, 0x086d3d2d,
                                            0x91646c97, 0xe6635c01, 0x6b6b51f4, 0x1c6c6162, 0x856530d8, 0xf262004e,
                                            0x6c0695ed, 0x1b01a57b, 0x8208f4c1, 0xf50fc457, 0x65b0d9c6, 0x12b7e950,
                                            0x8bbeb8ea, 0xfcb9887c, 0x62dd1ddf, 0x15da2d49, 0x8cd37cf3, 0xfbd44c65,
                                            0x4db26158, 0x3ab551ce, 0xa3bc0074, 0xd4bb30e2, 0x4adfa541, 0x3dd895d7,
                                            0xa4d1c46d, 0xd3d6f4fb, 0x4369e96a, 0x346ed9fc, 0xad678846, 0xda60b8d0,
                                            0x44042d73, 0x33031de5, 0xaa0a4c5f, 0xdd0d7cc9, 0x5005713c, 0x270241aa,
                                            0xbe0b1010, 0xc90c2086, 0x5768b525, 0x206f85b3, 0xb966d409, 0xce61e49f,
                                            0x5edef90e, 0x29d9c998, 0xb0d09822, 0xc7d7a8b4, 0x59b33d17, 0x2eb40d81,
                                            0xb7bd5c3b, 0xc0ba6cad, 0xedb88320, 0x9abfb3b6, 0x03b6e20c, 0x74b1d29a,
                                            0xead54739, 0x9dd277af, 0x04db2615, 0x73dc1683, 0xe3630b12, 0x94643b84,
                                            0x0d6d6a3e, 0x7a6a5aa8, 0xe40ecf0b, 0x9309ff9d, 0x0a00ae27, 0x7d079eb1,
                                            0xf00f9344, 0x8708a3d2, 0x1e01f268, 0x6906c2fe, 0xf762575d, 0x806567cb,
                                            0x196c3671, 0x6e6b06e7, 0xfed41b76, 0x89d32be0, 0x10da7a5a, 0x67dd4acc,
                                            0xf9b9df6f, 0x8ebeeff9, 0x17b7be43, 0x60b08ed5, 0xd6d6a3e8, 0xa1d1937e,
                                            0x38d8c2c4, 0x4fdff252, 0xd1bb67f1, 0xa6bc5767, 0x3fb506dd, 0x48b2364b,
                                            0xd80d2bda, 0xaf0a1b4c, 0x36034af6, 0x41047a60, 0xdf60efc3, 0xa867df55,
                                            0x316e8eef, 0x4669be79, 0xcb61b38c, 0xbc66831a, 0x256fd2a0, 0x5268e236,
                                            0xcc0c7795, 0xbb0b4703, 0x220216b9, 0x5505262f, 0xc5ba3bbe, 0xb2bd0b28,
                                            0x2bb45a92, 0x5cb36a04, 0xc2d7ffa7, 0xb5d0cf31, 0x2cd99e8b, 0x5bdeae1d,
                                            0x9b64c2b0, 0xec63f226, 0x756aa39c, 0x026d930a, 0x9c0906a9, 0xeb0e363f,
                                            0x72076785, 0x05005713, 0x95bf4a82, 0xe2b87a14, 0x7bb12bae, 0x0cb61b38,
                                            0x92d28e9b, 0xe5d5be0d, 0x7cdcefb7, 0x0bdbdf21, 0x86d3d2d4, 0xf1d4e242,
                                            0x68ddb3f8, 0x1fda836e, 0x81be16cd, 0xf6b9265b, 0x6fb077e1, 0x18b74777,
                                            0x88085ae6, 0xff0f6a70, 0x66063bca, 0x11010b5c, 0x8f659eff, 0xf862ae69,
                                            0x616bffd3, 0x166ccf45, 0xa00ae278, 0xd70dd2ee, 0x4e048354, 0x3903b3c2,
                                            0xa7672661, 0xd06016f7, 0x4969474d, 0x3e6e77db, 0xaed16a4a, 0xd9d65adc,
                                            0x40df0b66, 0x37d83bf0, 0xa9bcae53, 0xdebb9ec5, 0x47b2cf7f, 0x30b5ffe9,
                                            0xbdbdf21c, 0xcabac28a, 0x53b39330, 0x24b4a3a6, 0xbad03605, 0xcdd70693,
                                            0x54de5729, 0x23d967bf, 0xb3667a2e, 0xc4614ab8, 0x5d681b02, 0x2a6f2b94,
                                            0xb40bbe37, 0xc30c8ea1, 0x5a05df1b, 0x2d02ef8d
};

// Defined as a macros, as compiler disregards inlining requests and these are
// performance-critical functions.
#define UPDATE_CRC(crc, ch) \
  do { \
    uint8_t idx = ((crc) ^ (ch)) & 0xff; \
    uint32_t tab_value = pgm_read_dword(crc_32_tab + idx); \
    (crc) = tab_value ^ ((crc) >> 8); \
  } while (0)

uint32_t updateCRC(const byte* buffer, size_t length, uint32_t crc) {
  for (size_t c = 0; c < length; c++) {
    UPDATE_CRC(crc, buffer[c]);
  }
  return crc;
}

uint32_t calculateCRC(const byte* buffer, size_t length) {
  uint32_t crc = 0xFFFFFFFF;
  crc = updateCRC(buffer, length, crc);
  return ~crc;
}

uint32_t calculateCRC(FsFile& infile) {
  uint32_t byte_count;
  uint32_t crc = 0xFFFFFFFF;

  while ((byte_count = infile.read(sdBuffer, sizeof(sdBuffer))) != 0) {
    crc = updateCRC(sdBuffer, byte_count, crc);
  }
  return ~crc;
}

// Calculate rom's CRC32 from SD
uint32_t calculateCRC(char* fileName, char* folder, unsigned long offset) {
  FsFile infile;
  uint32_t result;

  sd.chdir(folder);
  if (infile.open(fileName, O_READ)) {
    infile.seek(offset);
    result = calculateCRC(infile);
    infile.close();
    return result;
  } else {
    display_Clear();
    print_Msg(F("File "));
    //print_Msg(folder);
    //print_Msg(F("/"));
    //print_Msg(fileName);
    print_FatalError(F(" not found"));
    return 0;
  }
}

/******************************************
   CRC Functions for Atari, Fairchild, Ody2, Arc, etc. modules
 *****************************************/
#if (defined(ENABLE_ODY2) || defined(ENABLE_ARC) || defined(ENABLE_FAIRCHILD) || defined(ENABLE_MSX) || defined(ENABLE_POKE) || defined(ENABLE_2600) || defined(ENABLE_5200) || defined(ENABLE_7800) || defined(ENABLE_C64) || defined(ENABLE_VECTREX) || defined(ENABLE_NES) || defined(ENABLE_LYNX) || defined(ENABLE_ATARI8) || defined(ENABLE_BALLY) || defined(ENABLE_LEAP) || defined(ENABLE_LJ) || defined(ENABLE_LJPRO) || defined(ENABLE_PV1000) || defined(ENABLE_PYUUTA) || defined(ENABLE_RCA) || defined(ENABLE_TI99) || defined(ENABLE_TRS80) || defined(ENABLE_VIC20) || defined(ENABLE_VSMILE))

void printCRC(char* checkFile, uint32_t* crcCopy, unsigned long offset) {
  uint32_t crc = calculateCRC(checkFile, folder, offset);
  char tempCRC[9];

  if (crcCopy != NULL) {
    *crcCopy = crc;
  }

  sprintf(tempCRC, "%08lX", crc);
  print_Msg(F("CRC: "));
  println_Msg(tempCRC);
  display_Update();
}
#endif

//******************************************
// Functions for CRC32 database
//******************************************
//Skip line
void skip_line(FsFile* readfile) {
  int i = 0;
  char str_buf;

  while (readfile->available()) {
    //Read 1 byte from file
    str_buf = readfile->read();

    //if end of file or newline found, execute command
    if (str_buf == '\r') {
      readfile->read();  //dispose \n because \r\n
      break;
    }
    i++;
  }  //End while
}

//Get line from file
void get_line(char* str_buf, FsFile* readfile, uint8_t maxi) {
  int read_len;

  // Status LED on
  statusLED(true);

  read_len = readfile->read(str_buf, maxi - 1);

  for (int i = 0; i < read_len; i++) {
    //if end of file or newline found, execute command
    if (str_buf[i] == '\r') {
      str_buf[i] = 0;
      readfile->seekCur(i - read_len + 2);  // +2 to skip over \n because \r\n
      return;
    }
  }
  str_buf[maxi - 1] = 0;
  // EOL was not found, keep looking (slower)
  while (readfile->available()) {
    if (readfile->read() == '\r') {
      readfile->read();  // read \n because \r\n
      break;
    }
  }
}

void rewind_line(FsFile& readfile, byte count = 1) {
  uint32_t position = readfile.curPosition();
  // To seek one line back, this code must step over the first newline it finds
  // in order to exit the current line and enter the end of the previous one.
  // Convert <count> from how-many-lines-back into how-many-newlines-to-look-for
  // by incrementing it by 1.
  count++;
  for (byte count_newline = 0; count_newline < count; count_newline++) {
    // Go to the strictly previous '\n', or file start.
    while (position) {
      // Seek back first (keeping position updated)...
      position--;
      readfile.seekCur(-1);
      // ...and check current byte second.
      // Note: this code assumed all files use ASCII with DOS-style newlines
      // so \n is encountered first when seeking backwards.
      if (readfile.peek() == '\n')
        break;
    }
  }
  // If not at file start, the current character is the '\n' just before the
  // desired line, so advance by one.
  if (position)
    readfile.seekCur(1);
}

// Calculate CRC32 if needed and compare it to CRC read from database
boolean compareCRC(const char* database, uint32_t crc32sum, boolean renamerom, int offset) {
  char crcStr[9];
  print_Msg(F("CRC32... "));
  display_Update();

  if (crc32sum == 0) {
    //go to root
    sd.chdir();
    // Calculate CRC32
    sprintf(crcStr, "%08lX", calculateCRC(fileName, folder, offset));
  } else {
    // Convert precalculated crc to string
    sprintf(crcStr, "%08lX", ~crc32sum);
  }
  // Print checksum
  print_Msg(crcStr);
  display_Update();

  //Search for CRC32 in file
  char gamename[96];
  char crc_search[9];

  //go to root
  sd.chdir();
  if (myFile.open(database, O_READ)) {
    //Search for same CRC in list
    while (myFile.available()) {
      //Read 2 lines (game name and CRC)
      get_line(gamename, &myFile, sizeof(gamename));
      get_line(crc_search, &myFile, sizeof(crc_search));
      skip_line(&myFile);  //Skip every 3rd line

      //if checksum search successful, rename the file and end search
      if (strcmp(crc_search, crcStr) == 0) {

#ifdef ENABLE_NES
        if ((mode == CORE_NES) && (offset != 0)) {
          // Rewind to iNES Header
          myFile.seekCur(-36);

          char iNES_STR[33];
          // Read iNES header
          get_line(iNES_STR, &myFile, 33);

          // Convert "4E4553" to (0x4E, 0x45, 0x53)
          unsigned int iNES_BUF;
          for (byte j = 0; j < 16; j++) {
            sscanf(iNES_STR + j * 2, "%2X", &iNES_BUF);
            iNES_HEADER[j] = iNES_BUF;
          }
          //Skip CRLF
          myFile.seekCur(4);
        }
#endif  // ENABLE_NES

        // Close the file:
        myFile.close();

        //Write iNES header
#ifdef ENABLE_NES
        if ((mode == CORE_NES) && (offset != 0)) {
          // Write iNES header
          sd.chdir(folder);
          if (!myFile.open(fileName, O_RDWR)) {
            print_FatalError(sd_error_STR);
          }
          for (byte z = 0; z < 16; z++) {
            myFile.write(iNES_HEADER[z]);
          }
          myFile.close();
        }
#endif  // ENABLE_NES
        print_Msg(F(" -> "));
        display_Update();

        if (renamerom) {
          println_Msg(gamename);

          // Rename file to database name
          sd.chdir(folder);
          delay(100);
          if (myFile.open(fileName, O_READ)) {
            myFile.rename(gamename);
            // Close the file:
            myFile.close();
          }
        } else {
          println_Msg(FS(FSTRING_OK));
        }
        return 1;
        break;
      }
    }
    if (strcmp(crc_search, crcStr) != 0) {
      print_Error(F(" -> Not found"));
      return 0;
    }
  } else {
    println_Msg(F(" -> Error"));
    print_Error(F("Database missing"));
    return 0;
  }
  return 0;
}

//******************************************
// Math Functions
//******************************************
#if (defined(ENABLE_NES) || defined(ENABLE_MSX) || defined(ENABLE_GBX) || defined(ENABLE_TRS80) || defined(ENABLE_JAGUAR))
int int_pow(int base, int exp) {  // Power for int
  int result = 1;
  while (exp) {
    if (exp & 1)
      result *= base;
    exp /= 2;
    base *= base;
  }
  return result;
}
#endif

void createFolder(const char* system, const char* subfolder, const char* gameName, const char* fileSuffix) {
  snprintf(fileName, FILENAME_LENGTH, "%s.%s", gameName, fileSuffix);

  // create a new folder for the rom file
  EEPROM_readAnything(0, foldern);
  if (subfolder == NULL) {
    sprintf(folder, "%s/%s/%d", system, gameName, foldern);
  } else {
    sprintf(folder, "%s/%s/%s/%d", system, subfolder, gameName, foldern);
  }
  sd.mkdir(folder, true);
  sd.chdir(folder);
}

void printAndIncrementFolder(bool displayClear = false) {
  // Save location
  if (displayClear) {
    display_Clear();
  }
  print_STR(saving_to_STR, 0);
  print_Msg(folder);
  println_Msg(F("/..."));
  display_Update();
  // write new folder number back to eeprom
  foldern = foldern + 1;
  EEPROM_writeAnything(0, foldern);
}

void createFolderAndOpenFile(const char* system, const char* subfolder, const char* gameName, const char* fileSuffix) {
  createFolder(system, subfolder, gameName, fileSuffix);
  printAndIncrementFolder(true);

  if (!myFile.open(fileName, O_RDWR | O_CREAT)) {
    print_FatalError(sd_error_STR);
  }
}

// move file pointer to first game line with matching letter. If no match is found the last database entry is selected
void seek_first_letter_in_database(FsFile& database, byte myLetter) {
  char gamename_str[3];
#ifdef ENABLE_GLOBAL_LOG
  // Disable log to prevent unnecessary logging
  println_Log(F("Select Mapping from List"));
  dont_log = true;
#endif
  database.rewind();
  // Skip ahead to selected starting letter
  if ((myLetter > 0) && (myLetter <= 26)) {
    myLetter += 'A' - 1;
    do {
      // Read current name
      get_line(gamename_str, &database, 2);
      // Skip data line
      skip_line(&database);
      // Skip empty line
      skip_line(&database);

    } while (database.available() && gamename_str[0] != myLetter);
    rewind_line(database, 3);
  }
#ifdef ENABLE_GLOBAL_LOG
  // Enable log again
  dont_log = false;
#endif
}

#if ( \
  defined(ENABLE_ARC) || defined(ENABLE_FAIRCHILD) || defined(ENABLE_VECTREX) || defined(ENABLE_BALLY) || defined(ENABLE_PV1000) || defined(ENABLE_PYUUTA) || defined(ENABLE_RCA) || defined(ENABLE_TRS80) || defined(ENABLE_LEAP) || defined(ENABLE_LJ) || defined(ENABLE_VSMILE))
// read single digit data line as byte
void readDataLineSingleDigit(FsFile& database, void* byteData) {
  // Read rom size
  (*(byte*)byteData) = database.read() - 48;

  // Skip rest of line
  database.seekCur(2);
}
#endif

#if ( \
   defined(ENABLE_ODY2) || defined(ENABLE_5200) || defined(ENABLE_7800) || defined(ENABLE_C64) || defined(ENABLE_JAGUAR) || \
   defined(ENABLE_VIC20)|| defined(ENABLE_ATARI8)\
 )
struct database_entry_mapper_size {
  byte gameMapper;
  byte gameSize;
};

// read database entry with mapper and size digits
void readDataLineMapperSize(FsFile& database, void* entry) {
  struct database_entry_mapper_size* castEntry = (database_entry_mapper_size*)entry;
  // Read mapper
  castEntry->gameMapper = database.read() - 48;

  // if next char is not a semicolon expect an additional digit
  char temp = database.read();
  if (temp != ',') {
    castEntry->gameMapper = (castEntry->gameMapper * 10) + (temp - 48);
    // Skip over semicolon
    database.seekCur(1);
  }

  // Read rom size
  castEntry->gameSize = database.read() - 48;

  // Skip rest of line
  database.seekCur(2);
}
#endif

// navigate through the database file using OSSC input buttons. Requires function pointer readData for reading device specific data line from database
// printDataLine - optional callback for printing device specific data informations about the currently browsed game
// setRomName - callback function to set rom name if game is selected
// returns true if a game was selected, false otherwise
boolean checkCartSelection(FsFile& database, void (*readData)(FsFile&, void*), void* data, void (*printDataLine)(void*) = NULL, void (*setRomName)(const char* input) = NULL) {
  char gamename[128];
  uint8_t fastScrolling = 1;

  // Display database
  while (database.available()) {
#ifdef ENABLE_GLOBAL_LOG
    // Disable log to prevent unnecessary logging
    dont_log = true;
#endif
    display_Clear();

    get_line(gamename, &database, sizeof(gamename));

    readData(database, data);

    skip_line(&database);

    println_Msg(F("Select your cartridge"));
    println_Msg(FS(FSTRING_EMPTY));
    println_Msg(gamename);

    if (printDataLine) {
      printDataLine(data);
    }
    println_Msg(FS(FSTRING_EMPTY));
#if defined(ENABLE_OLED)
    print_STR(press_to_change_STR, 0);
    if (fastScrolling > 1)
      println_Msg(F(" (fast)"));
    else
      println_Msg("");
    print_STR(right_to_select_STR, 1);
#elif defined(ENABLE_LCD)
    print_STR(rotate_to_change_STR, 0);
    if (fastScrolling > 1)
      println_Msg(F(" (fast)"));
    else
      println_Msg("");
    print_STR(press_to_select_STR, 1);
#elif defined(SERIAL_MONITOR)
    println_Msg(F("U/D to Change"));
    println_Msg(F("Space/Zero to Select"));
#endif
    display_Update();

#ifdef ENABLE_GLOBAL_LOG
    // Enable log again
    dont_log = false;
#endif
    uint8_t b = 0;
    while (1) {
      // Check button input
      b = checkButton();

      // Next
      if (b == 1) {
        // 1: Next record
        if (fastScrolling > 1) {
          for (uint8_t skipped = 0; skipped < fastScrolling * 3; skipped++) {
            skip_line(&database);
          }
        }
        break;
      }

      // Previous
      else if (b == 2) {
        // 2: Previous record
        if (fastScrolling > 1)
          rewind_line(database, fastScrolling * 3 + 3);
        else
          rewind_line(database, 6);
        break;
      }

      // Selection
      else if (b == 3) {
        if (setRomName) {
          setRomName(gamename);
        }
        database.close();
        return true;
      }

      else if (b == 4) {
        // 4: Toggle Fast Scrolling
        if (fastScrolling == 1)
          fastScrolling = 30;
        else
          fastScrolling = 1;
        continue;
      }
    }
  }
  return false;
}

#if ( \
  defined(ENABLE_ODY2) || defined(ENABLE_ARC) || defined(ENABLE_FAIRCHILD) || defined(ENABLE_MSX) || defined(ENABLE_POKE) || defined(ENABLE_2600) || defined(ENABLE_5200) || defined(ENABLE_7800) || defined(ENABLE_C64) || defined(ENABLE_VECTREX) || defined(ENABLE_NES) || defined(ENABLE_GBX) || defined(ENABLE_BALLY) || defined(ENABLE_PV1000) || defined(ENABLE_PYUUTA) || defined(ENABLE_RCA) || defined(ENABLE_TRS80) || defined(ENABLE_VIC20) || defined(ENABLE_LEAP) || defined(ENABLE_LJ) || defined(ENABLE_VSMILE) || defined(ENABLE_TI99) || defined(ENABLE_ATARI8))
void printInstructions() {
  println_Msg(FS(FSTRING_EMPTY));

#if defined(ENABLE_OLED)
  print_STR(press_to_change_STR, 1);
  print_STR(right_to_select_STR, 1);
#elif defined(ENABLE_LCD)
  print_STR(rotate_to_change_STR, 1);
  print_STR(press_to_select_STR, 1);
#elif defined(SERIAL_MONITOR)
  println_Msg(F("U/D to Change"));
  println_Msg(F("Space/Zero to Select"));
#endif /* ENABLE_OLED | ENABLE_LCD | SERIAL_MONITOR */

  display_Update();
}

#if (defined(ENABLE_OLED) || defined(ENABLE_LCD))
int navigateMenu(int min, int max, void (*printSelection)(int)) {
  uint8_t b = 0;
  int i = min;

  // Check Button Status
#if defined(ENABLE_OLED)
  buttonVal1 = (PIND & (1 << 7));  // PD7
#elif defined(ENABLE_LCD)
  boolean buttonVal1 = (PING & (1 << 2));  //PG2
#endif /* ENABLE_OLED | ENABLE_LCD */

  if (buttonVal1 == LOW) {  // Button Pressed
    while (1) {             // Scroll Mapper List
#if defined(ENABLE_OLED)
      buttonVal1 = (PIND & (1 << 7));  // PD7
#elif defined(ENABLE_LCD)
      buttonVal1 = (PING & (1 << 2));      // PG2
#endif /* ENABLE_OLED | ENABLE_LCD */

      if (buttonVal1 == HIGH) {  // Button Released
        // Correct Overshoot
        if (i == min)
          i = max;
        else
          i--;
        break;
      }
      printSelection(i);
      display_Update();
      if (i == max)
        i = min;
      else
        i++;
      delay(250);
    }
  }
  b = 0;

  printSelection(i);
  printInstructions();

  while (1) {
    b = checkButton();
    if (b == 2) {  // Previous Mapper (doubleclick)
      if (i == min)
        i = max;
      else
        i--;

      // Only update display after input because of slow LCD library
      printSelection(i);
      printInstructions();
    }
    if (b == 1) {  // Next Mapper (press)
      if (i == max)
        i = min;
      else
        i++;

      // Only update display after input because of slow LCD library
      printSelection(i);
      printInstructions();
    }
    if (b == 3) {  // Long Press - Execute (hold)
      return i;
    }
  }
}
#elif defined(SERIAL_MONITOR)
int navigateMenu(__attribute__((unused)) int min, __attribute__((unused)) int max, void (*printSelection)(int)) {
  printSelection(0);
  Serial.println(F("Enter number to change:_"));
  while (Serial.available() == 0) {}
  int selectedNumber = Serial.parseInt();
  delay(200);
  return selectedNumber;
}
#endif /* (ENABLE_OLED | ENABLE_LCD) */
#endif /* ENABLE_<CORES> */

#if (defined(ENABLE_OLED) || defined(ENABLE_LCD))
void starting_letter__subDraw(byte selection, byte line) {
  display.setDrawColor(0);
  for (uint8_t i = 0; i < 4; i++) display.drawLine(0, 10 + i * 16, 128, 10 + i * 16);
  display.setDrawColor(1);
  display.drawLine(4 + selection * 16, 10 + line * 16, 9 + selection * 16, 10 + line * 16);
  display_Update();
}
#endif /* (ENABLE_OLED | ENABLE_LCD) */

byte starting_letter() {
#ifdef ENABLE_GLOBAL_LOG
  // Disable log to prevent unnecessary logging
  dont_log = true;
#endif

#if (defined(ENABLE_LCD) || defined(ENABLE_OLED))
  byte selection = 0;
  byte line = 0;

  display_Clear();

  println_Msg(F("[#] [A] [B] [C] [D] [E] [F]"));
  println_Msg(FS(FSTRING_EMPTY));
  println_Msg(F("[G] [H] [ I ] [J] [K] [L] [M]"));
  println_Msg(FS(FSTRING_EMPTY));
  println_Msg(F("[N] [O] [P] [Q] [R] [S] [T]"));
  println_Msg(FS(FSTRING_EMPTY));
  println_Msg(F("[U] [V] [W] [X] [Y] [Z] [?]"));

  // Draw selection line
  display.setDrawColor(1);
  display.drawLine(4 + selection * 16, 10 + line * 16, 9 + selection * 16, 10 + line * 16);
  display_Update();

  while (1) {
    uint8_t b = checkButton();
    if (b == 2) {  // Previous
      if ((selection == 0) && (line > 0)) {
        line--;
        selection = 6;
      } else if ((selection == 0) && (line == 0)) {
        line = 3;
        selection = 6;
      } else if (selection > 0) {
        selection--;
      }
      starting_letter__subDraw(selection, line);
    } else if (b == 1) {  // Next
      if ((selection == 6) && (line < 3)) {
        line++;
        selection = 0;
      } else if ((selection == 6) && (line == 3)) {
        line = 0;
        selection = 0;
      } else if (selection < 6) {
        selection++;
      }
      starting_letter__subDraw(selection, line);
    } else if (b == 3) {  // Long Press - Execute
      if ((selection + line * 7) != 27) {
        display_Clear();
        println_Msg(F("Please wait..."));
        display_Update();
      }
      break;
    }
  }
  return (selection + line * 7);
#elif defined(SERIAL_MONITOR)
  Serial.println(F("Enter first letter: "));
  while (Serial.available() == 0) {
  }

  // Read the incoming byte:
  byte incomingByte = Serial.read();
  return incomingByte;
#endif

#ifdef ENABLE_GLOBAL_LOG
  // Enable log again
  dont_log = false;
#endif
}

void print_MissingModule(void) {
  display_Clear();
  println_Msg(F("Please enable module"));
  print_FatalError(F("in Config.h."));
}

/******************************************
  Main menu
*****************************************/
constexpr char modeItem1[] PROGMEM = "Game Boy";
constexpr char modeItem2[] PROGMEM = "NES/Famicom";
constexpr char modeItem3[] PROGMEM = "Super Nintendo/SFC";
constexpr char modeItem4[] PROGMEM = "Nintendo 64 (3V)";
constexpr char modeItem5[] PROGMEM = "Mega Drive/Genesis";
constexpr char modeItem6[] PROGMEM = "SMS/GG/MIII/SG-1000";
constexpr char modeItem7[] PROGMEM = "PC Engine/TG16";
constexpr char modeItem8[] PROGMEM = "WonderSwan (3V)";
constexpr char modeItem9[] PROGMEM = "NeoGeo Pocket (3V)";
constexpr char modeItem10[] PROGMEM = "Intellivision";
constexpr char modeItem11[] PROGMEM = "Colecovision";
constexpr char modeItem12[] PROGMEM = "Virtual Boy";
constexpr char modeItem13[] PROGMEM = "Watara Supervision (3V)";
constexpr char modeItem14[] PROGMEM = "Pocket Challenge W";
constexpr char modeItem15[] PROGMEM = "Atari 2600";
constexpr char modeItem16[] PROGMEM = "Magnavox Odyssey 2";
constexpr char modeItem17[] PROGMEM = "Arcadia 2001";
constexpr char modeItem18[] PROGMEM = "Fairchild Channel F";
constexpr char modeItem19[] PROGMEM = "Super A'can";
constexpr char modeItem20[] PROGMEM = "MSX";
constexpr char modeItem21[] PROGMEM = "Pokemon Mini (3V)";
constexpr char modeItem22[] PROGMEM = "Casio Loopy";
constexpr char modeItem23[] PROGMEM = "Commodore 64";
constexpr char modeItem24[] PROGMEM = "Atari 5200";
constexpr char modeItem25[] PROGMEM = "Atari 7800";
constexpr char modeItem26[] PROGMEM = "Atari Jaguar";
constexpr char modeItem27[] PROGMEM = "Atari Lynx";
constexpr char modeItem28[] PROGMEM = "Vectrex";
constexpr char modeItem29[] PROGMEM = "Atari 8-bit";
constexpr char modeItem30[] PROGMEM = "Bally Astrocade";
constexpr char modeItem31[] PROGMEM = "Bandai LJ";
constexpr char modeItem32[] PROGMEM = "Bandai LJ Pro";
constexpr char modeItem33[] PROGMEM = "Casio PV-1000";
constexpr char modeItem34[] PROGMEM = "Commodore VIC-20";
constexpr char modeItem35[] PROGMEM = "LF Leapster (3V)";
constexpr char modeItem36[] PROGMEM = "RCA Studio II";
constexpr char modeItem37[] PROGMEM = "TI-99";
constexpr char modeItem38[] PROGMEM = "Tomy Pyuuta";
constexpr char modeItem39[] PROGMEM = "TRS-80";
constexpr char modeItem40[] PROGMEM = "Vtech V.Smile (3V)";
constexpr char modeItem41[] PROGMEM = "Flashrom Programmer";
constexpr char modeItem42[] PROGMEM = "Self Test (3V)";
constexpr char modeItem43[] PROGMEM = "About";

static const char* const modeOptions[] PROGMEM = {
#ifdef ENABLE_GBX
  modeItem1,
#endif
#ifdef ENABLE_NES
  modeItem2,
#endif
#ifdef ENABLE_SNES
  modeItem3,
#endif
#ifdef ENABLE_N64
  modeItem4,
#endif
#ifdef ENABLE_MD
  modeItem5,
#endif
#ifdef ENABLE_SMS
  modeItem6,
#endif
#ifdef ENABLE_PCE
  modeItem7,
#endif
#ifdef ENABLE_WS
  modeItem8,
#endif
#ifdef ENABLE_NGP
  modeItem9,
#endif
#ifdef ENABLE_INTV
  modeItem10,
#endif
#ifdef ENABLE_COLV
  modeItem11,
#endif
#ifdef ENABLE_VBOY
  modeItem12,
#endif
#ifdef ENABLE_WSV
  modeItem13,
#endif
#ifdef ENABLE_PCW
  modeItem14,
#endif
#ifdef ENABLE_2600
  modeItem15,
#endif
#ifdef ENABLE_ODY2
  modeItem16,
#endif
#ifdef ENABLE_ARC
  modeItem17,
#endif
#ifdef ENABLE_FAIRCHILD
  modeItem18,
#endif
#ifdef ENABLE_SUPRACAN
  modeItem19,
#endif
#ifdef ENABLE_MSX
  modeItem20,
#endif
#ifdef ENABLE_POKE
  modeItem21,
#endif
#ifdef ENABLE_LOOPY
  modeItem22,
#endif
#ifdef ENABLE_C64
  modeItem23,
#endif
#ifdef ENABLE_5200
  modeItem24,
#endif
#ifdef ENABLE_7800
  modeItem25,
#endif
#ifdef ENABLE_JAGUAR
  modeItem26,
#endif
#ifdef ENABLE_LYNX
  modeItem27,
#endif
#ifdef ENABLE_VECTREX
  modeItem28,
#endif
#ifdef ENABLE_ATARI8
  modeItem29,
#endif
#ifdef ENABLE_BALLY
  modeItem30,
#endif
#ifdef ENABLE_LJ
  modeItem31,
#endif
#ifdef ENABLE_LJPRO
  modeItem32,
#endif
#ifdef ENABLE_PV1000
  modeItem33,
#endif
#ifdef ENABLE_VIC20
  modeItem34,
#endif
#ifdef ENABLE_LEAP
  modeItem35,
#endif
#ifdef ENABLE_RCA
  modeItem36,
#endif
#ifdef ENABLE_TI99
  modeItem37,
#endif
#ifdef ENABLE_PYUUTA
  modeItem38,
#endif
#ifdef ENABLE_TRS80
  modeItem39,
#endif
#ifdef ENABLE_VSMILE
  modeItem40,
#endif
#ifdef ENABLE_FLASH
  modeItem41,
#endif
#ifdef ENABLE_SELFTEST
  modeItem42,
#endif
  modeItem43, FSTRING_RESET

};

uint8_t pageMenu(const __FlashStringHelper* question, const char* const* menuStrings, uint8_t entryCount, uint8_t default_choice = 0) {
  // Create menu
  uint8_t modeMenu;
  uint8_t num_answers;
  uint8_t option_offset;

  // Menu spans across multiple pages
  currPage = 1;
  lastPage = 1;

  numPages = (entryCount / 7) + ((entryCount % 7) != 0);

  do {
    option_offset = (currPage - 1) * 7;
    num_answers = ((entryCount < (option_offset + 7)) ? entryCount - option_offset : 7);

    // Copy menuOptions out of progmem
    convertPgm(menuStrings + option_offset, num_answers);
    modeMenu = question_box(question, menuOptions, num_answers, default_choice) + option_offset;
  } while (numPages != 0);

  // Reset page number
  currPage = 1;

  return modeMenu;
}

// All included slots
void mainMenu() {
  // wait for user choice to come back from the question box menu
  switch (pageMenu(F("OPEN SOURCE CART READER"), modeOptions, SYSTEM_MENU_TOTAL)) {

#ifdef ENABLE_GBX
    case SYSTEM_MENU_GBX:
      return gbxMenu();
#endif

#ifdef ENABLE_NES
    case SYSTEM_MENU_NES:
      mode = CORE_NES;
      display_Clear();
      display_Update();
      setup_NES();
      getMapping();
      checkStatus_NES();
      return nesMenu();
#endif

#ifdef ENABLE_SNES
    case SYSTEM_MENU_SNES:
      return snsMenu();
#endif

#ifdef ENABLE_N64
    case SYSTEM_MENU_N64:
      return n64Menu();
#endif

#ifdef ENABLE_MD
    case SYSTEM_MENU_MD:
      return mdMenu();
#endif

#ifdef ENABLE_SMS
    case SYSTEM_MENU_SMS:
      return smsMenu();
#endif

#ifdef ENABLE_PCE
    case SYSTEM_MENU_PCE:
      return pcsMenu();
#endif

#ifdef ENABLE_WS
    case SYSTEM_MENU_WS:
      display_Clear();
      display_Update();
      setup_WS();
      mode = CORE_WS;
      return wsMenu();
#endif

#ifdef ENABLE_NGP
    case SYSTEM_MENU_NGP:
      display_Clear();
      display_Update();
      setup_NGP();
      mode = CORE_NGP;
      break;
#endif

#ifdef ENABLE_INTV
    case SYSTEM_MENU_INTV:
      setup_INTV();
      return intvMenu();
#endif

#ifdef ENABLE_COLV
    case SYSTEM_MENU_COLV:
      setup_COL();
      return colMenu();
      break;
#endif

#ifdef ENABLE_VBOY
    case SYSTEM_MENU_VBOY:
      setup_VBOY();
      vboyMenu();
      break;
#endif

#ifdef ENABLE_WSV
    case SYSTEM_MENU_WSV:
      setup_WSV();
      return wsvMenu();
      break;
#endif

#ifdef ENABLE_PCW
    case SYSTEM_MENU_PCW:
      setup_PCW();
      return pcwMenu();
      break;
#endif

#ifdef ENABLE_2600
    case SYSTEM_MENU_2600:
      setup_2600();
      return a2600Menu();
      break;
#endif

#ifdef ENABLE_ODY2
    case SYSTEM_MENU_ODY2:
      setup_ODY2();
      return ody2Menu();
      break;
#endif

#ifdef ENABLE_ARC
    case SYSTEM_MENU_ARC:
      setup_ARC();
      return arcMenu();
      break;
#endif

#ifdef ENABLE_FAIRCHILD
    case SYSTEM_MENU_FAIRCHILD:
      setup_FAIRCHILD();
      return fairchildMenu();
      break;
#endif

#ifdef ENABLE_SUPRACAN
    case SYSTEM_MENU_SUPRACAN:
      return setup_SuprAcan();
      break;
#endif

#ifdef ENABLE_MSX
    case SYSTEM_MENU_MSX:
      setup_MSX();
      return msxMenu();
      break;
#endif

#ifdef ENABLE_POKE
    case SYSTEM_MENU_POKE:
      setup_POKE();
      return pokeMenu();
      break;
#endif

#ifdef ENABLE_LOOPY
    case SYSTEM_MENU_LOOPY:
      setup_LOOPY();
      return loopyMenu();
      break;
#endif

#ifdef ENABLE_C64
    case SYSTEM_MENU_C64:
      setup_C64();
      return c64Menu();
      break;
#endif

#ifdef ENABLE_5200
    case SYSTEM_MENU_5200:
      setup_5200();
      return a5200Menu();
      break;
#endif

#ifdef ENABLE_7800
    case SYSTEM_MENU_7800:
      setup_7800();
      return a7800Menu();
      break;
#endif
#ifdef ENABLE_JAGUAR
    case SYSTEM_MENU_JAGUAR:
      setup_Jag();
      return jagMenu();
      break;
#endif

#ifdef ENABLE_LYNX
    case SYSTEM_MENU_LYNX:
      setup_LYNX();
      return lynxMenu();
      break;
#endif

#ifdef ENABLE_VECTREX
    case SYSTEM_MENU_VECTREX:
      setup_VECTREX();
      return vectrexMenu();
      break;
#endif

#ifdef ENABLE_ATARI8
    case SYSTEM_MENU_ATARI8:
      setup_ATARI8();
      return atari8Menu();
      break;
#endif

#ifdef ENABLE_BALLY
    case SYSTEM_MENU_BALLY:
      setup_BALLY();
      return ballyMenu();
      break;
#endif

#ifdef ENABLE_LJ
    case SYSTEM_MENU_LJ:
      setup_LJ();
      return ljMenu();
      break;
#endif

#ifdef ENABLE_LJPRO
    case SYSTEM_MENU_LJPRO:
      setup_LJPRO();
      return ljproMenu();
      break;
#endif

#ifdef ENABLE_PV1000
    case SYSTEM_MENU_PV1000:
      setup_PV1000();
      return pv1000Menu();
      break;
#endif

#ifdef ENABLE_VIC20
    case SYSTEM_MENU_VIC20:
      setup_VIC20();
      return vic20Menu();
      break;
#endif

#ifdef ENABLE_LEAP
    case SYSTEM_MENU_LEAP:
      setup_LEAP();
      return leapMenu();
      break;
#endif

#ifdef ENABLE_RCA
    case SYSTEM_MENU_RCA:
      setup_RCA();
      return rcaMenu();
      break;
#endif

#ifdef ENABLE_TI99
    case SYSTEM_MENU_TI99:
      setup_TI99();
      return ti99Menu();
      break;
#endif

#ifdef ENABLE_PYUUTA
    case SYSTEM_MENU_PYUUTA:
      setup_PYUUTA();
      return pyuutaMenu();
      break;
#endif

#ifdef ENABLE_TRS80
    case SYSTEM_MENU_TRS80:
      setup_TRS80();
      return trs80Menu();
      break;
#endif

#ifdef ENABLE_VSMILE
    case SYSTEM_MENU_VSMILE:
      setup_VSMILE();
      return vsmileMenu();
      break;
#endif

#ifdef ENABLE_FLASH
    case SYSTEM_MENU_FLASH:
#ifdef ENABLE_VSELECT
      setup_FlashVoltage();
#endif
      return flashMenu();
      break;
#endif

#ifdef ENABLE_SELFTEST
    case SYSTEM_MENU_SELFTEST:
      return selfTest();
      break;
#endif

    case SYSTEM_MENU_ABOUT:
      return aboutScreen();
      break;

    case SYSTEM_MENU_RESET:
      return resetArduino();
      break;

    default:
      return print_MissingModule();  // does not return
  }
}


/******************************************
  Self Test
*****************************************/
#ifdef ENABLE_SELFTEST
// Check if given pin number is one of pins 2-9, 14-17, 22-37, 42-49, 54-69
bool isPin_2t9_14t17_22t37_42t49_54t69(byte pinNumber) {
  return ((2 <= pinNumber) && (pinNumber <= 9)) || ((14 <= pinNumber) && (pinNumber <= 17)) || ((22 <= pinNumber) && (pinNumber <= 37)) || ((42 <= pinNumber) && (pinNumber <= 49)) || ((54 <= pinNumber) && (pinNumber <= 69));
}

void selfTest() {
#ifdef ENABLE_VSELECT
  // Set Automatic Voltage Selection to 3V
  setVoltage(VOLTS_SET_3V3);
#endif

  display_Clear();
  println_Msg(F("Self Test"));
  println_Msg(FS(FSTRING_EMPTY));
  println_Msg(F("Remove all Cartridges"));
  println_Msg(F("before continuing!"));
#if (defined(HW3) || defined(HW2))
  println_Msg(F("And turn the EEP switch on."));
#else
  println_Msg(FS(FSTRING_EMPTY));
#endif
  println_Msg(FS(FSTRING_EMPTY));
  println_Msg(FS(FSTRING_EMPTY));
  print_STR(press_button_STR, 1);
  display_Update();
  wait();
  display_Clear();

  // Test if pin 7 is held high by 1K resistor
  pinMode(7, INPUT);
  println_Msg(F("Testing 1K resistor "));
  display_Update();

  if (!digitalRead(7)) {
    rgbLed(red_color);
    errorLvl = 1;
    println_Msg(F("Error"));
    println_Msg(FS(FSTRING_EMPTY));
    print_STR(press_button_STR, 1);
    display_Update();
    wait();
    resetArduino();
  }

  println_Msg(F("Testing short to GND"));
  display_Update();

  // Set pins 2-9, 14-17, 22-37, 42-49, 54-69 to input and activate internal pull-up resistors
  for (byte pinNumber = 2; pinNumber <= 69; pinNumber++) {
    if (isPin_2t9_14t17_22t37_42t49_54t69(pinNumber)) {
      pinMode(pinNumber, INPUT_PULLUP);
    }
  }

  // Tests pins 2-9, 14-17, 22-37, 42-49, 54-69 for short to GND
  for (byte pinNumber = 2; pinNumber <= 69; pinNumber++) {
    if (isPin_2t9_14t17_22t37_42t49_54t69(pinNumber)) {
      if (!digitalRead(pinNumber)) {
        rgbLed(red_color);
        errorLvl = 1;
        print_Msg(F("Error: Pin "));
        if ((54 <= pinNumber) && (pinNumber <= 69)) {
          print_Msg(F("A"));
          println_Msg(pinNumber - 54);
        } else {
          print_Msg(F("D"));
          println_Msg(pinNumber);
        }
        println_Msg(FS(FSTRING_EMPTY));
        print_STR(press_button_STR, 1);
        display_Update();
        wait();
        resetArduino();
      }
    }
  }

  println_Msg(F("Testing short between pins"));
  display_Update();

  // Test for short between pins 2-9, 14-17, 22-37, 42-49, 54-69
  for (byte pinNumber = 2; pinNumber <= 69; pinNumber++) {
    if (isPin_2t9_14t17_22t37_42t49_54t69(pinNumber)) {
      pinMode(pinNumber, OUTPUT);
      digitalWrite(pinNumber, LOW);
      for (byte pinNumber2 = 2; pinNumber2 <= 69; pinNumber2++) {
        if (isPin_2t9_14t17_22t37_42t49_54t69(pinNumber2) && (pinNumber != pinNumber2)) {
          pinMode(pinNumber2, INPUT_PULLUP);
          if (!digitalRead(pinNumber2)) {
            rgbLed(red_color);
            errorLvl = 1;
            print_Msg(F("Error: Pin "));
            if ((54 <= pinNumber) && (pinNumber <= 69)) {
              print_Msg(F("A"));
              print_Msg(pinNumber - 54);
            } else {
              print_Msg(F("D"));
              print_Msg(pinNumber);
            }
            print_Msg(F(" + "));
            if ((54 <= pinNumber2) && (pinNumber2 <= 69)) {
              print_Msg(F("A"));
              println_Msg(pinNumber2 - 54);
            } else {
              print_Msg(F("D"));
              println_Msg(pinNumber2);
            }
            println_Msg(FS(FSTRING_EMPTY));
            print_STR(press_button_STR, 1);
            display_Update();
            wait();
            resetArduino();
          }
        }
      }
      pinMode(pinNumber, INPUT_PULLUP);
    }
  }

  println_Msg(F("Testing Clock Generator"));
  initializeClockOffset();
  if (!i2c_found) {
    rgbLed(red_color);
    errorLvl = 1;
    println_Msg(F("Error: Clock Generator"));
    println_Msg(F("not found"));
    println_Msg(FS(FSTRING_EMPTY));
    print_STR(press_button_STR, 1);
    display_Update();
    wait();
    resetArduino();
  } else {
    //clockgen.set_correction(cal_factor, SI5351_PLL_INPUT_XO);
    clockgen.set_pll(SI5351_PLL_FIXED, SI5351_PLLA);
    clockgen.set_pll(SI5351_PLL_FIXED, SI5351_PLLB);
    //clockgen.pll_reset(SI5351_PLLA);
    //clockgen.pll_reset(SI5351_PLLB);
    clockgen.set_freq(400000000ULL, SI5351_CLK0);
    clockgen.set_freq(100000000ULL, SI5351_CLK1);
    clockgen.set_freq(307200000ULL, SI5351_CLK2);
    clockgen.output_enable(SI5351_CLK1, 1);
    clockgen.output_enable(SI5351_CLK2, 1);
    clockgen.output_enable(SI5351_CLK0, 1);
  }

  println_Msg(FS(FSTRING_EMPTY));
  println_Msg(F("All tests passed."));
  println_Msg(FS(FSTRING_EMPTY));
  print_STR(press_button_STR, 1);
  display_Update();
  wait();
  resetArduino();
}
#endif

/******************************************
  About Screen
*****************************************/
// Info Screen
void aboutScreen() {
  display_Clear();
  println_Msg(F("Cartridge Reader"));
  println_Msg(F("github.com/sanni"));
  print_Msg(F("2024 FW "));
  println_Msg(FS(FSTRING_VERSION));
  println_Msg(FS(FSTRING_EMPTY));
  println_Msg(FS(FSTRING_EMPTY));
  println_Msg(FS(FSTRING_EMPTY));
  println_Msg(FS(FSTRING_EMPTY));
  // Prints string out of the common strings array either with or without newline
  print_STR(press_button_STR, 1);
  display_Update();

  while (1) {

#if (defined(ENABLE_LCD) || defined(ENABLE_OLED))
    // get input button
    uint8_t b = checkButton();

    // if the cart readers input button is pressed shortly
    if (b == 1) {
      resetArduino();
    }

    // if the cart readers input button is pressed long
    if (b == 3) {
      resetArduino();
    }

    // if the button is pressed super long
    if (b == 4) {
      display_Clear();
      println_Msg(F("Resetting folder..."));
      display_Update();
      delay(2000);
      foldern = 0;
      EEPROM_writeAnything(0, foldern);
      resetArduino();
    }
#elif defined(ENABLE_SERIAL)
    wait_serial();
    resetArduino();
#endif
  }
}

/******************************************
  Progressbar
*****************************************/
void draw_progressbar(uint32_t processed, uint32_t total) {
  uint8_t current, i;
  static uint8_t previous;
  uint8_t steps = 20;

  //Find progressbar length and draw if processed size is not 0
  if (processed == 0) {
    previous = 0;
    print_Msg(F("["));
    display_Update();
    return;
  }

  // Progress bar
  current = (processed >= total) ? steps : processed / (total / steps);

  //Draw "*" if needed
  if (current > previous) {
    for (i = previous; i < current; i++) {
      // steps are 20, so 20 - 1 = 19.
      if (i == (19)) {
        //If end of progress bar, finish progress bar by drawing "]"
        println_Msg(F("]"));
      } else {
        print_Msg(F("*"));
      }
    }
    //update previous "*" status
    previous = current;
    //Update display
    display_Update();
  }
}

/******************************************
  RTC Module
*****************************************/
#ifdef ENABLE_RTC
#if defined(DS3231)
RTC_DS3231 rtc;
#elif defined(DS1307)
RTC_DS1307 rtc;
#endif

// Start Time
void RTCStart() {
  // Start RTC
  if (!rtc.begin()) {
    abort();
  }

  // RTC_DS1307 does not have lostPower()
#if defined(DS3231)
  // Set RTC Date/Time of Sketch Build if it lost battery power
  // After initial setup it would have lost battery power ;)
  if (rtc.lostPower()) {
    rtc.adjust(DateTime(F(__DATE__), F(__TIME__)));
  }
#endif
}

// Set Date/Time Callback Funtion
// Callback for file timestamps
void dateTime(uint16_t* date, uint16_t* time) {
  DateTime now = rtc.now();

  // Return date using FAT_DATE macro to format fields
  *date = FAT_DATE(now.year(), now.month(), now.day());

  // Return time using FAT_TIME macro to format fields
  *time = FAT_TIME(now.hour(), now.minute(), now.second());
}


/******************************************
  RTC Time Stamp Setup
  Call in any other script
*****************************************/
// Format a Date/Time stamp
String RTCStamp() {
  // Set a format
  char dtstamp[] = "DDMMMYYYY hh:mm:ssAP";

  // Get current Date/Time
  DateTime now = rtc.now();

  // Convert it to a string and caps lock it
  String dts = now.toString(dtstamp);
  dts.toUpperCase();

  // Print results
  return dts;
}
#endif

/******************************************
   Clockgen Calibration
 *****************************************/
#ifdef OPTION_CLOCKGEN_CALIBRATION
int32_t cal_factor = 0;
int32_t old_cal = 0;
int32_t cal_offset = 100;

void clkcal() {
  // Adafruit Clock Generator
  // last number is the clock correction factor which is custom for each clock generator
  cal_factor = readClockOffset();

  display_Clear();
  print_Msg(F("Read correction: "));
  println_Msg(String(cal_factor));
  display_Update();
  delay(500);

  if (cal_factor > INT32_MIN) {
    i2c_found = clockgen.init(SI5351_CRYSTAL_LOAD_8PF, 0, cal_factor);
  } else {
    i2c_found = clockgen.init(SI5351_CRYSTAL_LOAD_8PF, 0, 0);
    cal_factor = 0;
  }

  if (!i2c_found) {
    display_Clear();
    print_FatalError(F("Clock Generator not found"));
  }

  //clockgen.set_correction(cal_factor, SI5351_PLL_INPUT_XO);
  clockgen.set_pll(SI5351_PLL_FIXED, SI5351_PLLA);
  clockgen.set_pll(SI5351_PLL_FIXED, SI5351_PLLB);
  //clockgen.pll_reset(SI5351_PLLA);
  //clockgen.pll_reset(SI5351_PLLB);
  clockgen.set_freq(400000000ULL, SI5351_CLK0);
  clockgen.set_freq(100000000ULL, SI5351_CLK1);
  clockgen.set_freq(307200000ULL, SI5351_CLK2);
  clockgen.output_enable(SI5351_CLK1, 1);
  clockgen.output_enable(SI5351_CLK2, 1);
  clockgen.output_enable(SI5351_CLK0, 1);

  // Frequency Counter
  delay(500);
  FreqCount.begin(1000);
  while (1) {
    if (old_cal != cal_factor) {
      display_Clear();
      println_Msg(F("Adjusting..."));
      display_Update();
      clockgen.set_correction(cal_factor, SI5351_PLL_INPUT_XO);
      clockgen.set_pll(SI5351_PLL_FIXED, SI5351_PLLA);
      clockgen.set_pll(SI5351_PLL_FIXED, SI5351_PLLB);
      clockgen.pll_reset(SI5351_PLLA);
      clockgen.pll_reset(SI5351_PLLB);
      clockgen.set_freq(400000000ULL, SI5351_CLK0);
      clockgen.set_freq(100000000ULL, SI5351_CLK1);
      clockgen.set_freq(307200000ULL, SI5351_CLK2);
      old_cal = cal_factor;
      delay(500);
    } else {
      clockgen.update_status();
      while (clockgen.dev_status.SYS_INIT == 1) {
      }

      if (FreqCount.available()) {
        float count = FreqCount.read();
        display_Clear();
        println_Msg(F("Clock Calibration"));
        print_Msg(F("Freq:   "));
        print_Msg(count);
        println_Msg(F("Hz"));
        print_Msg(F("Correction:"));
        println_Msg(String(cal_factor));
        print_Msg(F("Step:"));
        print_right(cal_offset);
        println_Msg(FS(FSTRING_EMPTY));
#ifdef ENABLE_BUTTON2
        println_Msg(F("(Hold button to save)"));
        println_Msg(FS(FSTRING_EMPTY));
        println_Msg(F("Decrease     Increase"));
#else
#ifdef ENABLE_ROTARY
        println_Msg(F("Rotate to adjust Frequency"));
        println_Msg(F("Press to change step width"));
        println_Msg(F("Hold to save"));
#else
        println_Msg(F("Click/dbl to adjust"));
#endif
#endif
        display_Update();
      }
#ifdef ENABLE_BUTTON2
      // get input button
      uint8_t a = checkButton1();
      uint8_t b = checkButton2();

      // if the cart readers input button is pressed shortly
      if (a == 1) {
        old_cal = cal_factor;
        cal_factor -= cal_offset;
      }
      if (b == 1) {
        old_cal = cal_factor;
        cal_factor += cal_offset;
      }

      // if the cart readers input buttons is double clicked
      if (a == 2) {
        cal_offset /= 10ULL;
        if (cal_offset < 1) {
          cal_offset = 100000000ULL;
        }
      }
      if (b == 2) {
        cal_offset *= 10ULL;
        if (cal_offset > 100000000ULL) {
          cal_offset = 1;
        }
      }

      // if the cart readers input button is pressed long
      if (a == 3) {
        savetofile();
      }
      if (b == 3) {
        savetofile();
      }
#else
      //Handle inputs for either rotary encoder or single button interface.
      uint8_t a = checkButton();

      if (a == 1) {  //clockwise rotation or single click
        old_cal = cal_factor;
        cal_factor += cal_offset;
      }

      if (a == 2) {  //counterclockwise rotation or double click
        old_cal = cal_factor;
        cal_factor -= cal_offset;
      }

      if (a == 3) {  //button short hold
        cal_offset *= 10ULL;
        if (cal_offset > 100000000ULL) {
          cal_offset = 1;
        }
      }

      if (a == 4) {  //button long hold
        savetofile();
      }
#endif
    }
  }
}

void print_right(int32_t number) {
  int32_t abs_number = number;
  if (abs_number < 0)
    abs_number *= -1;
  else
    print_Msg(FS(FSTRING_SPACE));

  if (abs_number == 0)
    abs_number = 1;
  while (abs_number < 100000000ULL) {
    print_Msg(FS(FSTRING_SPACE));
    abs_number *= 10ULL;
  }
  println_Msg(number);
}

void savetofile() {
  display_Clear();
  println_Msg(F("Saving..."));
  println_Msg(String(cal_factor));
  display_Update();
  delay(2000);

  if (!myFile.open("/snes_clk.txt", O_WRITE | O_CREAT | O_TRUNC)) {
    print_FatalError(sd_error_STR);
  }
  // Write calibration factor to file
  myFile.print(cal_factor);

  // Close the file:
  myFile.close();
  print_STR(done_STR, 1);
  display_Update();
  delay(1000);
  resetArduino();
}
#endif

#if defined(OPTION_CLOCKGEN_CALIBRATION) || defined(OPTION_CLOCKGEN_USE_CALIBRATION)
int32_t atoi32_signed(const char* input_string) {
  if (input_string == NULL) {
    return 0;
  }

  int int_sign = 1;
  int i = 0;

  if (input_string[0] == '-') {
    int_sign = -1;
    i = 1;
  }

  int32_t return_val = 0;

  while (input_string[i] != '\0') {
    if (input_string[i] >= '0' && input_string[i] <= '9') {
      return_val = (return_val * 10) + (input_string[i] - '0');
    } else if (input_string[i] != '\0') {
      return 0;
    }

    i++;
  }

  return_val = return_val * int_sign;

  return return_val;
}

int32_t readClockOffset() {
  FsFile clock_file;
  char* clock_buf;
  int16_t i;
  int32_t clock_offset;

  if (!clock_file.open("/snes_clk.txt", O_READ)) {
    return INT32_MIN;
  }

  clock_buf = (char*)malloc(12 * sizeof(char));
  i = clock_file.read(clock_buf, 11);
  clock_file.close();
  if (i == -1) {
    free(clock_buf);
    return INT32_MIN;
  } else if ((i == 11) && (clock_buf[0] != '-')) {
    free(clock_buf);
    return INT32_MIN;
  } else {
    clock_buf[i] = 0;
  }

  for (i = 0; i < 12; i++) {
    if (clock_buf[i] != '-' && clock_buf[i] < '0' && clock_buf[i] > '9') {
      if (i == 0) {
        free(clock_buf);
        return INT32_MIN;
      } else if ((i == 1) && (clock_buf[0] == '-')) {
        free(clock_buf);
        return INT32_MIN;
      } else {
        clock_buf[i] = 0;
      }
    }
  }

  clock_offset = atoi32_signed(clock_buf);
  free(clock_buf);

  return clock_offset;
}
#endif

int32_t initializeClockOffset() {
#ifdef OPTION_CLOCKGEN_USE_CALIBRATION
  FsFile clock_file;
  const char zero_char_arr[] = { '0' };
  int32_t clock_offset = readClockOffset();
  if (clock_offset > INT32_MIN) {
    i2c_found = clockgen.init(SI5351_CRYSTAL_LOAD_8PF, 0, clock_offset);
  } else {
    i2c_found = clockgen.init(SI5351_CRYSTAL_LOAD_8PF, 0, 0);
    if (clock_file.open("/snes_clk.txt", O_WRITE | O_CREAT | O_TRUNC)) {
      clock_file.write(zero_char_arr, 1);
      clock_file.close();
    }
  }
  return clock_offset;
#else
  // last number is the clock correction factor which is custom for each clock generator
  i2c_found = clockgen.init(SI5351_CRYSTAL_LOAD_8PF, 0, 0);
  return 0;
#endif
}

/******************************************
   Setup
 *****************************************/
void setup() {
  // Set Button Pin PG2 to Input
  DDRG &= ~(1 << 2);
#if defined(HW5) && !defined(ENABLE_VSELECT)
  /**
   * HW5 has status LED connected to PD7
   * Set LED Pin PD7 to Output
   **/
  DDRD |= (1 << 7);
  PORTD |= (1 << 7);
#elif defined(ENABLE_VSELECT)
  /**
   * VSELECT uses pin PD7
   * Set LED Pin PD7 to Output
   **/
  DDRD |= (1 << 7);
#else  /* !defined(HW5) && !defined(ENABLE_VSELECT) */
  /**
   * HW1-3 have button connected to PD7
   * Set pin PD7 to input for button
   **/
  DDRD &= ~(1 << 7);
#endif /* HW5 &| ENABLE_VSELECT */

  // Set power to low to protect carts
  setVoltage(VOLTS_SET_3V3);

#if defined(ENABLE_3V3FIX)
  // Set clock high during setup
  setClockScale(CLKSCALE_16MHZ);
  delay(10);
#endif /* ENABLE_3V3FIX */

#if !defined(ENABLE_SERIAL) && defined(ENABLE_UPDATER)
  ClockedSerial.begin(UPD_BAUD);
  printVersionToSerial();
  ClockedSerial.flush();
#endif /* ENABLE_UPDATER */

  // Read current folder number out of the EEPROM
  EEPROM_readAnything(0, foldern);
  if (foldern < 0) foldern = 0;

#ifdef ENABLE_LCD
  display.begin();
  display.setContrast(40);
  display.setFont(u8g2_font_haxrcorp4089_tr);
#endif /* ENABLE_LCD */

#ifdef ENABLE_NEOPIXEL
  pixels.begin();
  setColor_RGB(0, 0, 100);

  // Set TX0 LED Pin(PE1) to Output for status indication during flashing for HW4
#if !(defined(ENABLE_SERIAL) || defined(HW5))
  DDRE |= (1 << 1);
#endif /* ENABLE_SERIAL */
#else  /* !ENABLE_NEOPIXEL */
#ifndef ENABLE_LCD
#ifdef ENABLE_CA_LED
  // Turn LED off
  digitalWrite(12, 1);
  digitalWrite(11, 1);
  digitalWrite(10, 1);
#endif /* ENABLE_CA_LED */
  // Configure 4 Pin RGB LED pins as output
  DDRB |= (1 << DDB6);  // Red LED (pin 12)
  DDRB |= (1 << DDB5);  // Green LED (pin 11)
  DDRB |= (1 << DDB4);  // Blue LED (pin 10)
#endif /* ENABLE_LCD */
#endif /* ENABLE_NEOPIXEL */

#ifdef ENABLE_RTC
  // Start RTC
  RTCStart();

  // Set Date/Time Callback Funtion
  SdFile::dateTimeCallback(dateTime);
#endif /* ENABLE_RTC */

#ifdef ENABLE_OLED
  display.begin();
  //isplay.setContrast(40);
  display.setFont(u8g2_font_haxrcorp4089_tr);
#endif /* ENABLE_OLED */

#ifdef ENABLE_SERIAL
  // Serial Begin
  Serial.begin(9600);
  Serial.println(FS(FSTRING_EMPTY));
  Serial.println(F("Cartridge Reader"));
  Serial.println(F("2024 github.com/sanni"));
  // LED Error
  rgbLed(blue_color);
#endif /* ENABLE_SERIAL */

  // Init SD card
  if (!sd.begin(SS)) {
    display_Clear();
#ifdef ENABLE_VSELECT
    print_STR(sd_error_STR, 1);
    println_Msg(FS(FSTRING_EMPTY));
    println_Msg(F("Press button to enable 5V for"));
    println_Msg(F("  updating firmware..."));
    display_Update();
    wait();
    display_Clear();
    setVoltage(VOLTS_SET_5V);  // Set voltage high for flashing
    println_Msg(F(" ======== UPDATE MODE ======== "));
    println_Msg(F("Waiting for update..."));
    println_Msg(FS(FSTRING_EMPTY));
    println_Msg(F("Press button to cancel/restart."));
    display_Update();
    wait();
    resetArduino();
#else  /* !ENABLE_VSELECT */
    print_FatalError(sd_error_STR);
#endif /* ENABLE_VSELECT */
  }

#if defined(ENABLE_CONFIG)
  configInit();
#if defined(ENABLE_GLOBAL_LOG)
  loggingEnabled = !!configGetLong(F("oscr.logging"), 1);
#endif /*ENABLE_CONFIG*/

  // Change LCD background if config specified
#ifdef ENABLE_NEOPIXEL
  setColor_RGB(0, 0, 100);
#endif /* ENABLE_NEOPIXEL */
#endif /* ENABLE_CONFIG */

#ifdef ENABLE_GLOBAL_LOG
  if (!myLog.open("OSCR_LOG.txt", O_RDWR | O_CREAT | O_APPEND)) {
    print_FatalError(sd_error_STR);
  }
  println_Msg(FS(FSTRING_EMPTY));
#if defined(HW1)
  print_Msg(F("OSCR HW1"));
#elif defined(HW2)
  print_Msg(F("OSCR HW2"));
#elif defined(HW3)
  print_Msg(F("OSCR HW3"));
#elif defined(HW4)
  print_Msg(F("OSCR HW4"));
#elif defined(HW5)
  print_Msg(F("OSCR HW5"));
#elif defined(SERIAL_MONITOR)
  print_Msg(F("OSCR Serial"));
#endif /* HWn */
  print_Msg(FS(FSTRING_SPACE));
  println_Msg(FS(FSTRING_VERSION));
#endif /* ENABLE_GLOBAL_LOG */

  // Turn status LED on
  statusLED(true);

#if defined(ENABLE_3V3FIX)
  setClockScale(CLKSCALE_8MHZ);  // Set clock back to low after setup
#endif                           /* ENABLE_3V3FIX */

  // Start menu system
  mainMenu();
}

/******************************************
   Common I/O Functions
 *****************************************/
// Switch data pins to write
void dataOut() {
  DDRC = 0xFF;
}

// Switch data pins to read
void dataIn() {
  // Set to Input and activate pull-up resistors
  DDRC = 0x00;
  // Pullups
  PORTC = 0xFF;
}

/******************************************
   Helper Functions
 *****************************************/
// Set RGB color
void setColor_RGB(byte r, byte g, byte b) {
#if defined(ENABLE_NEOPIXEL)
#if defined(ENABLE_3V3FIX)
  if (clock == CS_8MHZ) return;
#endif
  // Dim Neopixel LEDs
  if (r >= 100) r = 100;
  if (g >= 100) g = 100;
  if (b >= 100) b = 100;

  pixels.clear();

#if defined(ENABLE_CONFIG)
  uint8_t lcdConfColor = configGetLong(F("lcd.confColor"));

  if (lcdConfColor > 0) {
    uint8_t lcdRed = configGetLong(F("lcd.red"));
    uint8_t lcdGreen = configGetLong(F("lcd.green"));
    uint8_t lcdBlue = configGetLong(F("lcd.blue"));

    pixels.setPixelColor(0, pixels.Color(lcdGreen, lcdRed, lcdBlue));
  } else {
    pixels.setPixelColor(0, pixels.Color(OPTION_LCD_BG_COLOR));
  }
#else  /* !ENABLE_CONFIG */
  pixels.setPixelColor(0, pixels.Color(OPTION_LCD_BG_COLOR));
#endif /* ENABLE_CONFIG */
  pixels.setPixelColor(1, pixels.Color(g, r, b));
  pixels.setPixelColor(2, pixels.Color(g, r, b));
  pixels.show();
#elif defined(ENABLE_CA_LED)
  // Set color of analog 4 Pin common anode RGB LED
  analogWrite(12, 255 - r);
  analogWrite(11, 255 - g);
  analogWrite(10, 255 - b);
#else
  // Set color of analog 4 Pin common cathode RGB LED
  analogWrite(12, r);
  analogWrite(11, g);
  analogWrite(10, b);
#endif
}

// Extract ASCII printable characters from input, collapsing underscores and spaces.
// Use when extracting titles from cartridges, to build a rom title.
byte buildRomName(char* output, const byte* input, byte length) {
  byte input_char;
  byte output_len = 0;
  for (unsigned int i = 0; i < length; i++) {
    input_char = input[i];
    if (isprint(input_char) && input_char != '<' && input_char != '>' && input_char != ':' && input_char != '"' && input_char != '/' && input_char != '\\' && input_char != '|' && input_char != '?' && input_char != '*') {
      output[output_len++] = input_char;
    } else {
      if (output_len == 0 || output[output_len - 1] != '_') {
        output[output_len++] = '_';
      }
    }
  }
  while (
    output_len && (output[output_len - 1] == '_' || output[output_len - 1] == ' ')) {
    output_len--;
  }
  output[output_len] = 0;
  return output_len;
}

// Converts a progmem array into a ram array
void convertPgm(const char* const pgmOptions[], byte numArrays) {
  for (int i = 0; i < numArrays; i++) {
    strlcpy_P(menuOptions[i], (char*)pgm_read_word(&(pgmOptions[i])), 20);
  }
}

void _print_Error(void) {
  errorLvl = 1;
  rgbLed(red_color);
  display_Update();
}

void print_Error(const __FlashStringHelper* errorMessage) {
  println_Msg(errorMessage);
  _print_Error();
}

void print_Error(byte errorMessage) {
  print_STR(errorMessage, 1);
  _print_Error();
}

void print_Error(int errorMessage) {
  print_STR(errorMessage, 1);
  _print_Error();
}

void _print_FatalError(void) {
  println_Msg(FS(FSTRING_EMPTY));
  print_STR(press_button_STR, 1);
  display_Update();
  wait();
  resetArduino();
}

void print_FatalError(const __FlashStringHelper* errorMessage) {
  print_Error(errorMessage);
  _print_FatalError();
}

void print_FatalError(byte errorMessage) {
  print_Error(errorMessage);
  _print_FatalError();
}

void wait() {
  // Switch status LED off
  statusLED(false);
#if defined(ENABLE_LCD)
  wait_btn();
#elif defined(ENABLE_OLED)
  wait_btn();
#elif defined(ENABLE_SERIAL)
  wait_serial();
#endif
}

#ifdef ENABLE_GLOBAL_LOG
// Copies the last part of the current log file to the dump folder
void save_log() {
  // Last found position
  uint64_t lastPosition = 0;

  // Go to first line of log
  myLog.rewind();

  // Find location of OSCR string to determine start of current log
  char tempStr[5];
  while (myLog.available()) {
    // Read first 4 chars of line
    tempStr[0] = myLog.read();

    // Check if it's an empty line
    if (tempStr[0] == '\r') {
      // skip \n
      myLog.read();
    } else {
      // Read more lines
      tempStr[1] = myLog.read();
      tempStr[2] = myLog.read();
      tempStr[3] = myLog.read();
      tempStr[4] = '\0';
      char str_buf;

      // Skip rest of line
      while (myLog.available()) {
        str_buf = myLog.read();

        //break out of loop if CRLF is found
        if (str_buf == '\r') {
          myLog.read();  //dispose \n because \r\n
          break;
        }
      }

      // If string is OSCR remember position in file and test if it's the lastest log entry
      if (strncmp(tempStr, "OSCR", 4) == 0) {
        // Check if current position is newer as old position
        if (myLog.position() > lastPosition) {
          lastPosition = myLog.position();
        }
      }
    }
  }
  // Go to position of last log entry
  myLog.seek(lastPosition - 16);

  // Copy log from there to dump dir
  sd.chdir(folder);
  strcpy(fileName, romName);
  strcat(fileName, ".txt");
  if (!myFile.open(fileName, O_RDWR | O_CREAT)) {
    print_FatalError(sd_error_STR);
  }

  while (myLog.available()) {
    if (myLog.available() >= 512) {
      for (word i = 0; i < 512; i++) {
        sdBuffer[i] = myLog.read();
      }
      myFile.write(sdBuffer, 512);
    } else {
      int i = 0;
      for (; i < myLog.available(); i++) {
        sdBuffer[i] = myLog.read();
      }
      myFile.write(sdBuffer, i);
    }
  }
  // Close the file:
  myFile.close();
}
#endif

#ifdef ENABLE_GLOBAL_LOG
void println_Log(const __FlashStringHelper* string) {
  myLog.println(string);
}
#endif

void print_Msg(const __FlashStringHelper* string) {
#if (defined(ENABLE_LCD) || defined(ENABLE_OLED))
  display.print(string);
#endif
#ifdef ENABLE_SERIAL
  Serial.print(string);
#endif
#ifdef ENABLE_GLOBAL_LOG
  if (!dont_log && loggingEnabled) myLog.print(string);
#endif
}

void print_Msg(const char myString[]) {
#if (defined(ENABLE_LCD) || defined(ENABLE_OLED))
  // test for word wrap
  if ((display.tx + strlen(myString) * 6) > 128) {
    unsigned int strPos = 0;
    // Print until end of display
    while (display.tx < 122) {
      display.print(myString[strPos]);
      strPos++;
    }
    // Newline
    display.setCursor(0, display.ty + 8);
    // Print until end of display and ignore remaining characters
    while ((strPos < strlen(myString)) && (display.tx < 122)) {
      display.print(myString[strPos]);
      strPos++;
    }
  } else {
    display.print(myString);
  }
#endif
#ifdef ENABLE_SERIAL
  Serial.print(myString);
#endif
#ifdef ENABLE_GLOBAL_LOG
  if (!dont_log && loggingEnabled) myLog.print(myString);
#endif
}

void print_Msg(long unsigned int message) {
#if (defined(ENABLE_LCD) || defined(ENABLE_OLED))
  display.print(message);
#endif
#ifdef ENABLE_SERIAL
  Serial.print(message);
#endif
#ifdef ENABLE_GLOBAL_LOG
  if (!dont_log && loggingEnabled) myLog.print(message);
#endif
}

void print_Msg(byte message, int outputFormat) {
#if (defined(ENABLE_LCD) || defined(ENABLE_OLED))
  display.print(message, outputFormat);
#endif
#ifdef ENABLE_SERIAL
  Serial.print(message, outputFormat);
#endif
#ifdef ENABLE_GLOBAL_LOG
  if (!dont_log && loggingEnabled) myLog.print(message, outputFormat);
#endif
}

void print_Msg(word message, int outputFormat) {
#if (defined(ENABLE_LCD) || defined(ENABLE_OLED))
  display.print(message, outputFormat);
#endif
#ifdef ENABLE_SERIAL
  Serial.print(message, outputFormat);
#endif
#ifdef ENABLE_GLOBAL_LOG
  if (!dont_log && loggingEnabled) myLog.print(message, outputFormat);
#endif
}

void print_Msg(int message, int outputFormat) {
#if (defined(ENABLE_LCD) || defined(ENABLE_OLED))
  display.print(message, outputFormat);
#endif
#ifdef ENABLE_SERIAL
  Serial.print(message, outputFormat);
#endif
#ifdef ENABLE_GLOBAL_LOG
  if (!dont_log && loggingEnabled) myLog.print(message, outputFormat);
#endif
}

void print_Msg(long unsigned int message, int outputFormat) {
#if (defined(ENABLE_LCD) || defined(ENABLE_OLED))
  display.print(message, outputFormat);
#endif
#ifdef ENABLE_SERIAL
  Serial.print(message, outputFormat);
#endif
#ifdef ENABLE_GLOBAL_LOG
  if (!dont_log && loggingEnabled) myLog.print(message, outputFormat);
#endif
}

void print_Msg(String string) {
#if (defined(ENABLE_LCD) || defined(ENABLE_OLED))
  display.print(string);
#endif
#ifdef ENABLE_SERIAL
  Serial.print(string);
#endif
#ifdef ENABLE_GLOBAL_LOG
  if (!dont_log && loggingEnabled) myLog.print(string);
#endif
}

void print_Msg_PaddedHexByte(byte message) {
  if (message < 16) print_Msg(0, HEX);
  print_Msg(message, HEX);
}

void print_Msg_PaddedHex16(word message) {
  print_Msg_PaddedHexByte((message >> 8) & 0xFF);
  print_Msg_PaddedHexByte((message >> 0) & 0xFF);
}

void print_Msg_PaddedHex32(unsigned long message) {
  print_Msg_PaddedHexByte((message >> 24) & 0xFF);
  print_Msg_PaddedHexByte((message >> 16) & 0xFF);
  print_Msg_PaddedHexByte((message >> 8) & 0xFF);
  print_Msg_PaddedHexByte((message >> 0) & 0xFF);
}
void println_Msg(String string) {
#if (defined(ENABLE_LCD) || defined(ENABLE_OLED))
  display.print(string);
  display.setCursor(0, display.ty + 8);
#endif
#ifdef ENABLE_SERIAL
  Serial.println(string);
#endif
#ifdef ENABLE_GLOBAL_LOG
  if (!dont_log && loggingEnabled) myLog.println(string);
#endif
}

void println_Msg(byte message, int outputFormat) {
#if (defined(ENABLE_LCD) || defined(ENABLE_OLED))
  display.print(message, outputFormat);
  display.setCursor(0, display.ty + 8);
#endif
#ifdef ENABLE_SERIAL
  Serial.println(message, outputFormat);
#endif
#ifdef ENABLE_GLOBAL_LOG
  if (!dont_log && loggingEnabled) myLog.println(message, outputFormat);
#endif
}

void println_Msg(const char myString[]) {
#if (defined(ENABLE_LCD) || defined(ENABLE_OLED))
  // test for word wrap
  if ((display.tx + strlen(myString) * 6) > 128) {
    unsigned int strPos = 0;
    // Print until end of display
    while ((display.tx < 122) && (myString[strPos] != '\0')) {
      display.print(myString[strPos]);
      strPos++;
    }
    // Newline
    display.setCursor(0, display.ty + 8);
    // Print until end of display and ignore remaining characters
    while ((strPos < strlen(myString)) && (display.tx < 122) && (myString[strPos] != '\0')) {
      display.print(myString[strPos]);
      strPos++;
    }
  } else {
    display.print(myString);
  }
  display.setCursor(0, display.ty + 8);
#endif
#ifdef ENABLE_SERIAL
  Serial.println(myString);
#endif
#ifdef ENABLE_GLOBAL_LOG
  if (!dont_log && loggingEnabled) myLog.println(myString);
#endif
}

void println_Msg(const __FlashStringHelper* string) {
#if (defined(ENABLE_LCD) || defined(ENABLE_OLED))
  display.print(string);
  display.setCursor(0, display.ty + 8);
#endif
#ifdef ENABLE_SERIAL
  Serial.println(string);
#endif
#ifdef ENABLE_GLOBAL_LOG
  char myBuffer[15];
  strlcpy_P(myBuffer, (char*)string, 15);
  if ((strncmp(myBuffer, "Press Button...", 14) != 0) && (strncmp(myBuffer, "Select file", 10) != 0)) {
    if (!dont_log && loggingEnabled) myLog.println(string);
  }
#endif
}

void println_Msg(long unsigned int message) {
#if (defined(ENABLE_LCD) || defined(ENABLE_OLED))
  display.print(message);
  display.setCursor(0, display.ty + 8);
#endif
#ifdef ENABLE_SERIAL
  Serial.println(message);
#endif
#ifdef ENABLE_GLOBAL_LOG
  if (!dont_log && loggingEnabled) myLog.println(message);
#endif
}

void display_Update() {
#if (defined(ENABLE_LCD) || defined(ENABLE_OLED))
  display.updateDisplay();
#endif
#ifdef ENABLE_SERIAL
  delay(100);
#endif
#ifdef ENABLE_GLOBAL_LOG
  if (!dont_log && loggingEnabled) myLog.flush();
#endif
}

void display_Clear() {
#if (defined(ENABLE_LCD) || defined(ENABLE_OLED))
  display.clearDisplay();
  display.setCursor(0, 8);
#endif
#ifdef ENABLE_GLOBAL_LOG
  if (!dont_log && loggingEnabled) myLog.println(FS(FSTRING_EMPTY));
#endif
}

void display_Clear_Slow() {
#if (defined(ENABLE_LCD) || defined(ENABLE_OLED))
  display.setDrawColor(0);
  for (byte y = 0; y < 64; y++) {
    display.drawLine(0, y, 128, y);
  }
  display.setDrawColor(1);
  display.setCursor(0, 8);
#endif
}

/******************************************
  RGB LED
*****************************************/
void rgbLed(byte Color) {
  switch (Color) {
    case blue_color:
      setColor_RGB(0, 0, 255);
      break;
    case red_color:
      setColor_RGB(255, 0, 0);
      break;
    case purple_color:
      setColor_RGB(255, 0, 255);
      break;
    case green_color:
      setColor_RGB(0, 255, 0);
      break;
    case turquoise_color:
      setColor_RGB(0, 255, 255);
      break;
    case yellow_color:
      setColor_RGB(255, 255, 0);
      break;
    case white_color:
      setColor_RGB(255, 255, 255);
      break;
    case black_color:
      setColor_RGB(0, 0, 0);
      break;
  }
}

void blinkLED() {
#if defined(ENABLE_VSELECT)
  // Nothing
#elif defined(HW5)
  // 3mm LED on D38, front of PCB
  PORTD ^= (1 << 7);
#elif defined(ENABLE_OLED)
  // 5mm LED on D10, above SD slot
  PORTB ^= (1 << 4);
#elif defined(ENABLE_LCD)  // HW4
  // TX LED on D1, build-in
  PORTE ^= (1 << 1);
#elif defined(ENABLE_SERIAL)
  // 5mm LED on D10, above SD slot (HW3)
  PORTB ^= (1 << 4);  //HW4/HW5 LCD RST connects there now too
  // 3mm LED on D38, front of PCB (HW5)
  PORTB ^= (1 << 7);
#endif
}

#if defined(HW5) && !defined(ENABLE_VSELECT)
// 3mm LED on D38, front of PCB
void statusLED(boolean on) {
  if (!on)
    PORTD |= (1 << 7);
  else
    PORTD &= ~(1 << 7);
}
#else
void statusLED(boolean on __attribute__((unused))) {
}
#endif

/******************************************
  Menu system
*****************************************/
unsigned char question_box(const __FlashStringHelper* question, char answers[7][20], uint8_t num_answers, uint8_t default_choice) {
#if (defined(ENABLE_LCD) || defined(ENABLE_OLED))
  return questionBox_Display(question, answers, num_answers, default_choice);
#endif
#ifdef ENABLE_SERIAL
  return questionBox_Serial(question, answers, num_answers, default_choice);
#endif
}

#if defined(ENABLE_SERIAL)
// Serial Monitor
byte questionBox_Serial(const __FlashStringHelper* question __attribute__((unused)), char answers[7][20], uint8_t num_answers, uint8_t default_choice __attribute__((unused))) {
  // Print menu to serial monitor
  Serial.println(FS(FSTRING_EMPTY));
  for (byte i = 0; i < num_answers; i++) {
    Serial.print(i);
    Serial.print(F(")"));
    Serial.println(answers[i]);
  }
  // Wait for user input
  Serial.println(FS(FSTRING_EMPTY));
  Serial.println(F("Please browse pages with 'u'(up) and 'd'(down)"));
  Serial.println(F("and enter a selection by typing a number(0-6): _ "));
  Serial.println(FS(FSTRING_EMPTY));
  while (Serial.available() == 0) {
  }

  // Read the incoming byte:
  incomingByte = Serial.read() - 48;

  // Page up (u)
  if (incomingByte == 69) {
    if (currPage > 1) {
      lastPage = currPage;
      currPage--;
    } else {
      root = 1;
    }
  }

  // Page down (d)
  else if (incomingByte == 52) {
    if (numPages > currPage) {
      lastPage = currPage;
      currPage++;
    }
  }

  // Execute choice
  else if ((incomingByte >= 0) && (incomingByte < 7)) {
    numPages = 0;
  }

  // Print the received byte for validation e.g. in case of a different keyboard mapping
  //Serial.println(incomingByte);
  //Serial.println(FS(FSTRING_EMPTY));
  return incomingByte;
}
#endif

// OLED & LCD
#if (defined(ENABLE_LCD) || defined(ENABLE_OLED))
// Display a question box with selectable answers. Make sure default choice is in (0, num_answers]
unsigned char questionBox_Display(const __FlashStringHelper* question, char answers[7][20], uint8_t num_answers, uint8_t default_choice) {
  //clear the screen
  display.clearDisplay();
  display.updateDisplay();
  display.setCursor(0, 8);
  display.setDrawColor(1);

  // change the rgb led to the start menu color
  rgbLed(default_choice);

  // print menu
  display.println(question);
  display.setCursor(0, display.ty + 8);
  for (unsigned char i = 0; i < num_answers; i++) {
    // Add space for the selection dot
    display.print("   ");
    // Print menu item
    display.println(answers[i]);
    display.setCursor(0, display.ty + 8);
  }
  display.updateDisplay();

  // start with the default choice
  choice = default_choice;

  // draw selection box
  display.drawBox(1, 8 * choice + 11, 3, 3);
  display.updateDisplay();

  unsigned long idleTime = millis();
  byte currentColor = 0;

  // wait until user makes his choice
  while (1) {
    // Attract Mode
    if (millis() - idleTime > 300000) {
      if ((millis() - idleTime) % 4000 == 0) {
        if (currentColor < 5) {
          currentColor++;
          if (currentColor == 1) {
            currentColor = 2;  // skip red as that signifies an error to the user
          }
        } else {
          currentColor = 0;
        }
        rgbLed(currentColor);
      }
    }

    /* Check Button/rotary encoder
      1 click/clockwise rotation
      2 doubleClick/counter clockwise rotation
      3 hold/press
      4 longHold */
    uint8_t b = checkButton();

    // if button is pressed twice or rotary encoder turned left/counter clockwise
    if (b == 2) {
      idleTime = millis();

      // remove selection box
      display.setDrawColor(0);
      display.drawBox(1, 8 * choice + 11, 3, 3);
      display.setDrawColor(1);
      display.updateDisplay();

      // If cursor on top list entry
      if (choice == 0) {
        // On 2nd, 3rd, ... page go back one page
        if (currPage > 1) {
          lastPage = currPage;
          currPage--;
          break;
        }
        // In file browser go to root dir
        else if ((filebrowse == 1) && (root != 1)) {
          root = 1;
          break;
        }
        // Else go to bottom of list as a shortcut
        else {
          choice = num_answers - 1;
        }
      }
      // If not top entry go up/back one entry
      else {
        choice--;
      }

      // draw selection box
      display.drawBox(1, 8 * choice + 11, 3, 3);
      display.updateDisplay();

      // change RGB led to the color of the current menu option
      rgbLed(choice);
    }

    // go one down in the menu if the Cart Readers button is clicked shortly
    if (b == 1) {
      idleTime = millis();

      // remove selection box
      display.setDrawColor(0);
      display.drawBox(1, 8 * choice + 11, 3, 3);
      display.setDrawColor(1);
      display.updateDisplay();

      if ((choice == num_answers - 1) && (numPages > currPage)) {
        lastPage = currPage;
        currPage++;
        break;
      } else
        choice = (choice + 1) % num_answers;

      // draw selection box
      display.drawBox(1, 8 * choice + 11, 3, 3);
      display.updateDisplay();

      // change RGB led to the color of the current menu option
      rgbLed(choice);
    }

    // if the Cart Readers button is hold continiously leave the menu
    // so the currently highlighted action can be executed

    if (b == 3) {
      idleTime = millis();
      // All done
      numPages = 0;
      break;
    }

    checkUpdater();
  }

  // pass on user choice
  rgbLed(black_color);

#ifdef ENABLE_GLOBAL_LOG
  println_Msg(FS(FSTRING_EMPTY));
  print_Msg(F("[+] "));
  println_Msg(answers[choice]);
#endif

  return choice;
}
#endif

void checkUpdater() {
#if !defined(ENABLE_SERIAL) && defined(ENABLE_UPDATER)
  if (ClockedSerial.available() > 0) {
    String cmd = ClockedSerial.readStringUntil('\n');
    cmd.trim();
    if (cmd == "VERCHK") {  // VERCHK: Gets OSCR version and features
      delay(500);
      printVersionToSerial();
    } else if (cmd == "GETCLOCK") {  // GETCLOCK: Gets the MEGA's current clock speed.
#if defined(ENABLE_3V3FIX)
      ClockedSerial.print(F("Clock is running at "));
      ClockedSerial.print((clock == CS_16MHZ) ? 16UL : 8UL);
      ClockedSerial.println(F("MHz"));
#else                                               /* !ENABLE_3V3FIX */
      ClockedSerial.println(FS(FSTRING_MODULE_NOT_ENABLED));
#endif                                              /* ENABLE_3V3FIX */
    } else if (cmd.substring(1, 8) == "ETVOLTS") {  // (G/S)ETVOLTS: Get and set the voltage.
#if defined(ENABLE_VSELECT)
      if (cmd != "GETVOLTS") {
        switch (cmd.substring(9, 10).toInt()) {
          case 3: setVoltage(VOLTS_SET_3V3); break;
          case 5: setVoltage(VOLTS_SET_5V); break;
        }
      }
      ClockedSerial.print(F("Voltage is set to "));
      ClockedSerial.print((voltage == VOLTS_SET_5V) ? 5 : 3.3);
      ClockedSerial.println(F("V"));
#else  /* !ENABLE_VSELECT */
      ClockedSerial.println(FS(FSTRING_MODULE_NOT_ENABLED));
#endif /* ENABLE_VSELECT */
    }
    // RTC commands
    else if (cmd.substring(1, 7) == "ETTIME") {  // (G/S)ETTIME: Get and set the date/time.
#if defined(ENABLE_RTC)
      if (cmd != "GETTIME") {
        ClockedSerial.println(F("Setting Time..."));
        rtc.adjust(DateTime(cmd.substring(8).toInt()));
      }
      ClockedSerial.print(F("Current Time: "));
      ClockedSerial.println(RTCStamp());
#else  /* !ENABLE_RTC */
      ClockedSerial.println(FS(FSTRING_MODULE_NOT_ENABLED));
#endif /* ENABLE_RTC */
    } else {
      ClockedSerial.print(FS(FSTRING_OSCR));
      ClockedSerial.println(F(": Unknown Command"));
    }
  }
#endif
}

/******************************************
  User Control
*****************************************/
// Using Serial Monitor
#if defined(ENABLE_SERIAL)
uint8_t checkButton() {
  while (Serial.available() == 0) {
  }
  incomingByte = Serial.read() - 48;

  //Next
  if (incomingByte == 52) {
    return 1;
  }

  //Previous
  else if (incomingByte == 69) {
    return 2;
  }

  //Selection
  else if ((incomingByte == 240) || (incomingByte == -16) || (incomingByte == 0)) {
    return 3;
  }

  return 0;
}

void wait_serial() {
  if (errorLvl) {
    errorLvl = 0;
  }
  while (Serial.available() == 0) {
  }
  incomingByte = Serial.read() - 48;
  /* if ((incomingByte == 53) && (fileName[0] != '\0')) {
      // Open file on sd card
      sd.chdir(folder);
      if (myFile.open(fileName, O_READ)) {
        // Get rom size from file
        fileSize = myFile.fileSize();

        // Send filesize
        char tempStr[16];
        sprintf(tempStr, "%d", fileSize);
        Serial.write(tempStr);

        // Wait for ok
        while (Serial.available() == 0) {
        }

        // Send file
        for (unsigned long currByte = 0; currByte < fileSize; currByte++) {
          // Blink led
          if (currByte % 1024 == 0)
            blinkLED();
          Serial.write(myFile.read());
        }
        // Close the file:
        myFile.close();
      }
      else {
        print_FatalError(open_file_STR);
      }
    }*/
}
#endif

// Using one or two push buttons (HW1/HW2/HW3)
#if defined(ENABLE_OLED)
// Read button state
uint8_t checkButton() {
#ifdef ENABLE_BUTTON2
  byte eventButton2 = checkButton2();
  if ((eventButton2 > 0) && (eventButton2 < 2))
    return 3;
  else if (eventButton2 > 2)
    return 4;
#endif
  return (checkButton1());
}

// Read button 1
uint8_t checkButton1() {
  uint8_t event = 0;

  // Read the state of the button (PD7)
  buttonVal1 = (PIND & (1 << 7));
  // Button pressed down
  if (buttonVal1 == LOW && buttonLast1 == HIGH && (millis() - upTime1) > debounce) {
    downTime1 = millis();
    ignoreUp1 = false;
    waitForUp1 = false;
    singleOK1 = true;
    holdEventPast1 = false;
    longholdEventPast1 = false;
    if ((millis() - upTime1) < DCgap && DConUp1 == false && DCwaiting1 == true) DConUp1 = true;
    else DConUp1 = false;
    DCwaiting1 = false;
  }
  // Button released
  else if (buttonVal1 == HIGH && buttonLast1 == LOW && (millis() - downTime1) > debounce) {
    if (!ignoreUp1) {
      upTime1 = millis();
      if (DConUp1 == false) DCwaiting1 = true;
      else {
        event = 2;
        DConUp1 = false;
        DCwaiting1 = false;
        singleOK1 = false;
      }
    }
  }
  // Test for normal click event: DCgap expired
  if (buttonVal1 == HIGH && (millis() - upTime1) >= DCgap && DCwaiting1 == true && DConUp1 == false && singleOK1 == true) {
    event = 1;
    DCwaiting1 = false;
  }
  // Test for hold
  if (buttonVal1 == LOW && (millis() - downTime1) >= holdTime) {
    // Trigger "normal" hold
    if (!holdEventPast1) {
      event = 3;
      waitForUp1 = true;
      ignoreUp1 = true;
      DConUp1 = false;
      DCwaiting1 = false;
      //downTime1 = millis();
      holdEventPast1 = true;
    }
    // Trigger "long" hold
    if ((millis() - downTime1) >= longHoldTime) {
      if (!longholdEventPast1) {
        event = 4;
        longholdEventPast1 = true;
      }
    }
  }
  buttonLast1 = buttonVal1;
  return event;
}

// Read button 2
uint8_t checkButton2() {
  uint8_t event = 0;

  // Read the state of the button (PG2)
  buttonVal2 = (PING & (1 << 2));
  // Button pressed down
  if (buttonVal2 == LOW && buttonLast2 == HIGH && (millis() - upTime2) > debounce) {
    downTime2 = millis();
    ignoreUp2 = false;
    waitForUp2 = false;
    singleOK2 = true;
    holdEventPast2 = false;
    longholdEventPast2 = false;
    if ((millis() - upTime2) < DCgap && DConUp2 == false && DCwaiting2 == true) DConUp2 = true;
    else DConUp2 = false;
    DCwaiting2 = false;
  }
  // Button released
  else if (buttonVal2 == HIGH && buttonLast2 == LOW && (millis() - downTime2) > debounce) {
    if (!ignoreUp2) {
      upTime2 = millis();
      if (DConUp2 == false) DCwaiting2 = true;
      else {
        event = 2;
        DConUp2 = false;
        DCwaiting2 = false;
        singleOK2 = false;
      }
    }
  }
  // Test for normal click event: DCgap expired
  if (buttonVal2 == HIGH && (millis() - upTime2) >= DCgap && DCwaiting2 == true && DConUp2 == false && singleOK2 == true) {
    event = 1;
    DCwaiting2 = false;
  }
  // Test for hold
  if (buttonVal2 == LOW && (millis() - downTime2) >= holdTime) {
    // Trigger "normal" hold
    if (!holdEventPast2) {
      event = 3;
      waitForUp2 = true;
      ignoreUp2 = true;
      DConUp2 = false;
      DCwaiting2 = false;
      //downTime2 = millis();
      holdEventPast2 = true;
    }
    // Trigger "long" hold
    if ((millis() - downTime2) >= longHoldTime) {
      if (!longholdEventPast2) {
        event = 4;
        longholdEventPast2 = true;
      }
    }
  }
  buttonLast2 = buttonVal2;
  return event;
}

// Wait for user to push button
void wait_btn() {
  // Change led to green
  if (errorLvl == 0)
    rgbLed(green_color);

  while (1) {
    // get input button
    uint8_t b = checkButton();

    // if the cart readers input button is pressed shortly
    if (b == 1) {
      errorLvl = 0;
      break;
    }

    // if the cart readers input button is pressed long
    if (b == 3) {
      if (errorLvl) {
        errorLvl = 0;
      }
      break;
    }

    checkUpdater();
  }
}
#endif

// Using rotary encoder (HW4/HW5)
#if (defined(ENABLE_LCD) && defined(ENABLE_ROTARY))
// Read encoder state
uint8_t checkButton() {
  // Read rotary encoder
  encoder.tick();
  int newPos = encoder.getPosition();
  // Read button
  boolean reading = (PING & (1 << PING2)) >> PING2;

  // Check if rotary encoder has changed
  if (rotaryPos != newPos) {
    int rotaryDir = (int)encoder.getDirection();
    rotaryPos = newPos;
    if (rotaryDir == 1) {
      return 1;
    } else if (rotaryDir == -1) {
      return 2;
    }
  } else if (reading != buttonState) {
    if (reading != lastButtonState) {
      lastDebounceTime = millis();
      lastButtonState = reading;
    } else if ((millis() - lastDebounceTime) > debounceDelay) {
      buttonState = reading;
      // Button was pressed down
      if (buttonState == 0) {
        rgbLed(black_color);
        unsigned long pushTime = millis();
        // Wait until button was let go again
        while ((PING & (1 << PING2)) >> PING2 == 0) {
          // Signal long press delay reached
          if ((millis() - pushTime) > 2000) {
            rgbLed(green_color);
          }
        }

        // 2 second long press
        if ((millis() - pushTime) > 2000) {
          return 4;
        }
        // normal press
        else {
          return 3;
        }
      }
    }
  }
  return 0;
}

// Wait for user to push button
void wait_btn() {
  // Change led to green
  if (errorLvl == 0)
    rgbLed(green_color);

  while (1) {
    // get input button
    uint8_t b = checkButton();

    // if the cart readers input button is pressed shortly
    if (b == 1) {
      errorLvl = 0;
      break;
    }

    // if the cart readers input button is pressed long
    if (b == 3) {
      if (errorLvl) {
        errorLvl = 0;
      }
      break;
    }

    checkUpdater();
  }
}

// Wait for user to rotate knob
void wait_encoder() {
  // Change led to green
  if (errorLvl == 0)
    rgbLed(green_color);

  while (1) {
    // Get rotary encoder
    encoder.tick();
    int newPos = encoder.getPosition();

    if (rotaryPos != newPos) {
      rotaryPos = newPos;
      errorLvl = 0;
      break;
    }
  }
}
#endif

/******************************************
  Filebrowser Module
*****************************************/
void fileBrowser(const __FlashStringHelper* browserTitle) {
  char fileNames[7][FILENAME_LENGTH];
  int currFile;
  FsFile myDir;
  div_t page_layout;

  filebrowse = 1;

  // Root
  filePath[0] = '/';
  filePath[1] = '\0';

  // Temporary char array for filename
  char nameStr[FILENAME_LENGTH];

browserstart:

  // Print title
  println_Msg(browserTitle);

  // Set currFile back to 0
  currFile = 0;
  currPage = 1;
  lastPage = 1;

  // Open filepath directory
  if (!myDir.open(filePath)) {
    display_Clear();
    print_FatalError(sd_error_STR);
  }

  // Count files in directory
  while (myFile.openNext(&myDir, O_READ)) {
    if (!myFile.isHidden() && (myFile.isDir() || myFile.isFile())) {
      currFile++;
    }
    myFile.close();
  }
  myDir.close();

  page_layout = div(currFile, 7);
  numPages = page_layout.quot + 1;

  // Fill the array "answers" with 7 options to choose from in the file browser
  char answers[7][20];

page:

  // If there are less than 7 entries, set count to that number so no empty options appear
  byte count = currPage == numPages ? page_layout.rem : 7;

  // Open filepath directory
  if (!myDir.open(filePath)) {
    display_Clear();
    print_FatalError(sd_error_STR);
  }

  int countFile = 0;
  byte i = 0;
  // Cycle through all files
  while ((myFile.openNext(&myDir, O_READ)) && (i < 8)) {
    // Get name of file
    myFile.getName(nameStr, FILENAME_LENGTH);

    // Ignore if hidden
    if (myFile.isHidden()) {
    }
    // Directory
    else if (myFile.isDir()) {
      if (countFile == ((currPage - 1) * 7 + i)) {
        snprintf(fileNames[i], FILENAME_LENGTH, "%s%s", "/", nameStr);
        i++;
      }
      countFile++;
    }
    // File
    else if (myFile.isFile()) {
      if (countFile == ((currPage - 1) * 7 + i)) {
        snprintf(fileNames[i], FILENAME_LENGTH, "%s", nameStr);
        i++;
      }
      countFile++;
    }
    myFile.close();
  }
  myDir.close();

  for (byte i = 0; i < 8; i++) {
    // Copy short string into fileOptions
    snprintf(answers[i], FILEOPTS_LENGTH, "%s", fileNames[i]);
  }

  // Create menu with title and 1-7 options to choose from
  unsigned char answer = question_box(browserTitle, answers, count, 0);

  // Check if the page has been switched
  if (currPage != lastPage) {
    lastPage = currPage;
    goto page;
  }

  // Check if we are supposed to go back to the root dir
  if (root) {
    // Change working dir to root
    filePath[0] = '/';
    filePath[1] = '\0';
    sd.chdir("/");
    // Start again
    root = 0;
    goto browserstart;
  }

  // wait for user choice to come back from the question box menu
  switch (answer) {
    case 0:
      strncpy(fileName, fileNames[0], FILENAME_LENGTH - 1);
      break;

    case 1:
      strncpy(fileName, fileNames[1], FILENAME_LENGTH - 1);
      break;

    case 2:
      strncpy(fileName, fileNames[2], FILENAME_LENGTH - 1);
      break;

    case 3:
      strncpy(fileName, fileNames[3], FILENAME_LENGTH - 1);
      break;

    case 4:
      strncpy(fileName, fileNames[4], FILENAME_LENGTH - 1);
      break;

    case 5:
      strncpy(fileName, fileNames[5], FILENAME_LENGTH - 1);
      break;

    case 6:
      strncpy(fileName, fileNames[6], FILENAME_LENGTH - 1);
      break;

      //case 7:
      // File import
      //break;
  }

  // Add directory to our filepath if we just entered a new directory
  if (fileName[0] == '/') {
    // add dirname to path
    strcat(filePath, fileName);
    // Remove / from dir name
    char* dirName = fileName + 1;
    // Change working dir
    sd.chdir(dirName);
    // Start browser in new directory again
    goto browserstart;
  } else {
    // Afer everything is done change SD working directory back to root
    sd.chdir("/");
  }
  filebrowse = 0;
}

/******************************************
  Main loop
*****************************************/
void loop() {
  switch (mode) {
#ifdef ENABLE_N64
    case CORE_N64_CART: return n64CartMenu();
    case CORE_N64_CONTROLLER: return n64ControllerMenu();
#endif
#ifdef ENABLE_SNES
    case CORE_SNES: return snesMenu();
#endif
#ifdef ENABLE_SFM
    case CORE_SFM: return sfmMenu();
#ifdef ENABLE_FLASH
    case CORE_SFM_FLASH: return sfmFlashMenu();
#endif
    case CORE_SFM_GAME: return sfmGameOptions();
#endif
#ifdef ENABLE_GBX
    case CORE_GB: return gbMenu();
    case CORE_GBA: return gbaMenu();
    case CORE_GBM: return gbmMenu();
    case CORE_GB_GBSMART: return gbSmartMenu();
    case CORE_GB_GBSMART_FLASH: return gbSmartFlashMenu();
    case CORE_GB_GBSMART_GAME: return gbSmartGameOptions();
#endif
#ifdef ENABLE_FLASH
    case CORE_FLASH8: return flashromMenu8();
#ifdef ENABLE_FLASH16
    case CORE_FLASH16: return flashromMenu16();
    case CORE_EPROM: return epromMenu();
#endif
#endif
#ifdef ENABLE_MD
    case CORE_MD_CART: return mdCartMenu();
    case CORE_SEGA_CD: return segaCDMenu();
#endif
#ifdef ENABLE_PCE
    case CORE_PCE: return pceMenu();
#endif
#ifdef ENABLE_SV
    case CORE_SV: return svMenu();
#endif
#ifdef ENABLE_NES
    case CORE_NES: return nesMenu();
#endif
#ifdef ENABLE_SMS
    case CORE_SMS: return smsMenu();
#endif
#ifdef ENABLE_WS
    case CORE_WS: return wsMenu();
#endif
#ifdef ENABLE_NGP
    case CORE_NGP: return ngpMenu();
#endif
#ifdef ENABLE_INTV
    case CORE_INTV: return intvMenu();
#endif
#ifdef ENABLE_COLV
    case CORE_COL: return colMenu();
#endif
#ifdef ENABLE_VBOY
    case CORE_VBOY: return vboyMenu();
#endif
#ifdef ENABLE_WSV
    case CORE_WSV: return wsvMenu();
#endif
#ifdef ENABLE_PCW
    case CORE_PCW: return pcwMenu();
#endif
#ifdef ENABLE_ODY2
    case CORE_ODY2: return ody2Menu();
#endif
#ifdef ENABLE_ARC
    case CORE_ARC: return arcMenu();
#endif
#ifdef ENABLE_FAIRCHILD
    case CORE_FAIRCHILD: return fairchildMenu();
#endif
#ifdef ENABLE_SUPRACAN
    case CORE_SUPRACAN: return suprAcanMenu();
#endif
#ifdef ENABLE_MSX
    case CORE_MSX: return msxMenu();
#endif
#ifdef ENABLE_POKE
    case CORE_POKE: return pokeMenu();
#endif
#ifdef ENABLE_LOOPY
    case CORE_LOOPY: return loopyMenu();
#endif
#ifdef ENABLE_C64
    case CORE_C64: return c64Menu();
#endif
#ifdef ENABLE_2600
    case CORE_2600: return a2600Menu();
#endif
#ifdef ENABLE_5200
    case CORE_5200: return a5200Menu();
#endif
#ifdef ENABLE_7800
    case CORE_7800: return a7800Menu();
#endif
#ifdef ENABLE_LYNX
    case CORE_LYNX: return lynxMenu();
#endif
#ifdef ENABLE_VECTREX
  	case CORE_VECTREX: return vectrexMenu();
#endif
#ifdef ENABLE_JAGUAR
  	case CORE_JAGUAR: return jagMenu();
#endif
#ifdef ENABLE_ST
    case CORE_ST: return stMenu();
#endif
#ifdef ENABLE_GPC
    case CORE_GPC: return gpcMenu();
#endif
#ifdef ENABLE_ATARI8
    case CORE_ATARI8: return atari8Menu();
#endif
#ifdef ENABLE_BALLY
    case CORE_BALLY: return ballyMenu();
#endif
#ifdef ENABLE_LJ
    case CORE_LJ: return ljMenu();
#endif
#ifdef ENABLE_LJPRO
    case CORE_LJPRO: return ljproMenu();
#endif
#ifdef ENABLE_PV1000
    case CORE_PV1000: return pv1000Menu();
#endif
#ifdef ENABLE_VIC20
    case CORE_VIC20: return vic20Menu();
#endif
#ifdef ENABLE_LEAP
    case CORE_LEAP: return leapMenu();
#endif
#ifdef ENABLE_RCA
    case CORE_RCA: return rcaMenu();
#endif
#ifdef ENABLE_TI99
    case CORE_TI99: return ti99Menu();
#endif
#ifdef ENABLE_PYUUTA
    case CORE_PYUUTA: return pyuutaMenu();
#endif
#ifdef ENABLE_TRS80
    case CORE_TRS80: return trs80Menu();
#endif
#ifdef ENABLE_VSMILE
    case CORE_VSMILE: return vsmileMenu();
#endif
    case CORE_MAX: return resetArduino();
  }
}

//******************************************
// End of File
//******************************************