OpenLog.ino

/*
 12-3-09
 Nathan Seidle
 SparkFun Electronics

 OpenLog hardware and firmware are released under the Creative Commons Share Alike v3.0 license.
 http://creativecommons.org/licenses/by-sa/3.0/
 Feel free to use, distribute, and sell varients of OpenLog. All we ask is that you include attribution of 'Based on OpenLog by SparkFun'.

 OpenLog is based on the work of Bill Greiman and sdfatlib: https://github.com/greiman/SdFat-beta

 OpenLog is a simple serial logger based on the ATmega328 running at 16MHz. The whole purpose of this
 logger was to create a logger that just powered up and worked. OpenLog ships with an Arduino/Optiboot
 115200bps serial bootloader running at 16MHz so you can load new firmware with a simple serial
 connection.

 OpenLog has progressed significantly over the past three years. Please see CHANGELOG.md or GitHub commits
 for a full trip down memory lane.

 OpenLog automatically works with 512MB to 64GB micro/SD cards.

 OpenLog runs at 9600bps by default. This is configurable to 1200, 2400, 4800, 9600, 19200, 38400, 57600, and 115200bps. You can alter
 all settings including baud rate and escape characters by editing config.txt found on OpenLog.

 Type '?' to get a list of supported commands.

 During power up, you will see '12<'. '1' indicates the serial connection is established. '2' indicates
 the SD card has been successfully initialized. '<' indicates OpenLog is ready to receive serial characters.

 Recording constant 115200bps datastreams are supported. Throw it everything you've got! To acheive this maximum record rate, please use the
 SD card formatter from : http://www.sdcard.org/consumers/formatter/. The fewer files on the card, the faster OpenLog is able to begin logging.
 200 files is ok. 2GB worth of music and pictures is not.

 To a lower dir, use 'cd ..' instead of 'cd..'.

 Only standard 8.3 file names are supported. "12345678.123" is acceptable. "123456789.123" is not.

 All file names are pushed to upper case. "NewLog.txt" will become "NEWLOG.TXT".

 Type 'set' to enter baud rate configuration menu. Select the baud rate and press enter. You will then
 see a message 'Going to 9600bps...' or some such message. You will need to power down OpenLog, change
 your system UART settings to match the new OpenLog baud rate and then power OpenLog back up.

 If you get OpenLog stuck into an unknown baudrate, there is a safety mechanism built-in. Tie the RX pin
 to ground and power up OpenLog. You should see the LEDs blink back and forth for 2 seconds, then blink
 in unison. Now power down OpenLog and remove the RX/GND jumper. OpenLog is now reset to 9600bps.

 Please note: The preloaded Optiboot serial bootloader is 0.5k, and begins at 0x7E00 (32,256). If the code is
 larger than 32,256 bytes, you will get verification errors during serial bootloading.

 OpenLog regularly shuts down to conserve power. If after 0.5 seconds no characters are received, OpenLog will record 
 any unsaved characters and go to sleep. OpenLog will automatically wake up and continue logging the instant a 
 new character is received.

 1.55mA idle
 15mA actively writing

 Input voltage on VCC can be 3.3 to 12V. Input voltage on RX-I pin must not exceed 6V. Output voltage on
 TX-O pin will not be greater than 3.3V. This may cause problems with some systems - for example if your
 attached microcontroller requires 4V minimum for serial communication (this is rare).

 */

#define __PROG_TYPES_COMPAT__ //Needed to get SerialPort.h to work in Arduino 1.6.x

#include <SPI.h>
#include <SdFat.h> //We do not use the built-in SD.h file because it calls Serial.print
#include <SerialPort.h> //This is a new/beta library written by Bill Greiman. You rock Bill!
#include <EEPROM.h>
#include <FreeStack.h> //Allows us to print the available stack/RAM size

SerialPort<0, 512, 0> NewSerial;
//<port #, RX buffer size, TX buffer size>
//We set the TX buffer to zero because we will be spending most of our 
//time needing to buffer the incoming (RX) characters.

//This is the array within the append file routine
//We have to keep SerialPort buffer sizes reasonable so that when we drop to
//the command shell we have RAM available for the various commands like append
#define LOCAL_BUFF_SIZE 255 //Must not be larger than charsToRecord variable size which is currently a byte
//512/256 shell works, 5/5 logs passed
//800/128 shell works, 3/5 logs passed
//672/256 shell works, 2/5 logs passed
//722/256 shell fails
//850/128 shell fails

#include <avr/sleep.h> //Needed for sleep_mode
#include <avr/power.h> //Needed for powering down perihperals such as the ADC/TWI and Timers

#define SD_CHIP_SELECT 10 //On OpenLog this is pin 10

//Debug turns on (1) or off (0) a bunch of verbose debug statements. Normally use (0)
//#define DEBUG  1
#define DEBUG  0

void(* Reset_AVR) (void) = 0; //Way of resetting the ATmega

#define CFG_FILENAME "config.txt" //This is the name of the file that contains the unit settings

#define MAX_CFG "115200,103,214,0,1,1,0\0" //= 115200 bps, escape char of ASCII(103), 214 times, new log mode, verbose on, echo on, ignore RX false. 
#define CFG_LENGTH (strlen(MAX_CFG) + 1) //Length of text found in config file. strlen ignores \0 so we have to add it back 
#define SEQ_FILENAME "SEQLOG00.TXT" //This is the name for the file when you're in sequential mode

//Internal EEPROM locations for the user settings
#define LOCATION_SYSTEM_SETTING		  0x02
#define LOCATION_FILE_NUMBER_LSB	  0x03
#define LOCATION_FILE_NUMBER_MSB	  0x04
#define LOCATION_ESCAPE_CHAR		    0x05
#define LOCATION_MAX_ESCAPE_CHAR	  0x06
#define LOCATION_VERBOSE            0x07
#define LOCATION_ECHO               0x08
#define LOCATION_BAUD_SETTING_HIGH	0x09
#define LOCATION_BAUD_SETTING_MID	  0x0A
#define LOCATION_BAUD_SETTING_LOW	  0x0B
#define LOCATION_IGNORE_RX		      0x0C

#define BAUD_MIN  300
#define BAUD_MAX  1000000

#define MODE_NEWLOG	    0
#define MODE_SEQLOG     1
#define MODE_COMMAND    2

const byte stat1 = 5;  //This is the normal status LED
const byte stat2 = 13; //This is the SPI LED, indicating SD traffic

//Blinking LED error codes
#define ERROR_SD_INIT	    3
#define ERROR_NEW_BAUD	  5
#define ERROR_CARD_INIT   6
#define ERROR_VOLUME_INIT 7
#define ERROR_ROOT_INIT   8
#define ERROR_FILE_OPEN   9

#if !DEBUG
// Using OpenLog in an embedded environment only if not in debug mode. The reason for this
// is that we are out of space if the simple embedded is included
#define INCLUDE_SIMPLE_EMBEDDED
#endif

#ifdef INCLUDE_SIMPLE_EMBEDDED
#define EMBEDDED_END_MARKER  0x08
#endif

//These are bit locations used when testing for simple embedded commands.
#define ECHO			      0x01
#define EXTENDED_INFO		0x02
#define OFF  0x00
#define ON   0x01

SdFat sd;

long setting_uart_speed; //This is the baud rate that the system runs at, default is 9600. Can be 1,200 to 1,000,000
byte setting_systemMode; //This is the mode the system runs in, default is MODE_NEWLOG
byte setting_escape_character; //This is the ASCII character we look for to break logging, default is ctrl+z
byte setting_max_escape_character; //Number of escape chars before break logging, default is 3
byte setting_verbose; //This controls the whether we get extended or simple responses.
byte setting_echo; //This turns on/off echoing at the command prompt
byte setting_ignore_RX; //This flag, when set to 1 will make OpenLog ignore the state of the RX pin when powering up

//The number of command line arguments
//Increase to support more arguments but be aware of the memory restrictions
//command <arg1> <arg2> <arg3> <arg4> <arg5>
#define MAX_COUNT_COMMAND_LINE_ARGS 5

//Used for wild card delete and search
struct commandArg
{
  char* arg; //Points to first character in command line argument
  byte arg_length; //Length of command line argument
};
static struct commandArg cmd_arg[MAX_COUNT_COMMAND_LINE_ARGS];

byte feedbackMode = (ECHO | EXTENDED_INFO);

//Handle errors by printing the error type and blinking LEDs in certain way
//The function will never exit - it loops forever inside blinkError
void systemError(byte errorType)
{
  NewSerial.print(F("Error "));
  switch (errorType)
  {
    case ERROR_CARD_INIT:
      NewSerial.print(F("card.init"));
      blinkError(ERROR_SD_INIT);
      break;
    case ERROR_VOLUME_INIT:
      NewSerial.print(F("volume.init"));
      blinkError(ERROR_SD_INIT);
      break;
    case ERROR_ROOT_INIT:
      NewSerial.print(F("root.init"));
      blinkError(ERROR_SD_INIT);
      break;
    case ERROR_FILE_OPEN:
      NewSerial.print(F("file.open"));
      blinkError(ERROR_SD_INIT);
      break;
  }
}

void setup(void)
{
  pinMode(stat1, OUTPUT);

  //Power down various bits of hardware to lower power usage
  set_sleep_mode(SLEEP_MODE_IDLE);
  sleep_enable();

  //Shut off TWI, Timer2, Timer1, ADC
  ADCSRA &= ~(1 << ADEN); //Disable ADC
  ACSR = (1 << ACD); //Disable the analog comparator
  DIDR0 = 0x3F; //Disable digital input buffers on all ADC0-ADC5 pins
  DIDR1 = (1 << AIN1D) | (1 << AIN0D); //Disable digital input buffer on AIN1/0

  power_twi_disable();
  power_timer1_disable();
  power_timer2_disable();
  power_adc_disable();

  readSystemSettings(); //Load all system settings from EEPROM

  //Setup UART
  NewSerial.begin(setting_uart_speed);
  if (setting_uart_speed < 500)      // check for slow baud rates
  {
    //There is an error in the Serial library for lower than 500bps.
    //This fixes it. See issue 163: https://github.com/sparkfun/OpenLog/issues/163
    // redo USART baud rate configuration
    UBRR0 = (F_CPU / (16UL * setting_uart_speed)) - 1;
    UCSR0A &= ~_BV(U2X0);
  }
  NewSerial.print(F("1"));

  //Setup SD & FAT
  if (!sd.begin(SD_CHIP_SELECT, SPI_FULL_SPEED)) systemError(ERROR_CARD_INIT);
  if (!sd.chdir()) systemError(ERROR_ROOT_INIT); //Change to root directory. All new file creation will be in root.

  NewSerial.print(F("2"));

  //Search for a config file and load any settings found. This will over-ride previous EEPROM settings if found.
  readConfigFile();

  if (setting_ignore_RX == OFF) //If we are NOT ignoring RX, then
    checkEmergencyReset(); //Look to see if the RX pin is being pulled low

#if DEBUG
  NewSerial.print(F("FreeStack: "));
  NewSerial.println(FreeStack());
#endif

}

void loop(void)
{
  //If we are in new log mode, find a new file name to write to
  if (setting_systemMode == MODE_NEWLOG)
    appendFile(newLog()); //Append the file name that newLog() returns

  //If we are in sequential log mode, determine if seqLog.txt has been created or not, and then open it for logging
  if (setting_systemMode == MODE_SEQLOG)
    seqLog();

  //Once either one of these modes exits, go to normal command mode, which is called by returning to main()
  commandShell();
}

//Log to a new file everytime the system boots
//Checks the spots in EEPROM for the next available LOG# file name
//Updates EEPROM and then appends to the new log file.
//Limited to 65535 files but this should not always be the case.
char* newLog(void)
{
  byte msb, lsb;
  unsigned int newFileNumber;

  SdFile newFile; //This will contain the file for SD writing

  //Combine two 8-bit EEPROM spots into one 16-bit number
  lsb = EEPROM.read(LOCATION_FILE_NUMBER_LSB);
  msb = EEPROM.read(LOCATION_FILE_NUMBER_MSB);

  newFileNumber = msb;
  newFileNumber = newFileNumber << 8;
  newFileNumber |= lsb;

  //If both EEPROM spots are 255 (0xFF), that means they are un-initialized (first time OpenLog has been turned on)
  //Let's init them both to 0
  if ((lsb == 255) && (msb == 255))
  {
    newFileNumber = 0; //By default, unit will start at file number zero
    EEPROM.write(LOCATION_FILE_NUMBER_LSB, 0x00);
    EEPROM.write(LOCATION_FILE_NUMBER_MSB, 0x00);
  }

  //The above code looks like it will forever loop if we ever create 65535 logs
  //Let's quit if we ever get to 65534
  //65534 logs is quite possible if you have a system with lots of power on/off cycles
  if (newFileNumber == 65534)
  {
    //Gracefully drop out to command prompt with some error
    NewSerial.print(F("!Too many logs:1!"));
    return (0); //Bail!
  }

  //If we made it this far, everything looks good - let's start testing to see if our file number is the next available
#if DEBUG
  NewSerial.print(F("Found file number: "));
  NewSerial.println(newFileNumber);
#endif

  //There is a weird EEPROM power-up glitch that causes the newFileNumber to advance
  //arbitrarily. This fixes that problem.
  if(newFileNumber > 0) newFileNumber--;

  //Search for next available log spot
  static char newFileName[13]; //Bug fix from ystark's pull request: https://github.com/sparkfun/OpenLog/pull/189
  while (1)
  {
    sprintf_P(newFileName, PSTR("LOG%05u.TXT"), newFileNumber); //Splice the new file number into this file name

    // O_CREAT - create the file if it does not exist
    // O_APPEND - seek to the end of the file prior to each write
    // O_WRITE - open for write
    // O_EXCL - if O_CREAT and O_EXCEL are set, open() shall fail if file exists 

    //Try to open file, if it opens (file doesn't exist), then break
    if (newFile.open(newFileName, O_CREAT | O_EXCL | O_WRITE)) break;

    //Try to open file and see if it is empty. If so, use it.
    if (newFile.open(newFileName, O_READ))
    {
      if (newFile.fileSize() == 0)
      {
        newFile.close();        // Close this existing file we just opened.
        return (newFileName); // Use existing empty file.
      }
      newFile.close(); // Close this existing file we just opened.
    }

    //Try the next number
    newFileNumber++;
    if (newFileNumber > 65533) //There is a max of 65534 logs
    {
      NewSerial.print(F("!Too many logs:2!"));
      return (0); //Bail!
    }
  }
  newFile.close(); //Close this new file we just opened

  newFileNumber++; //Increment so the next power up uses the next file #

  //Record new_file number to EEPROM
  lsb = (byte)(newFileNumber & 0x00FF);
  msb = (byte)((newFileNumber & 0xFF00) >> 8);

  EEPROM.write(LOCATION_FILE_NUMBER_LSB, lsb); // LSB

  if (EEPROM.read(LOCATION_FILE_NUMBER_MSB) != msb)
    EEPROM.write(LOCATION_FILE_NUMBER_MSB, msb); // MSB

#if DEBUG
  NewSerial.print(F("Stored file number: "));
  NewSerial.println(newFileNumber);

  NewSerial.print(F("Created new file: "));
  NewSerial.println(newFileName);
#endif

  return (newFileName);
}

//Log to the same file every time the system boots, sequentially
//Checks to see if the file SEQLOG.txt is available
//If not, create it
//If yes, append to it
//Return 0 on error
//Return anything else on success
void seqLog(void)
{
  SdFile seqFile;

  char sequentialFileName[strlen(SEQ_FILENAME)]; //Limited to 8.3
  strcpy_P(sequentialFileName, PSTR(SEQ_FILENAME)); //This is the name of the config file. 'config.sys' is probably a bad idea.

  //Try to create sequential file
  if (!seqFile.open(sequentialFileName, O_CREAT | O_WRITE))
  {
    NewSerial.println(F("Error creating SEQLOG"));
    return;
  }

  seqFile.close(); //Close this new file we just opened

  appendFile(sequentialFileName);
}

//This is the most important function of the device. These loops have been tweaked as much as possible.
//Modifying this loop may negatively affect how well the device can record at high baud rates.
//Appends a stream of serial data to a given file
//Does not exit until escape character is received the correct number of times
//Returns 0 on error
//Returns 1 on success
byte appendFile(char* fileName)
{
  SdFile workingFile;

  // O_CREAT - create the file if it does not exist
  // O_APPEND - seek to the end of the file prior to each write
  // O_WRITE - open for write
  if (!workingFile.open(fileName, O_CREAT | O_APPEND | O_WRITE)) systemError(ERROR_FILE_OPEN);

  if (workingFile.fileSize() == 0) {
    //This is a trick to make sure first cluster is allocated - found in Bill's example/beta code
    workingFile.rewind();
    workingFile.sync();
  }

  //This is the 2nd buffer. It pulls from the larger Serial buffer as quickly as possible.
  //The built-in Arduino serial buffer is 64 bytes: https://www.arduino.cc/en/Serial/Available
  byte localBuffer[LOCAL_BUFF_SIZE];

  byte checkedSpot;
  byte escapeCharsReceived = 0;

  const unsigned int MAX_IDLE_TIME_MSEC = 500; //The number of milliseconds before unit goes to sleep
  unsigned long lastSyncTime = millis(); //Keeps track of the last time the file was synced

#if DEBUG
  NewSerial.print(F("FreeStack: "));
  NewSerial.println(FreeStack());
#endif

  NewSerial.print(F("<")); //give a different prompt to indicate no echoing
  digitalWrite(stat1, HIGH); //Turn on indicator LED

  //Check if we should ignore escape characters
  //If we are ignoring escape characters the recording loop is infinite and can be made shorter (less checking)
  //This should allow for recording at higher incoming rates
  if (setting_max_escape_character == 0)
  {
    //Start recording incoming characters
    //With no escape characters, do this infinitely
    while (1)
    {
      byte charsToRecord = NewSerial.read(localBuffer, sizeof(localBuffer)); //Read characters from global buffer into the local buffer
      if (charsToRecord > 0) //If we have characters, check for escape characters
      {
        workingFile.write(localBuffer, charsToRecord); //Record the buffer to the card

        toggleLED(stat1); //Toggle the STAT1 LED each time we record the buffer
      }
      //No characters received?
      else if ( (millis() - lastSyncTime) > MAX_IDLE_TIME_MSEC) //If we haven't received any characters in 2s, goto sleep
      {
        workingFile.sync(); //Sync the card before we go to sleep

        digitalWrite(stat1, LOW); //Turn off stat LED to save power

        power_timer0_disable(); //Shut down peripherals we don't need
        power_spi_disable();
        sleep_mode(); //Stop everything and go to sleep. Wake up if serial character received

        power_spi_enable(); //After wake up, power up peripherals
        power_timer0_enable();

        escapeCharsReceived = 0; // Clear the esc flag as it has timed out
        lastSyncTime = millis(); //Reset the last sync time to now
      }
    }
  }

  //We only get this far if escape characters are more than zero

  //Start recording incoming characters
  while (escapeCharsReceived < setting_max_escape_character)
  {
    byte charsToRecord = NewSerial.read(localBuffer, sizeof(localBuffer)); //Read characters from global buffer into the local buffer
    if (charsToRecord > 0) //If we have characters, check for escape characters
    {
      if (localBuffer[0] == setting_escape_character)
      {
        escapeCharsReceived++;

        //Scan the local buffer for esacape characters
        for (checkedSpot = 1 ; checkedSpot < charsToRecord ; checkedSpot++)
        {
          if (localBuffer[checkedSpot] == setting_escape_character) {
            escapeCharsReceived++;
            //If charsToRecord is greater than 3 there's a chance here where we receive three esc chars
            // and then reset the variable: 26 26 26 A T + would not escape correctly
            if (escapeCharsReceived == setting_max_escape_character) break;
          }
          else
            escapeCharsReceived = 0;
        }
      }
      else
        escapeCharsReceived = 0;

      workingFile.write(localBuffer, charsToRecord); //Record the buffer to the card

      toggleLED(stat1); //Toggle the STAT1 LED each time we record the buffer
    }
    //No characters recevied?
    else if ( (millis() - lastSyncTime) > MAX_IDLE_TIME_MSEC) //If we haven't received any characters in 2s, goto sleep
    {
      workingFile.sync(); //Sync the card before we go to sleep

      digitalWrite(stat1, LOW); //Turn off stat LED to save power

      power_timer0_disable(); //Shut down peripherals we don't need
      power_spi_disable();
      sleep_mode(); //Stop everything and go to sleep. Wake up if serial character received

      power_spi_enable(); //After wake up, power up peripherals
      power_timer0_enable();

      escapeCharsReceived = 0; // Clear the esc flag as it has timed out
      lastSyncTime = millis(); //Reset the last sync time to now
    }

  }

  workingFile.sync();

  //Remove the escape characters from the end of the file
  if(setting_max_escape_character > 0) 
    workingFile.truncate(workingFile.fileSize() - setting_max_escape_character);
  
  workingFile.close(); // Done recording, close out the file

  digitalWrite(stat1, LOW); // Turn off indicator LED

  NewSerial.print(F("~")); // Indicate a successful record

  return (1); //Success!
}

//The following are system functions needed for basic operation
//=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=

//Blinks the status LEDs to indicate a type of error
void blinkError(byte ERROR_TYPE) {
  while (1) {
    for (int x = 0 ; x < ERROR_TYPE ; x++) {
      digitalWrite(stat1, HIGH);
      delay(200);
      digitalWrite(stat1, LOW);
      delay(200);
    }

    delay(2000);
  }
}

//Check to see if we need an emergency UART reset
//Scan the RX pin for 2 seconds
//If it's low the entire time, then return 1
void checkEmergencyReset(void)
{
  pinMode(0, INPUT); //Turn the RX pin into an input
  digitalWrite(0, HIGH); //Push a 1 onto RX pin to enable internal pull-up

  //Quick pin check
  if (digitalRead(0) == HIGH) return;

  //Disable SPI so that we control the LEDs
  SPI.end();

  //Wait 2 seconds, blinking LEDs while we wait
  pinMode(stat2, OUTPUT);
  digitalWrite(stat2, HIGH); //Set the STAT2 LED
  for (byte i = 0 ; i < 40 ; i++)
  {
    delay(25);
    toggleLED(stat1); //Blink the stat LEDs

    if (digitalRead(0) == HIGH) return; //Check to see if RX is not low anymore

    delay(25);
    toggleLED(stat2); //Blink the stat LEDs

    if (digitalRead(0) == HIGH) return; //Check to see if RX is not low anymore
  }

  //If we make it here, then RX pin stayed low the whole time
  setDefaultSettings(); //Reset baud, escape characters, escape number, system mode

  //Try to setup the SD card so we can record these new settings
  if (!sd.begin(SD_CHIP_SELECT, SPI_HALF_SPEED)) systemError(ERROR_CARD_INIT);
  if (!sd.chdir()) systemError(ERROR_ROOT_INIT); //Change to root directory

  recordConfigFile(); //Record new config settings

  //Disable SPI so that we control the LEDs
  SPI.end();

  pinMode(stat1, OUTPUT);
  pinMode(stat2, OUTPUT);
  digitalWrite(stat1, HIGH);
  digitalWrite(stat2, HIGH);

  //Now sit in forever loop indicating system is now at 9600bps
  while (1)
  {
    delay(500);
    toggleLED(stat1); //Blink the stat LEDs
    toggleLED(stat2); //Blink the stat LEDs
  }
}

//Resets all the system settings to safe values
void setDefaultSettings(void)
{
  //Reset UART to 9600bps
  writeBaud(9600);

  //Reset system to new log mode
  EEPROM.write(LOCATION_SYSTEM_SETTING, MODE_NEWLOG);

  //Reset escape character to ctrl+z
  EEPROM.write(LOCATION_ESCAPE_CHAR, 26);

  //Reset number of escape characters to 3
  EEPROM.write(LOCATION_MAX_ESCAPE_CHAR, 3);

  //Reset verbose responses to on
  EEPROM.write(LOCATION_VERBOSE, ON);

  //Reset echo to on
  EEPROM.write(LOCATION_ECHO, ON);

  //Reset the ignore RX to 'Pay attention to RX!'
  EEPROM.write(LOCATION_IGNORE_RX, OFF);

  //These settings are not recorded to the config file
  //We can't do it here because we are not sure the FAT system is init'd
}

//Reads the current system settings from EEPROM
//If anything looks weird, reset setting to default value
void readSystemSettings(void)
{
  //Read what the current UART speed is from EEPROM memory
  //Default is 9600
  setting_uart_speed = readBaud(); //Combine the three bytes
  if (setting_uart_speed < BAUD_MIN || setting_uart_speed > BAUD_MAX)
  {
    setting_uart_speed = 9600; //Reset UART to 9600 if there is no speed stored
    writeBaud(setting_uart_speed); //Record to EEPROM
  }

  //Determine the system mode we should be in
  //Default is NEWLOG mode
  setting_systemMode = EEPROM.read(LOCATION_SYSTEM_SETTING);
  if (setting_systemMode > 5)
  {
    setting_systemMode = MODE_NEWLOG; //By default, unit will turn on and go to new file logging
    EEPROM.write(LOCATION_SYSTEM_SETTING, setting_systemMode);
  }

  //Read the escape_character
  //ASCII(26) is ctrl+z
  setting_escape_character = EEPROM.read(LOCATION_ESCAPE_CHAR);
  if (setting_escape_character == 0 || setting_escape_character == 255)
  {
    setting_escape_character = 26; //Reset escape character to ctrl+z
    EEPROM.write(LOCATION_ESCAPE_CHAR, setting_escape_character);
  }

  //Read the number of escape_characters to look for
  //Default is 3
  setting_max_escape_character = EEPROM.read(LOCATION_MAX_ESCAPE_CHAR);
  if (setting_max_escape_character == 255)
  {
    setting_max_escape_character = 3; //Reset number of escape characters to 3
    EEPROM.write(LOCATION_MAX_ESCAPE_CHAR, setting_max_escape_character);
  }

  //Read whether we should use verbose responses or not
  //Default is true
  setting_verbose = EEPROM.read(LOCATION_VERBOSE);
  if (setting_verbose != ON || setting_verbose != OFF)
  {
    setting_verbose = ON; //Reset verbose to true
    EEPROM.write(LOCATION_VERBOSE, setting_verbose);
  }

  //Read whether we should echo characters or not
  //Default is true
  setting_echo = EEPROM.read(LOCATION_ECHO);
  if (setting_echo != ON || setting_echo != OFF)
  {
    setting_echo = ON; //Reset to echo on
    EEPROM.write(LOCATION_ECHO, setting_echo);
  }

  //Set flags for extended mode options
  if (setting_verbose == ON)
    feedbackMode |= EXTENDED_INFO;
  else
    feedbackMode &= ((byte)~EXTENDED_INFO);

  if (setting_echo == ON)
    feedbackMode |= ECHO;
  else
    feedbackMode &= ((byte)~ECHO);

  //Read whether we should ignore RX at power up
  //Some users need OpenLog to ignore the RX pin during power up
  //Default is false or ignore
  setting_ignore_RX = EEPROM.read(LOCATION_IGNORE_RX);
  if (setting_ignore_RX > 1)
  {
    setting_ignore_RX = OFF; //By default we DO NOT ignore RX
    EEPROM.write(LOCATION_IGNORE_RX, setting_ignore_RX);
  }
}

void readConfigFile(void)
{
  SdFile configFile;

  if (!sd.chdir()) systemError(ERROR_ROOT_INIT); // open the root directory

  char configFileName[strlen(CFG_FILENAME)]; //Limited to 8.3
  strcpy_P(configFileName, PSTR(CFG_FILENAME)); //This is the name of the config file. 'config.sys' is probably a bad idea.

  //Check to see if we have a config file
  if (!configFile.open(configFileName, O_READ))
  {
    //If we don't have a config file already, then create config file and record the current system settings to the file
#if DEBUG
    NewSerial.println(F("No config found - creating default:"));
#endif
    configFile.close();

    //Record the current eeprom settings to the config file
    recordConfigFile();
    return;
  }

  //If we found the config file then load settings from file and push them into EEPROM
#if DEBUG
  NewSerial.println(F("Found config file!"));
#endif

  //Read up to 22 characters from the file. There may be a better way of doing this...
  char c;
  int len;
  byte settingsString[CFG_LENGTH]; //"115200,103,14,0,1,1,0\r" = 115200 bps, escape char of ASCII(103), 14 times, new log mode, verbose on, echo on, ignore RX false.
  for (len = 0 ; len < CFG_LENGTH ; len++) {
    c = configFile.read();
    if (!(c == ',' || (c >= '0' && c <= '9'))) break; //Bail if we hit a non-numeric or non-comma character
    settingsString[len] = c;
  }

  configFile.close();

#if DEBUG
  //Print line for debugging
  NewSerial.print(F("Text Settings: "));
  for (int i = 0; i < len; i++)
    NewSerial.write(settingsString[i]);
  NewSerial.println();
  NewSerial.print(F("Len: "));
  NewSerial.println(len);
#endif

  //Default the system settings in case things go horribly wrong
  long new_system_baud = 9600;
  byte new_systemMode = MODE_NEWLOG;
  byte new_system_escape = 26;
  byte new_system_max_escape = 3;
  byte new_system_verbose = ON;
  byte new_system_echo = ON;
  byte new_system_ignore_RX = OFF;

  //Parse the settings out
  byte i = 0, j = 0, settingNumber = 0;
  char newSettingString[8]; //Max length of a setting is 7, the bps setting = '1000000' plus '\0'
  byte newSettingInt = 0;

  for (i = 0 ; i < len; i++)
  {
    //Pick out one setting from the line of text
    for (j = 0 ; settingsString[i] != ',' && i < len && j < 7 ; )
    {
      newSettingString[j] = settingsString[i];
      i++;
      j++;
    }

    newSettingString[j] = '\0'; //Terminate the string for array compare
    newSettingInt = atoi(newSettingString); //Convert string to int

    if (settingNumber == 0) //Baud rate
    {
      new_system_baud = strToLong(newSettingString);

      //Basic error checking
      if (new_system_baud < BAUD_MIN || new_system_baud > BAUD_MAX) new_system_baud = 9600; //Default to 9600
    }
    else if (settingNumber == 1) //Escape character
    {
      new_system_escape = newSettingInt;
      if (new_system_escape == 0 || new_system_escape > 127) new_system_escape = 26; //Default is ctrl+z
    }
    else if (settingNumber == 2) //Max amount escape character
    {
      new_system_max_escape = newSettingInt;
      if (new_system_max_escape > 254) new_system_max_escape = 3; //Default is 3
    }
    else if (settingNumber == 3) //System mode
    {
      new_systemMode = newSettingInt;
      if (new_systemMode == 0 || new_systemMode > MODE_COMMAND) new_systemMode = MODE_NEWLOG; //Default is NEWLOG
    }
    else if (settingNumber == 4) //Verbose setting
    {
      new_system_verbose = newSettingInt;
      if (new_system_verbose != ON && new_system_verbose != OFF) new_system_verbose = ON; //Default is on
    }
    else if (settingNumber == 5) //Echo setting
    {
      new_system_echo = newSettingInt;
      if (new_system_echo != ON && new_system_echo != OFF) new_system_echo = ON; //Default is on
    }
    else if (settingNumber == 6) //Ignore RX setting
    {
      new_system_ignore_RX = newSettingInt;
      if (new_system_ignore_RX != ON && new_system_ignore_RX != OFF) new_system_ignore_RX = OFF; //Default is to listen to RX
    }
    else
      //We're done! Stop looking for settings
      break;

    settingNumber++;
  }

  //We now have the settings loaded into the global variables. Now check if they're different from EEPROM settings
  boolean recordNewSettings = false;

  if (new_system_baud != setting_uart_speed) {
    //If the baud rate from the file is different from the current setting,
    //Then update the setting to the file setting
    //And re-init the UART

    writeBaud(new_system_baud); //Write this baudrate to EEPROM
    setting_uart_speed = new_system_baud;
    NewSerial.begin(setting_uart_speed); //Move system to new uart speed

    recordNewSettings = true;
  }

  if (new_systemMode != setting_systemMode) {
    //Goto new system mode
    setting_systemMode = new_systemMode;
    EEPROM.write(LOCATION_SYSTEM_SETTING, setting_systemMode);

    recordNewSettings = true;
  }

  if (new_system_escape != setting_escape_character) {
    //Goto new system escape char
    setting_escape_character = new_system_escape;
    EEPROM.write(LOCATION_ESCAPE_CHAR, setting_escape_character);

    recordNewSettings = true;
  }

  if (new_system_max_escape != setting_max_escape_character) {
    //Goto new max escape
    setting_max_escape_character = new_system_max_escape;
    EEPROM.write(LOCATION_MAX_ESCAPE_CHAR, setting_max_escape_character);

    recordNewSettings = true;
  }

  if (new_system_verbose != setting_verbose) {
    //Goto new verbose setting
    setting_verbose = new_system_verbose;
    EEPROM.write(LOCATION_VERBOSE, setting_verbose);

    recordNewSettings = true;
  }

  if (new_system_echo != setting_echo) {
    //Goto new echo setting
    setting_echo = new_system_echo;
    EEPROM.write(LOCATION_ECHO, setting_echo);

    recordNewSettings = true;
  }

  if (new_system_ignore_RX != setting_ignore_RX) {
    //Goto new ignore setting
    setting_ignore_RX = new_system_ignore_RX;
    EEPROM.write(LOCATION_IGNORE_RX, setting_ignore_RX);

    recordNewSettings = true;
  }

  //We don't want to constantly record a new config file on each power on. Only record when there is a change.
  if (recordNewSettings == true)
    recordConfigFile(); //If we corrected some values because the config file was corrupt, then overwrite any corruption
#if DEBUG
  else
    NewSerial.println(F("Config file matches system settings"));
#endif

  //All done! New settings are loaded. System will now operate off new config settings found in file.

  //Set flags for extended mode options
  if (setting_verbose == ON)
    feedbackMode |= EXTENDED_INFO;
  else
    feedbackMode &= ((byte)~EXTENDED_INFO);

  if (setting_echo == ON)
    feedbackMode |= ECHO;
  else
    feedbackMode &= ((byte)~ECHO);

}

//Records the current EEPROM settings to the config file
//If a config file exists, it is trashed and a new one is created
void recordConfigFile(void)
{
  SdFile myFile;

  if (!sd.chdir()) systemError(ERROR_ROOT_INIT); // open the root directory

  char configFileName[strlen(CFG_FILENAME)];
  strcpy_P(configFileName, PSTR(CFG_FILENAME)); //This is the name of the config file. 'config.sys' is probably a bad idea.

  //If there is currently a config file, trash it
  if (myFile.open(configFileName, O_WRITE)) {
    if (!myFile.remove()) {
      NewSerial.println(F("Remove config failed"));
      myFile.close(); //Close this file
      return;
    }
  }

  //myFile.close(); //Not sure if we need to close the file before we try to reopen it

  //Create config file
  myFile.open(configFileName, O_CREAT | O_APPEND | O_WRITE);

  //Config was successfully created, now record current system settings to the config file

  char settingsString[CFG_LENGTH]; //"115200,103,14,0,1,1,0\0" = 115200 bps, escape char of ASCII(103), 14 times, new log mode, verbose on, echo on, ignore RX false.

  //Before we read the EEPROM values, they've already been tested and defaulted in the readSystemSettings function
  long current_system_baud = readBaud();
  byte current_system_escape = EEPROM.read(LOCATION_ESCAPE_CHAR);
  byte current_system_max_escape = EEPROM.read(LOCATION_MAX_ESCAPE_CHAR);
  byte current_systemMode = EEPROM.read(LOCATION_SYSTEM_SETTING);
  byte current_system_verbose = EEPROM.read(LOCATION_VERBOSE);
  byte current_system_echo = EEPROM.read(LOCATION_ECHO);
  byte current_system_ignore_RX = EEPROM.read(LOCATION_IGNORE_RX);

  //Convert system settings to visible ASCII characters
  sprintf_P(settingsString, PSTR("%ld,%d,%d,%d,%d,%d,%d\0"), current_system_baud, current_system_escape, current_system_max_escape, current_systemMode, current_system_verbose, current_system_echo, current_system_ignore_RX);

  //Record current system settings to the config file
  myFile.write(settingsString, strlen(settingsString));

  myFile.println(); //Add a break between lines

  //Add a decoder line to the file
#define HELP_STR "baud,escape,esc#,mode,verb,echo,ignoreRX\0"
  char helperString[strlen(HELP_STR) + 1]; //strlen is preprocessed but returns one less because it ignores the \0
  strcpy_P(helperString, PSTR(HELP_STR));
  myFile.write(helperString); //Add this string to the file

  myFile.sync(); //Sync all newly written data to card
  myFile.close(); //Close this file
  //Now that the new config file has the current system settings, nothing else to do!
}

//Given a baud rate (long number = four bytes but we only use three), record to EEPROM
void writeBaud(long uartRate)
{
  EEPROM.write(LOCATION_BAUD_SETTING_HIGH, (byte)((uartRate & 0x00FF0000) >> 16));
  EEPROM.write(LOCATION_BAUD_SETTING_MID, (byte)(uartRate >> 8));
  EEPROM.write(LOCATION_BAUD_SETTING_LOW, (byte)uartRate);
}

//Look up the baud rate. This requires three bytes be combined into one long
long readBaud(void)
{
  byte uartSpeedHigh = EEPROM.read(LOCATION_BAUD_SETTING_HIGH);
  byte uartSpeedMid = EEPROM.read(LOCATION_BAUD_SETTING_MID);
  byte uartSpeedLow = EEPROM.read(LOCATION_BAUD_SETTING_LOW);

  long uartSpeed = 0x00FF0000 & ((long)uartSpeedHigh << 16) | ((long)uartSpeedMid << 8) | uartSpeedLow; //Combine the three bytes

  return (uartSpeed);
}


//End core system functions
//=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=


void commandShell(void)
{
  SdFile tempFile;
  sd.chdir("/", true); //Change to root directory

  char buffer[30];
  byte tempVar;

  char parentDirectory[13]; //This tracks the current parent directory. Limited to 13 characters.

#if DEBUG
  NewSerial.print(F("FreeStack: "));
  NewSerial.println(FreeStack());
#endif

#ifdef INCLUDE_SIMPLE_EMBEDDED
  uint32_t file_index;
  byte commandSucceeded = 1;
#endif //INCLUDE_SIMPLE_EMBEDDED

  while (true)
  {
#ifdef INCLUDE_SIMPLE_EMBEDDED
    if ((feedbackMode & EMBEDDED_END_MARKER) > 0)
      NewSerial.print((char)0x1A); // Ctrl+Z ends the data and marks the start of result

    if (commandSucceeded == 0)
      NewSerial.print(F("!"));
#endif
    NewSerial.print(F(">"));

    //Read command
    if (readLine(buffer, sizeof(buffer)) < 1)
    {
#ifdef INCLUDE_SIMPLE_EMBEDDED
      commandSucceeded = 1;
#endif
      continue;
    }

#ifdef INCLUDE_SIMPLE_EMBEDDED
    commandSucceeded = 0;
#endif

    //Argument 1: The actual command
    char* commandArg = getCmdArg(0);

    //Execute command
    if (strcmp_P(commandArg, PSTR("init")) == 0)
    {
      if ((feedbackMode & EXTENDED_INFO) > 0)
        NewSerial.println(F("Closing down file system"));

      if (!sd.begin(SD_CHIP_SELECT, SPI_FULL_SPEED)) systemError(ERROR_CARD_INIT);
      if (!sd.chdir()) systemError(ERROR_ROOT_INIT); //Change to root directory

      if ((feedbackMode & EXTENDED_INFO) > 0)
        NewSerial.println(F("File system initialized"));
#ifdef INCLUDE_SIMPLE_EMBEDDED
      commandSucceeded = 1;
#endif
    }

    else if (strcmp_P(commandArg, PSTR("?")) == 0)
    {
      //Print available commands
      printMenu();

#ifdef INCLUDE_SIMPLE_EMBEDDED
      commandSucceeded = 1;
#endif

    }
    else if (strcmp_P(commandArg, PSTR("help")) == 0)
    {
      //Print available commands
      printMenu();

#ifdef INCLUDE_SIMPLE_EMBEDDED
      commandSucceeded = 1;
#endif

    }
    else if (strcmp_P(commandArg, PSTR("baud")) == 0)
    {
      //Go into baud select menu
      baudMenu();

#ifdef INCLUDE_SIMPLE_EMBEDDED
      commandSucceeded = 1;
#endif

    }
    else if (strcmp_P(commandArg, PSTR("set")) == 0)
    {
      //Go into system setting menu
      systemMenu();

#ifdef INCLUDE_SIMPLE_EMBEDDED
      commandSucceeded = 1;
#endif
    }

    else if (strcmp_P(commandArg, PSTR("ls")) == 0)
    {
      if ((feedbackMode & EXTENDED_INFO) > 0)
      {
        NewSerial.print(F("Volume is FAT"));
        NewSerial.println(sd.vol()->fatType(), DEC);
      }

      if (countCmdArgs() == 1)  // has no arguments
      {
        // Don't use the 'ls()' method in the SdFat library as it does not
        // limit recursion into subdirectories.
        commandArg[0] = '*';       // use global wildcard
        commandArg[1] = '\0';
      }
      else      // has argument (and possible wildcards)
      {
        commandArg = getCmdArg(1);
        strupr(commandArg); //Convert to uppercase
      }

      // display listing with limited recursion into subdirectories
      lsPrint(sd.vwd(), commandArg, LS_SIZE | LS_R, 0);

#ifdef INCLUDE_SIMPLE_EMBEDDED
      commandSucceeded = 1;
#endif

    }
    else if (strcmp_P(commandArg, PSTR("md")) == 0)
    {
      //Argument 2: Directory name
      commandArg = getCmdArg(1);
      if (commandArg == 0)
        continue;

      if (!sd.mkdir(commandArg)) { //Make a directory in our current folder
        if ((feedbackMode & EXTENDED_INFO) > 0)
        {
          NewSerial.print(F("Error creating directory: "));
          NewSerial.println(commandArg);
        }
      }
#ifdef INCLUDE_SIMPLE_EMBEDDED
      else
      {
        commandSucceeded = 1;
      }
#endif

    }
    //NOTE on using "rm <option>/<file> <subfolder>"
    // "rm -rf <subfolder>" removes the <subfolder> and all contents recursively
    // "rm <subfolder>" removes the <subfolder> only if its empty
    // "rm <filename>" removes the <filename>
    else if (strcmp_P(commandArg, PSTR("rm")) == 0)
    {
      //Argument 2: Remove option or file name/subdirectory to remove
      commandArg = getCmdArg(1);
      if (commandArg == 0)
        continue;

      //Argument 2: Remove subfolder recursively?
      if ((countCmdArgs() == 3) && (strcmp_P(commandArg, PSTR("-rf")) == 0))
      {
        //Remove the subfolder
        if (tempFile.open(sd.vwd(), getCmdArg(2), O_READ))
        {
          tempVar = tempFile.rmRfStar();
          tempFile.close();
#ifdef INCLUDE_SIMPLE_EMBEDDED
          commandSucceeded = tempVar;
#endif
        }
        continue;
      }

      //Argument 2: Remove subfolder if empty or remove file
      if (tempFile.open(sd.vwd(), commandArg, O_READ))
      {
        tempVar = 0;
        if (tempFile.isDir() || tempFile.isSubDir())
          tempVar = tempFile.rmdir();
        else
        {
          tempFile.close();
          if (tempFile.open(commandArg, O_WRITE))
            tempVar = tempFile.remove();
        }
#ifdef INCLUDE_SIMPLE_EMBEDDED
        commandSucceeded = tempVar;
#endif
        tempFile.close();
        continue;
      }

      //Argument 2: File wildcard removal
      //Fixed by dlkeng - Thank you!
      uint32_t filesDeleted = 0;

      char fname[13]; //Used to store the file and directory names as we step through this directory

      strupr(commandArg);

      sd.chdir("/"); //TODO this is required for some reason - putting at top of function doesn't work
      while (tempFile.openNext(sd.vwd(), O_READ)) //Step through each object in the current directory
      {
        if (tempFile.isFile()) // Remove only files
        {
          if (tempFile.getSFN(fname)) // Get the filename of the object we're looking at
          {
            if (wildcmp(commandArg, fname))  // See if it matches the wildcard
            {
              tempFile.close();
              tempFile.open(fname, O_WRITE);  // Re-open for WRITE to be deleted

              if (tempFile.remove()) // Remove this file
              {
                ++filesDeleted;
              }
            }
          }
        }
        tempFile.close();
      }

      if ((feedbackMode & EXTENDED_INFO) > 0)
      {
        NewSerial.print(filesDeleted);
        NewSerial.println(F(" file(s) deleted"));
      }
#ifdef INCLUDE_SIMPLE_EMBEDDED
      if (filesDeleted > 0)
        commandSucceeded = 1;
#endif
    }
    else if (strcmp_P(commandArg, PSTR("cd")) == 0)
    {
      //Argument 2: Directory name
      commandArg = getCmdArg(1);
      if (commandArg == 0)
        continue;

      if (strcmp_P(commandArg, PSTR("..")) == 0)
      {
        //User is trying to move up the directory tree. Move to root instead
        //TODO store the parent director name and change to that instead
        tempVar = sd.chdir("/"); //Change to root
      }
      else
      {
        //User is trying to change to a named subdirectory
        tempVar = sd.chdir(commandArg);
      }

#ifdef INCLUDE_SIMPLE_EMBEDDED
      commandSucceeded = tempVar;
#endif
    }
    else if (strcmp_P(commandArg, PSTR("read")) == 0)
    {
      //Argument 2: File name
      commandArg = getCmdArg(1);
      if (commandArg == 0)
        continue;

      //search file in current directory and open it
      if (!tempFile.open(commandArg, O_READ)) {
        if ((feedbackMode & EXTENDED_INFO) > 0)
        {
          NewSerial.print(F("Failed to open file "));
          NewSerial.println(commandArg);
        }
        continue;
      }

      //Argument 3: File seek position
      if ((commandArg = getCmdArg(2)) != 0) {
        if ((commandArg = isNumber(commandArg, strlen(commandArg))) != 0) {
          int32_t offset = strToLong(commandArg);
          if (!tempFile.seekSet(offset)) {
            if ((feedbackMode & EXTENDED_INFO) > 0)
            {
              NewSerial.print(F("Error seeking to "));
              NewSerial.println(commandArg);
            }
            tempFile.close();
            continue;
          }
        }
      }

      //Argument 4: How much data (number of characters) to read from file
      uint32_t readAmount = (uint32_t) - 1;
      if ((commandArg = getCmdArg(3)) != 0)
        if ((commandArg = isNumber(commandArg, strlen(commandArg))) != 0)
          readAmount = strToLong(commandArg);

      //Argument 5: Should we print ASCII or HEX? 1 = ASCII, 2 = HEX, 3 = RAW
      uint32_t printType = 1; //Default to ASCII
      if ((commandArg = getCmdArg(4)) != 0)
        if ((commandArg = isNumber(commandArg, strlen(commandArg))) != 0)
          printType = strToLong(commandArg);

      //Print file contents from current seek position to the end (readAmount)
      byte c;
      int16_t v;
      int16_t readSpot = 0;
      while ((v = tempFile.read()) >= 0) {
        //file.read() returns a 16 bit character. We want to be able to print extended ASCII
        //So we need 8 bit unsigned.
        c = v; //Force the 16bit signed variable into an 8bit unsigned

        if (++readSpot > readAmount) break;
        if (printType == 1) { //Printing ASCII
          //Test character to see if it is visible, if not print '.'
          if (c >= ' ' && c < 127)
            NewSerial.write(c); //Regular ASCII
          else if (c == '\n' || c == '\r')
            NewSerial.write(c); //Go ahead and print the carriage returns and new lines
          else
            NewSerial.print(F(".")); //For non visible ASCII characters, print a .
        }
        else if (printType == 2) {
          NewSerial.print(c, HEX); //Print in HEX
          NewSerial.print(F(" "));
        }
        else if (printType == 3) {
          NewSerial.write(c); //Print raw
        }

      }
      tempFile.close();
#ifdef INCLUDE_SIMPLE_EMBEDDED
      commandSucceeded = 1;
      if ((feedbackMode & EMBEDDED_END_MARKER) == 0)
#endif
        NewSerial.println();
    }
    else if (strcmp_P(commandArg, PSTR("write")) == 0)
    {
      //Argument 2: File name
      commandArg = getCmdArg(1);
      if (commandArg == 0)
        continue;

      //search file in current directory and open it
      if (!tempFile.open(commandArg, O_WRITE)) {
        if ((feedbackMode & EXTENDED_INFO) > 0)
        {
          NewSerial.print(F("Failed to open file "));
          NewSerial.println(commandArg);
        }
        continue;
      }

      //Argument 3: File seek position
      if ((commandArg = getCmdArg(2)) != 0) {
        if ((commandArg = isNumber(commandArg, strlen(commandArg))) != 0) {
          int32_t offset = strToLong(commandArg);
          if (!tempFile.seekSet(offset)) {
            if ((feedbackMode & EXTENDED_INFO) > 0)
            {
              NewSerial.print(F("Error seeking to "));
              NewSerial.println(commandArg);
            }
            tempFile.close();
            continue;
          }
        }
      }

      //read text from the shell and write it to the file
      byte dataLen;
      while (1) {
#ifdef INCLUDE_SIMPLE_EMBEDDED
        if ((feedbackMode & EMBEDDED_END_MARKER) > 0)
          NewSerial.print((char)0x1A); // Ctrl+Z ends the data and marks the start of result
#endif
        NewSerial.print(F("<")); //give a different prompt

        //read one line of text
        dataLen = readLine(buffer, sizeof(buffer));
        if (!dataLen) {
#ifdef INCLUDE_SIMPLE_EMBEDDED
          commandSucceeded = 1;
#endif
          break;
        }

        //If we see the escape character at the end of the buffer then record up to
        //that point in the buffer excluding the escape char
        //See issue 168: https://github.com/sparkfun/OpenLog/issues/168
        //if(buffer[dataLen] == setting_escape_character)
        //{
        //  //dataLen -= 1; //Adjust dataLen to remove the escape char
        //  tempFile.write((byte*) buffer, dataLen); //write text to file
        //  break; //Quit recording to file
        //}

        //write text to file
        if (tempFile.write((byte*) buffer, dataLen) != dataLen) {
          if ((feedbackMode & EXTENDED_INFO) > 0)
            NewSerial.println(F("error writing to file"));
          break;
        }

        if (dataLen < (sizeof(buffer) - 1)) tempFile.write("\n\r", 2); //If we didn't fill up the buffer then user must have sent NL. Append new line and return
      }

      tempFile.close();
    }
    else if (strcmp_P(commandArg, PSTR("size")) == 0)
    {
      //Argument 2: File name - no wildcard search
      commandArg = getCmdArg(1);
      if (commandArg == 0)
        continue;

      //search file in current directory and open it
      if (tempFile.open(commandArg, O_READ)) {
        NewSerial.print(tempFile.fileSize());
        tempFile.close();
#ifdef INCLUDE_SIMPLE_EMBEDDED
        commandSucceeded = 1;
#endif
      }
      else
      {
        if ((feedbackMode & EXTENDED_INFO) > 0)
          NewSerial.print(F("-1")); //Indicate no file is found
      }
#ifdef INCLUDE_SIMPLE_EMBEDDED
      if ((feedbackMode & EMBEDDED_END_MARKER) == 0)
#endif
        NewSerial.println();
    }
    else if (strcmp_P(commandArg, PSTR("disk")) == 0)
    {
      //Print card type
      NewSerial.print(F("\nCard type: "));
      switch (sd.card()->type()) {
        case SD_CARD_TYPE_SD1:
          NewSerial.println(F("SD1"));
          break;
        case SD_CARD_TYPE_SD2:
          NewSerial.println(F("SD2"));
          break;
        case SD_CARD_TYPE_SDHC:
          NewSerial.println(F("SDHC"));
          break;
        default:
          NewSerial.println(F("Unknown"));
      }

      //Print card information
      cid_t cid;
      if (!sd.card()->readCID(&cid)) {
        NewSerial.print(F("readCID failed"));
        continue;
      }

      NewSerial.print(F("Manufacturer ID: "));
      NewSerial.println(cid.mid, HEX);

      NewSerial.print(F("OEM ID: "));
      NewSerial.print(cid.oid[0]);
      NewSerial.println(cid.oid[1]);

      NewSerial.print(F("Product: "));
      for (byte i = 0; i < 5; i++) {
        NewSerial.print(cid.pnm[i]);
      }

      NewSerial.print(F("\n\rVersion: "));
      NewSerial.print(cid.prv_n, DEC);
      NewSerial.print(F("."));
      NewSerial.println(cid.prv_m, DEC);

      NewSerial.print(F("Serial number: "));
      NewSerial.println(cid.psn);

      NewSerial.print(F("Manufacturing date: "));
      NewSerial.print(cid.mdt_month);
      NewSerial.print(F("/"));
      NewSerial.println(2000 + cid.mdt_year_low + (cid.mdt_year_high << 4));

      csd_t csd;
      uint32_t cardSize = sd.card()->cardSize();
      if (cardSize == 0 || !sd.card()->readCSD(&csd)) {
        NewSerial.println(F("readCSD failed"));
        continue;
      }
      NewSerial.print(F("Card Size: "));
      cardSize *= 0.000512;
      NewSerial.print(cardSize);
      NewSerial.println(F(" MB"));
#ifdef INCLUDE_SIMPLE_EMBEDDED
      commandSucceeded = 1;
#endif
    }
    else if (strcmp_P(commandArg, PSTR("sync")) == 0)
    {
      //This feature has been removed in version 4

#ifdef INCLUDE_SIMPLE_EMBEDDED
      commandSucceeded = 1;
#endif
    }

    //Reset the AVR
    else if (strcmp_P(commandArg, PSTR("reset")) == 0)
    {
      Reset_AVR();
    }

    //Create new file
    else if (strcmp_P(commandArg, PSTR("new")) == 0)
    {
      //Argument 2: File name
      commandArg = getCmdArg(1);
      if (commandArg == 0)
        continue;

      //Try to open file, if fail (file doesn't exist), then break
      if (tempFile.open(commandArg, O_CREAT | O_EXCL | O_WRITE)) {//Will fail if file already exsists
        tempFile.close(); //Everything is good, Close this new file we just opened
#ifdef INCLUDE_SIMPLE_EMBEDDED
        commandSucceeded = 1;
#endif
      }
      else
      {
        if ((feedbackMode & EXTENDED_INFO) > 0) {
          NewSerial.print(F("Error creating file: "));
          NewSerial.println(commandArg);
        }
      }
    }

    //Append to a current file
    else if (strcmp_P(commandArg, PSTR("append")) == 0)
    {
      //Argument 2: File name
      //Find the end of a current file and begins writing to it
      //Ends only when the user inputs Ctrl+z (ASCII 26)
      commandArg = getCmdArg(1);
      if (commandArg == 0)
        continue;
      //appendFile: Uses circular buffer to capture full stream of text and append to file
#ifdef INCLUDE_SIMPLE_EMBEDDED
      commandSucceeded = appendFile(commandArg);
#else
      appendFile(commandArg);
#endif
    }

    else if (strcmp_P(commandArg, PSTR("pwd")) == 0)
    {
      NewSerial.print(F("This command has been removed"));
    }
    // echo <on>|<off>
    else if (strcmp_P(commandArg, PSTR("echo")) == 0)
    {
      //Argument 2: <on>|<off>
      // Set if we are going to echo the characters back to the client or not
      commandArg = getCmdArg(1);
      if (commandArg != 0)
      {
        if ((tempVar = strcmp_P(commandArg, PSTR("on"))) == 0) {
          setting_echo = ON;
          feedbackMode |= ECHO;
        }
        else if ((tempVar = strcmp_P(commandArg, PSTR("off"))) == 0) {
          setting_echo = OFF;
          feedbackMode &= ((byte)~ECHO);
        }

        EEPROM.write(LOCATION_ECHO, setting_echo); //Commit this setting to EEPROM
        recordConfigFile(); //Put this new setting into the config file

#ifdef INCLUDE_SIMPLE_EMBEDDED
        commandSucceeded = (tempVar == 0);
#endif
      }
    }
    // verbose <on>|<off>
    else if (strcmp_P(commandArg, PSTR("verbose")) == 0)
    {
      //Argument 2: <on>|<off>
      // Set if we are going to show extended error information when executing commands
      commandArg = getCmdArg(1);
      if (commandArg != 0)
      {
        if ((tempVar = strcmp_P(commandArg, PSTR("on"))) == 0) {
          setting_verbose = ON;
          feedbackMode |= EXTENDED_INFO;
        }
        else if ((tempVar = strcmp_P(commandArg, PSTR("off"))) == 0) {
          setting_verbose = OFF;
          feedbackMode &= ((byte)~EXTENDED_INFO);
        }

        EEPROM.write(LOCATION_VERBOSE, setting_verbose); //Commit this setting to EEPROM
        recordConfigFile(); //Put this new setting into the config file

#ifdef INCLUDE_SIMPLE_EMBEDDED
        commandSucceeded = (tempVar == 0);
#endif
      }
    }
#ifdef INCLUDE_SIMPLE_EMBEDDED
    //http://code.google.com/p/sdfatlib/issues/detail?id=11 by EdfeldtPeem (Embedded End Marker) <on>|<off>
    else if (strcmp_P(commandArg, PSTR("eem")) == 0)
    {
      //Argument 2: <on>|<off>
      //Set if we are going to enable char 26 (Ctrl+z) as end-of-data
      //marker to separate the returned data and the actual
      //result of the operation
      commandArg = getCmdArg(1);
      if (commandArg != 0)
      {
        if ((tempVar = strcmp_P(commandArg, PSTR("on"))) == 0)
          feedbackMode |= EMBEDDED_END_MARKER;
        else if ((tempVar = strcmp_P(commandArg, PSTR("off"))) == 0)
          feedbackMode &= ((byte)~EMBEDDED_END_MARKER);

        commandSucceeded = (tempVar == 0);
      }
    }

#endif //INCLUDE_SIMPLE_EMBEDDED

    else
    {
      if ((feedbackMode & EXTENDED_INFO) > 0) {
        NewSerial.print(F("unknown command: "));
        NewSerial.println(commandArg);
      }
    }
  }

  //We should never be here
  NewSerial.print(F("Error: Command Exit"));
}

//Reads a line until the \n enter character is found
byte readLine(char* buffer, byte bufferLength)
{
  memset(buffer, 0, bufferLength); //Clear buffer

  byte readLength = 0;
  while (readLength < bufferLength - 1) {
    while (!NewSerial.available());
    byte c = NewSerial.read();

    toggleLED(stat1);

    if (c == 0x08 || c == 0x7f) { //Backspace characters
      if (readLength < 1)
        continue;

      --readLength;
      buffer[readLength] = '\0'; //Put a terminator on the string in case we are finished

      NewSerial.print((char)0x08); //Move back one space
      NewSerial.print(F(" ")); //Put a blank there to erase the letter from the terminal
      NewSerial.print((char)0x08); //Move back again

      continue;
    }

    // Only echo back if this is enabled
    if ((feedbackMode & ECHO) > 0)
      NewSerial.print((char)c);

    if (c == '\r') {
      NewSerial.println();
      buffer[readLength] = '\0';
      break;
    }
    else if (c == '\n') {
      //Do nothing - ignore newlines
      //This was added to v2.51 to make command line control easier from a micro
      //You never know what fprintf or sprintf is going to throw at the buffer
      //See issue 66: https://github.com/nseidle/OpenLog/issues/66
    }
    /*else if (c == setting_escape_character) {
      NewSerial.println();
      buffer[readLength] = c;
      buffer[readLength + 1] = '\0';
      break;
      //If we see an escape character bail recording whatever is in the current buffer
      //up to the escape char
      //This is used mostly when doing the write command where we need
      //To capture the escape command and immediately record
      //the buffer then stop asking for input from user
      //See issue 168: https://github.com/sparkfun/OpenLog/issues/168
    }*/
    else {
      buffer[readLength] = c;
      ++readLength;
    }
  }

  //Split the command line into arguments
  splitCmdLineArgs(buffer, bufferLength);

  return readLength;
}

void printMenu(void)
{
  NewSerial.println(F("OpenLog v4.0"));
  NewSerial.println(F("Basic commands:"));
  NewSerial.println(F("new <file>\t\t: Creates <file>"));
  NewSerial.println(F("append <file>\t\t: Appends text to end of <file>"));

  //NewSerial.println(F("write <file> <offset>\t: Writes text to <file>, starting from <offset>. The text is read from the UART, line by line. Finish with an empty line"));
  //NewSerial.println(F("rm <file>\t\t: Deletes <file>. Use wildcard to do a wildcard removal of files"));

  NewSerial.println(F("md <directory>\t\t: Creates a <directory>"));

  //NewSerial.println(F("cd <directory>\t\t: Changes current working directory to <directory>"));
  //NewSerial.println(F("cd ..\t\t: Changes to lower directory in tree"));

  NewSerial.println(F("ls\t\t\t: Shows the content of the current directory.."));
  NewSerial.println(F("read <file> <start> <length> <type>: Outputs <length> bytes of <file> to the terminal starting at <start>. Omit <start> and <length> to read whole file. <type> 1 prints in ASCII, 2 in HEX."));
  NewSerial.println(F("size <file>\t\t: Write size of <file> to terminal"));
  NewSerial.println(F("disk\t\t\t: Shows card information"));

  //NewSerial.println(F("init\t\t\t: Reinitializes and reopens the memory card"));
  //NewSerial.println(F("sync\t\t\t: Ensures all buffered data is written to the card"));

  NewSerial.println(F("reset\t\t\t: Causes unit to reset, uses parameters in config file"));
  NewSerial.println(F("set\t\t\t: Menu to configure system mode"));
  NewSerial.println(F("baud\t\t\t: Menu to configure baud rate"));
}

//Configure what baud rate to communicate at
void baudMenu(void)
{
  long uartSpeed = readBaud();

  NewSerial.print(F("\n\rCurrent rate: "));
  NewSerial.print(uartSpeed, DEC);
  NewSerial.println(F(" bps"));

  NewSerial.println(F("Enter new baud rate ('x' to exit):"));

  //Print prompt
  NewSerial.print(F(">"));

  //Read user input
  char newBaud[8]; //Max at 1000000
  readLine(newBaud, sizeof(newBaud));

  if (newBaud[0] == 'x')
  {
    NewSerial.println(F("Exiting"));
    return; //Look for escape character
  }

  long newRate = strToLong(newBaud); //Convert this string to a long

  if (newRate < BAUD_MIN || newRate > BAUD_MAX)
  {
    NewSerial.println(F("Out of bounds"));
  }
  else
  {
    NewSerial.print(F("Going to "));
    NewSerial.print(newRate);
    NewSerial.println(F("bps"));

    //Record this new baud rate
    writeBaud(newRate);
    recordConfigFile(); //Put this new setting into the config file
    blinkError(ERROR_NEW_BAUD);
    //Do nothing. Unit will now be in infinite blinkError loop
  }
}


//Change how OpenLog works
//1) Turn on unit, unit will create new file, and just start logging
//2) Turn on, append to known file, and just start logging
//3) Turn on, sit at command prompt
//4) Resets the newLog file number to zero
void systemMenu(void)
{
  byte systemMode = EEPROM.read(LOCATION_SYSTEM_SETTING);

  while (1)
  {
    NewSerial.println(F("\r\nSystem Configuration"));

    NewSerial.print(F("Current boot mode: "));
    if (systemMode == MODE_NEWLOG) NewSerial.print(F("New file"));
    if (systemMode == MODE_SEQLOG) NewSerial.print(F("Append file"));
    if (systemMode == MODE_COMMAND) NewSerial.print(F("Command"));
    NewSerial.println();

    NewSerial.print(F("Current escape character and amount: "));
    NewSerial.print(setting_escape_character, DEC);
    NewSerial.print(F(" x "));
    NewSerial.println(setting_max_escape_character, DEC);

    NewSerial.println(F("Change to:"));
    NewSerial.println(F("1) New file logging"));
    NewSerial.println(F("2) Append file logging"));
    NewSerial.println(F("3) Command prompt"));
    NewSerial.println(F("4) Reset new file number"));
    NewSerial.println(F("5) New escape character"));
    NewSerial.println(F("6) Number of escape characters"));

#if DEBUG
    NewSerial.println(F("a) Clear all user settings"));
#endif

    NewSerial.println(F("x) Exit"));
    //Print prompt
    NewSerial.print(F(">"));

    //Read command
    while (!NewSerial.available());
    char command = NewSerial.read();

    //Execute command
    if (command == '1')
    {
      NewSerial.println(F("New file logging"));
      EEPROM.write(LOCATION_SYSTEM_SETTING, MODE_NEWLOG);
      recordConfigFile(); //Put this new setting into the config file
      return;
    }
    if (command == '2')
    {
      NewSerial.println(F("Append file logging"));
      EEPROM.write(LOCATION_SYSTEM_SETTING, MODE_SEQLOG);
      recordConfigFile(); //Put this new setting into the config file
      return;
    }
    if (command == '3')
    {
      NewSerial.println(F("Command prompt"));
      EEPROM.write(LOCATION_SYSTEM_SETTING, MODE_COMMAND);
      recordConfigFile(); //Put this new setting into the config file
      return;
    }
    if (command == '4')
    {
      NewSerial.println(F("New file number reset to zero"));
      EEPROM.write(LOCATION_FILE_NUMBER_LSB, 0);
      EEPROM.write(LOCATION_FILE_NUMBER_MSB, 0);

      //65533 log testing
      //EEPROM_write(LOCATION_FILE_NUMBER_LSB, 0xFD);
      //EEPROM_write(LOCATION_FILE_NUMBER_MSB, 0xFF);
      return;
    }
    if (command == '5')
    {
      NewSerial.print(F("Enter a new escape character: "));

      while (!NewSerial.available()); //Wait for user to hit character
      setting_escape_character = NewSerial.read();

      EEPROM.write(LOCATION_ESCAPE_CHAR, setting_escape_character);
      recordConfigFile(); //Put this new setting into the config file

      NewSerial.print(F("\n\rNew escape character: "));
      NewSerial.println(setting_escape_character, DEC);
      return;
    }
    if (command == '6')
    {
      byte choice = 255;
      while (choice == 255)
      {
        NewSerial.print(F("\n\rEnter number of escape characters to look for (0 to 254): "));
        while (!NewSerial.available()); //Wait for user to hit character
        choice = NewSerial.read() - '0';
      }

      setting_max_escape_character = choice;
      EEPROM.write(LOCATION_MAX_ESCAPE_CHAR, setting_max_escape_character);
      recordConfigFile(); //Put this new setting into the config file

      NewSerial.print(F("\n\rNumber of escape characters needed: "));
      NewSerial.println(setting_max_escape_character, DEC);
      return;
    }

#if DEBUG
    //This allows us to reset the EEPROM and config file on a unit to see what would happen to an
    //older unit that is upgraded/reflashed to newest firmware
    if (command == 'a')
    {
      //EEPROM.write(LOCATION_BAUD_SETTING, 0xFF);
      EEPROM.write(LOCATION_SYSTEM_SETTING, 0xFF);
      EEPROM.write(LOCATION_FILE_NUMBER_LSB, 0xFF);
      EEPROM.write(LOCATION_FILE_NUMBER_MSB, 0xFF);
      EEPROM.write(LOCATION_ESCAPE_CHAR, 0xFF);
      EEPROM.write(LOCATION_MAX_ESCAPE_CHAR, 0xFF);

      //Remove the config file if it is there
      SdFile myFile;
      if (!sd.chdir()) systemError(ERROR_ROOT_INIT); // open the root directory

      char configFileName[strlen(CFG_FILENAME)];
      strcpy_P(configFileName, PSTR(CFG_FILENAME)); //This is the name of the config file. 'config.sys' is probably a bad idea.

      //If there is currently a config file, trash it
      if (myFile.open(configFileName, O_WRITE)) {
        if (!myFile.remove()) {
          NewSerial.println(F("Remove config failed"));
          myFile.close(); //Close this file
          return;
        }
      }

      NewSerial.println(F("Unit has been reset. Please power cycle"));
      while (1);
    }
#endif

    if (command == 'x')
    {
      //Do nothing, just exit
      NewSerial.println(F("Exiting"));
      return;
    }
  }
}

//A rudimentary way to convert a string to a long 32 bit integer
//Used by the read command, in command shell and baud from the system menu
uint32_t strToLong(const char* str)
{
  uint32_t l = 0;
  while (*str >= '0' && *str <= '9')
    l = l * 10 + (*str++ - '0');

  return l;
}

//Returns the number of command line arguments
byte countCmdArgs(void)
{
  byte count = 0;
  byte i = 0;
  for (; i < MAX_COUNT_COMMAND_LINE_ARGS; i++)
    if ((cmd_arg[i].arg != 0) && (cmd_arg[i].arg_length > 0))
      count++;

  return count;
}

//Safe index handling of command line arguments
char general_buffer[30]; //Needed for command shell
#define MIN(a,b) ((a)<(b))?(a):(b)
char* getCmdArg(byte index)
{
  memset(general_buffer, 0, sizeof(general_buffer));
  if (index < MAX_COUNT_COMMAND_LINE_ARGS)
    if ((cmd_arg[index].arg != 0) && (cmd_arg[index].arg_length > 0))
      return strncpy(general_buffer, cmd_arg[index].arg, MIN(sizeof(general_buffer), cmd_arg[index].arg_length));

  return 0;
}

//Safe adding of command line arguments
void addCmdArg(char* buffer, byte bufferLength)
{
  byte count = countCmdArgs();
  if (count < MAX_COUNT_COMMAND_LINE_ARGS)
  {
    cmd_arg[count].arg = buffer;
    cmd_arg[count].arg_length = bufferLength;
  }
}

//Split the command line arguments
//Example:
//	read <filename> <start> <length>
//	arg[0] -> read
//	arg[1] -> <filename>
//	arg[2] -> <start>
//	arg[3] -> <end>
byte splitCmdLineArgs(char* buffer, byte bufferLength)
{
  byte arg_index_start = 0;
  byte arg_index_end = 1;

  //Reset command line arguments
  memset(cmd_arg, 0, sizeof(cmd_arg));

  //Split the command line arguments
  while (arg_index_end < bufferLength)
  {
    //Search for ASCII 32 (Space)
    if ((buffer[arg_index_end] == ' ') || (arg_index_end + 1 == bufferLength))
    {
      //Fix for last character
      if (arg_index_end + 1 == bufferLength)
        arg_index_end = bufferLength;

      //Add this command line argument to the list
      addCmdArg(&(buffer[arg_index_start]), (arg_index_end - arg_index_start));
      arg_index_start = ++arg_index_end;
    }

    arg_index_end++;
  }

  //Return the number of available command line arguments
  return countCmdArgs();
}

//The following functions are required for wildcard use
//=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=

//Returns char* pointer to buffer if buffer is a valid number or
//0(null) if not.
char* isNumber(char* buffer, byte bufferLength)
{
  for (int i = 0; i < bufferLength; i++)
    if (!isdigit(buffer[i]))
      return 0;

  return buffer;
}
void removeErrorCallback(const char* fileName)
{
  NewSerial.print((char *)F("Remove failed: "));
  NewSerial.println(fileName);
}

//Wildcard string compare.
//Written by Jack Handy - jakkhandy@hotmail.com
//http://www.codeproject.com/KB/string/wildcmp.aspx
byte wildcmp(const char* wild, const char* string)
{
  const char *cp = 0;
  const char *mp = 0;

  while (*string && (*wild != '*'))
  {
    if ((*wild != *string) && (*wild != '?'))
      return 0;

    wild++;
    string++;
  }

  while (*string)
  {
    if (*wild == '*')
    {
      if (!(*(++wild)))
        return 1;

      mp = wild;
      cp = string + 1;
    }
    else if ((*wild == *string) || (*wild == '?'))
    {
      wild++;
      string++;
    }
    else
    {
      wild = mp;
      string = cp++;
    }
  }

  while (*wild == '*')
    wild++;
  return !(*wild);
}

//End wildcard functions
//=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=

//------------------------------------------------------------------------------
// Listing functions
//  - Modeled loosely on the ls() methods in SdBaseFile.cpp from the SdFat library.
// Written by dlkeng in relation to issue 135 https://github.com/sparkfun/OpenLog/issues/135

#define WAS_EOF             0
#define WAS_FILE            1
#define WAS_SUBDIR          2
#define FILENAME_EXT_SIZE   13
#define LS_FIELD_SIZE       (FILENAME_EXT_SIZE + 1)
#define SUBDIR_INDENT       2
#define DIR_SIZE            (sizeof(dir_t))

/*
 * NAME:
 *  void lsPrint(SdFile * theDir, char * cmdStr, byte flags, byte indent)
 *
 * PARAMETERS:
 *  SdFile * theDir = the directory to list (assumed opened)
 *  char * cmdStr = the command line file/directory string (with possible wildcards)
 *  byte flags = the inclusive OR of
 *                  LS_SIZE - print the file size
 *                  LS_R - recursively list subdirectories
 *  byte indent = amount of space before file name
 *                (used for recursive list to indicate subdirectory level)
 *
 * WHAT:
 *  List directory contents to serial port.
 *
 *  Wildcard support rules:
 *    Wildcard characters ('*', '?') only apply to the selection of filenames to
 *    list, not to the listing of directory or subdirectory names. All directory
 *    and subdirectory names are always listed.
 *
 * RETURN VALUES:
 *  None.
 *
 * SPECIAL CONSIDERATIONS:
 *  May be called recursively with limited recursion depth (see FOLDER_TRACK_DEPTH).
 *  Each recursion uses ~50 bytes of RAM.
 */
//void lsPrint(SdFile * theDir, char * cmdStr, byte flags, byte indent)
void lsPrint(FatFile * theDir, char * cmdStr, byte flags, byte indent)
{

#define FOLDER_TRACK_DEPTH 2

  static byte depth = 0;      // current recursion depth
  byte status;
  uint16_t index;
  SdFile subdir;

  theDir->rewind();
  while ((status = lsPrintNext(theDir, cmdStr, flags, indent)))
  {
    if ((status == WAS_SUBDIR) && (flags & LS_R) && (depth < FOLDER_TRACK_DEPTH))
    {
      // was a subdirectory, recursion allowed, recursion depth OK

      index = (theDir->curPosition() / DIR_SIZE) - 1;  // determine current directory entry index
      if (subdir.open(theDir, index, O_READ))
      {
        ++depth;        // limit recursion
        lsPrint(&subdir, cmdStr, flags, indent + SUBDIR_INDENT); // recursively list subdirectory
        --depth;
        subdir.close();
      }
    }
  }
}

/*
 * NAME:
 *  void lsPrintNext(SdFile * theDir, char * cmdStr, byte flags, byte indent)
 *
 * PARAMETERS:
 *  SdFile * theDir = the directory to list (assumed opened)
 *  char * cmdStr = the command line file/directory string (with possible wildcards)
 *  byte flags = the inclusive OR of
 *                  LS_SIZE - print the file size
 *                  LS_R - recursively list subdirectories
 *  byte indent = amount of space before file name
 *                (used for recursive list to indicate subdirectory level)
 *
 * WHAT:
 *  List directory's next contents to serial port.
 *
 *  Wildcard support rules:
 *    Wildcard characters ('*', '?') only apply to the selection of filenames to
 *    list, not to the listing of directory or subdirectory names. All directory
 *    and subdirectory names are always listed.
 *
 * RETURN VALUES:
 *  byte = WAS_EOF - EOF, WAS_FILE - normal file, or WAS_SUBDIR - subdirectory
 *
 * SPECIAL CONSIDERATIONS:
 *  None.
 */
//byte lsPrintNext(SdFile * theDir, char * cmdStr, byte flags, byte indent)
byte lsPrintNext(FatFile * theDir, char * cmdStr, byte flags, byte indent)
{
  byte pos = 0;           // output position
  byte open_stat;         // file open status
  byte status;            // return status
  SdFile tempFile;
  char fname[FILENAME_EXT_SIZE];

  // Find next available object to display in the specified directory
  while ((open_stat = tempFile.openNext(theDir, O_READ)))
  {
    //    if (tempFile.getFilename(fname)) // Get the filename of the object we're looking at
    if (tempFile.getSFN(fname)) // Get the filename of the object we're looking at
    {
      if (tempFile.isDir() || tempFile.isFile() || tempFile.isSubDir())
      {
        if (tempFile.isFile())        // wildcards only apply to files
        {
          if (wildcmp(cmdStr, fname)) // see if it matches the wildcard
          {
            status = WAS_FILE;
            break;      // is a matching file name, display it
          }
          // else skip it
        }
        else    // is a subdirectory
        {
          status = WAS_SUBDIR;
          break;        // display subdirectory name
        }
      }
    }
    tempFile.close();
  }
  if (!open_stat)
  {
    return WAS_EOF;     // nothing more in this (sub)directory
  }

  // output the file or directory name

  // indent for dir level
  for (byte i = 0; i < indent; i++)
  {
    NewSerial.print(F(" "));
  }

  // print name
  pos += NewSerial.print(fname);

  if (tempFile.isSubDir())
  {
    pos += NewSerial.print(F("/"));    // subdirectory indicator
  }
  // print size if requested (files only)
  if (tempFile.isFile() && (flags & LS_SIZE))
  {
    while (pos++ < LS_FIELD_SIZE)
    {
      NewSerial.print(F(" "));
    }
    NewSerial.print(F(" "));        // ensure at least 1 separating space
    NewSerial.print(tempFile.fileSize());
  }
  NewSerial.println();
  tempFile.close();
  return status;
}

//Given a pin, it will toggle it from high to low or vice versa
void toggleLED(byte pinNumber)
{
  if (digitalRead(pinNumber)) digitalWrite(pinNumber, LOW);
  else digitalWrite(pinNumber, HIGH);
}