diff --git a/SIO2Arduino.ino b/SIO2Arduino.ino
index e0bc317..f8b99dc 100644
--- a/SIO2Arduino.ino
+++ b/SIO2Arduino.ino
@@ -23,6 +23,7 @@
 #include "config.h"
 #include <SdFat.h>
 #include <SdFatUtil.h>
+#include <SdVolume.h>
 #include "atari.h"
 #include "sio_channel.h"
 #include "disk_drive.h"
@@ -44,7 +45,7 @@ DiskDrive drive1;
 #ifdef SELECTOR_BUTTON
 boolean isSwitchPressed = false;
 unsigned long lastSelectionPress;
-boolean isFileOpened;
+boolean isFileOpened=false;
 #endif
 #ifdef RESET_BUTTON
 unsigned long lastResetPress;
@@ -64,51 +65,53 @@ void setup() {
 
   // set pin modes
   #ifdef SELECTOR_BUTTON
-  pinMode(PIN_SELECTOR, INPUT);
+  pinMode(PIN_SELECTOR, INPUT_PULLUP);
   #endif
   #ifdef RESET_BUTTON
-  pinMode(PIN_RESET, INPUT);
+  pinMode(PIN_RESET, INPUT_PULLUP);
   #endif
 
   #ifdef LCD_DISPLAY
   // set up LCD if appropriate
   lcd.begin(16, 2);
-  lcd.print("SIO2Arduino");
+  lcd.print(F("SIO2Arduino"));
   lcd.setCursor(0,1);
   #endif
 
   // initialize SD card
-  LOG_MSG("Initializing SD card...");
+  LOG_MSG(F("Initializing SD card..."));
   pinMode(PIN_SD_CS, OUTPUT);
 
   if (!card.init(SPI_HALF_SPEED, PIN_SD_CS)) {
-    LOG_MSG_CR(" failed.");
+    LOG_MSG_CR(F(" failed."));
     #ifdef LCD_DISPLAY
-      lcd.print("SD Init Error");
+      lcd.print(F("SD Init Error"));
     #endif     
     return;
   }
   
   if (!volume.init(&card)) {
-    LOG_MSG_CR(" failed.");
+    LOG_MSG_CR(F(" failed."));
     #ifdef LCD_DISPLAY
-      lcd.print("SD Volume Error");
+      lcd.print(F("SD Volume Error"));
     #endif     
     return;
   }
 
   if (!currDir.openRoot(&volume)) {
-    LOG_MSG_CR(" failed.");
+    LOG_MSG_CR(F(" failed."));
     #ifdef LCD_DISPLAY
-      lcd.print("SD Root Error");
+      lcd.print(F("SD Root Error"));
     #endif     
     return;
   }
 
-  LOG_MSG_CR(" done.");
+  LOG_MSG_CR(F(" done."));
   #ifdef LCD_DISPLAY
-    lcd.print("READY");
+    lcd.print(F("READY"));
+    delay(3000);
   #endif
+  mountFilename(0, "AUTORUN.ATR");
 }
 
 void loop() {
@@ -117,15 +120,14 @@ void loop() {
   
   #ifdef SELECTOR_BUTTON
   // watch the selector button (accounting for debounce)
-  if (digitalRead(PIN_SELECTOR) == HIGH && millis() - lastSelectionPress > 250) {
+  if (digitalRead(PIN_SELECTOR) == LOW && millis() - lastSelectionPress > 250 && isSwitchPressed==false) {
     lastSelectionPress = millis();
     changeDisk(0);
-  }
+  } else isSwitchPressed=(digitalRead(PIN_SELECTOR) == LOW);
   #endif
-  
   #ifdef RESET_BUTTON
   // watch the reset button
-  if (digitalRead(PIN_RESET) == HIGH && millis() - lastResetPress > 250) {
+  if (digitalRead(PIN_RESET) == LOW && millis() - lastResetPress > 250) {
     lastResetPress = millis();
     mountFilename(0, "AUTORUN.ATR");
   }
@@ -162,19 +164,19 @@ boolean format(int deviceId, int density) {
   char name[13];
   
   // get current filename
-  file.getFilename(name);
+  file.getName(name, 13);
 
   // close and delete the current file
   file.close();
   file.remove();
 
-  LOG_MSG("Remove old file: ");
+  LOG_MSG(F("Remove old file: "));
   LOG_MSG_CR(name);
 
   // open new file for writing
   file.open(&currDir, name, O_RDWR | O_SYNC | O_CREAT);
 
-  LOG_MSG("Created new file: ");
+  LOG_MSG(F("Created new file: "));
   LOG_MSG_CR(name);
 
   // allow the virtual drive to format the image (and possibly alter its size)
@@ -346,4 +348,4 @@ boolean mountFilename(int deviceId, char *name) {
   }
   
   return false;
-}
+}
diff --git a/config.h b/config.h
index 96b4dde..9e3ff19 100644
--- a/config.h
+++ b/config.h
@@ -23,6 +23,7 @@
 #ifndef CONFIG_H
 #define CONFIG_H
 
+#define USE_SD_VOLUME
 /**
  * These are SIO2Arduino feature definitions.
  */
@@ -40,7 +41,7 @@
 // Uncomment this line if you are using a hardware button for image selection
 #define SELECTOR_BUTTON
 
-// Uncomment this line if you want a reset button (automatically mounts /AUTORUN.ATR)
+// Uncomment this line if you want a reset button (automatically mounts /AUTORUN.ATR) (deprecated, AUTORUN.ATR always mounted if it exists)
 //#define RESET_BUTTON
 
 // uncomment if using an Ethernet shield for SD capabilities
@@ -132,6 +133,7 @@
   #define SIO_CALLBACK serialEvent
 #endif
 
+//#define DEBUG
 /**
  * Logging/debug config
  */
diff --git a/disk_image.cpp b/disk_image.cpp
index 218dd49..8572c4c 100644
--- a/disk_image.cpp
+++ b/disk_image.cpp
@@ -252,9 +252,9 @@ boolean DiskImage::loadFile(SdFile *file) {
     m_sectorSize = atrHeader->secSize;
     m_sectorReadDelay = 0;
     
-    LOG_MSG("Loaded ATR with sector size ");
+    LOG_MSG(F("Loaded ATR with sector size "));
     LOG_MSG(atrHeader->secSize);
-    LOG_MSG(": ");
+    LOG_MSG(F(": "));
     
     return true;
   }
@@ -288,7 +288,7 @@ boolean DiskImage::loadFile(SdFile *file) {
         break;
     }
 
-    LOG_MSG("Loaded PRO with sector size 128: ");
+    LOG_MSG(F("Loaded PRO with sector size 128: "));
 
     return true;
   }
@@ -383,12 +383,12 @@ boolean DiskImage::loadFile(SdFile *file) {
       file->seekSet(fileIndex);
     }
 
-    LOG_MSG("Loaded ATX with sector size 128: ");
+    LOG_MSG(F("Loaded ATX with sector size 128: "));
     return true;
   }  
 #endif
 
-  file->getFilename((char*)&filename);
+  file->getName((char*)&filename, 13);
   int len = strlen(filename);
   char *extension = filename + len - 4;
 
@@ -401,7 +401,7 @@ boolean DiskImage::loadFile(SdFile *file) {
     m_sectorSize = SECTOR_SIZE_SD;
     m_sectorReadDelay = 0;
 
-    LOG_MSG("Loaded XFD with sector size 128: ");
+    LOG_MSG(F("Loaded XFD with sector size 128: "));
     return true;
 #ifdef XEX_IMAGES    
   } else if ((!strcmp(".XEX", extension) || !strcmp(".xex", extension))) {
@@ -415,7 +415,7 @@ boolean DiskImage::loadFile(SdFile *file) {
     KBOOT_LOADER[9] = m_fileSize & 0xFF;
     KBOOT_LOADER[10] = m_fileSize >> 8;
     
-    LOG_MSG("Loaded XEX with sector size 128: ");
+    LOG_MSG(F("Loaded XEX with sector size 128: "));
     return true;
 #endif    
   }
diff --git a/readme.txt b/readme.txt
index 90702af..cf2a3fd 100644
--- a/readme.txt
+++ b/readme.txt
@@ -1,6 +1,6 @@
 SIO2Arduino is an open-source implementation of the Atari SIO device protocol that runs on Arduino hardware. Arduino hardware is open-source and can be assembled by hand or purchased preassembled.
 
-Note: You will need the SdFat library (http://code.google.com/p/sdfatlib/) in your Arduino libraries directory in order to compile.
+Note: You will need the SdFat library (https://github.com/greiman/SdFat) in your Arduino libraries directory in order to compile.
 
 For more information on SIO2Arduino, see the website at: 
 http://www.whizzosoftware.com/sio2arduino
diff --git a/sdrive.cpp b/sdrive.cpp
index b600395..d95be64 100644
--- a/sdrive.cpp
+++ b/sdrive.cpp
@@ -268,49 +268,49 @@ boolean SDriveHandler::printCmdName(byte cmd) {
 #ifdef DEBUG
   switch (cmd) {
     case CMD_SDRIVE_IDENT:
-      LOG_MSG("SDRIVE IDENT");
+      LOG_MSG(F("SDRIVE IDENT"));
       break;
     case CMD_SDRIVE_INIT:
-      LOG_MSG("SDRIVE INIT");
+      LOG_MSG(F("SDRIVE INIT"));
       break;
     case CMD_SDRIVE_CHROOT:
-      LOG_MSG("SDRIVE CHROOT");
+      LOG_MSG(F("SDRIVE CHROOT"));
       break;
     case CMD_SDRIVE_SWAP_VDN:
-      LOG_MSG("SDRIVE SWAP VDN");
+      LOG_MSG(F("SDRIVE SWAP VDN"));
       break;
     case CMD_SDRIVE_GETPARAMS:
-      LOG_MSG("SDRIVE GETPARAMS");
+      LOG_MSG(F("SDRIVE GETPARAMS"));
       break;
     case CMD_SDRIVE_GET_ENTRIES:
-      LOG_MSG("SDRIVE GET ENTRIES");
+      LOG_MSG(F("SDRIVE GET ENTRIES"));
       break;
     case CMD_SDRIVE_CHDIR_VDN:
-      LOG_MSG("SDRIVE CHDIR VDN");
+      LOG_MSG(F("SDRIVE CHDIR VDN"));
       break;
     case CMD_SDRIVE_CHDIR:
-      LOG_MSG("SDRIVE CHDIR");
+      LOG_MSG(F("SDRIVE CHDIR"));
       break;
     case CMD_SDRIVE_CHDIR_UP:
-      LOG_MSG("SDRIVE CHDIR UP");
+      LOG_MSG(F("SDRIVE CHDIR UP"));
       break;
     case CMD_SDRIVE_GET20:
-      LOG_MSG("SDRIVE GET20");
+      LOG_MSG(F("SDRIVE GET20"));
       break;
     case CMD_SDRIVE_MOUNT_D0:
-      LOG_MSG("SDRIVE MOUNTvD0");
+      LOG_MSG(F("SDRIVE MOUNTvD0"));
       break;
     case CMD_SDRIVE_MOUNT_D1:
-      LOG_MSG("SDRIVE MOUNTvD1");
+      LOG_MSG(F("SDRIVE MOUNTvD1"));
       break;
     case CMD_SDRIVE_MOUNT_D2:
-      LOG_MSG("SDRIVE MOUNTvD2");
+      LOG_MSG(F("SDRIVE MOUNTvD2"));
       break;
     case CMD_SDRIVE_MOUNT_D3:
-      LOG_MSG("SDRIVE MOUNTvD3");
+      LOG_MSG(F("SDRIVE MOUNTvD3"));
       break;
     case CMD_SDRIVE_MOUNT_D4:
-      LOG_MSG("SDRIVE MOUNTvD4");
+      LOG_MSG(F("SDRIVE MOUNTvD4"));
       break;
     default:
       return false;
diff --git a/sio_channel.cpp b/sio_channel.cpp
index 190d44d..0fa8d43 100644
--- a/sio_channel.cpp
+++ b/sio_channel.cpp
@@ -127,9 +127,9 @@ void SIOChannel::processIncomingByte() {
       break;
     }
     default:
-      LOG_MSG("Ignoring byte ");
+      LOG_MSG(F("Ignoring byte "));
       LOG_MSG(b, HEX);
-      LOG_MSG(" in state ");
+      LOG_MSG(F(" in state "));
       LOG_MSG_CR(m_cmdPinState);
       break;
   }
@@ -138,9 +138,9 @@ void SIOChannel::processIncomingByte() {
 boolean SIOChannel::isChecksumValid() {
   byte chkSum = checksum((byte*)&m_cmdFrame, 4);
   if (chkSum != m_cmdFrame.checksum) {
-    LOG_MSG("Checksum failed. Calculated: ");
+    LOG_MSG(F("Checksum failed. Calculated: "));
     LOG_MSG(chkSum);
-    LOG_MSG("; received: ");
+    LOG_MSG(F("; received: "));
     LOG_MSG_CR(m_cmdFrame.checksum);
 
     return false;
@@ -298,7 +298,7 @@ void SIOChannel::doPutSector() {
       // send COMPLETE
       m_stream->write(COMPLETE);
     } else {
-      LOG_MSG_CR("Write to device error");
+      LOG_MSG_CR(F("Write to device error"));
       m_stream->write(ERR);
     }
   // otherwise, NAK it
@@ -306,9 +306,9 @@ void SIOChannel::doPutSector() {
     delay(DELAY_T4);
     m_stream->write(NAK);
 
-    LOG_MSG("Data frame checksum error: ");
+    LOG_MSG(F("Data frame checksum error: "));
     LOG_MSG(chksum, HEX);
-    LOG_MSG(" vs. ");
+    LOG_MSG(F(" vs. "));
     LOG_MSG_CR(m_sectorBuffer[sectorSize], HEX);
   }
 
@@ -352,7 +352,7 @@ void SIOChannel::cmdFormat(int deviceId, int density) {
     delay(DELAY_T5);
     m_stream->write(COMPLETE);
     
-    LOG_MSG("Sending data frame of length ");
+    LOG_MSG(F("Sending data frame of length "));
     LOG_MSG_CR(SD_SECTOR_SIZE);
 
     m_stream->write(0xFF);
@@ -372,44 +372,44 @@ void SIOChannel::dumpCommandFrame() {
 // we only compile this on DEBUG to save allocating string constants
 #ifdef DEBUG
   LOG_MSG(m_cmdFrame.deviceId, HEX);
-  LOG_MSG(" ");
+  LOG_MSG(F(" "));
   LOG_MSG(m_cmdFrame.command, HEX);
-  LOG_MSG(" ");
+  LOG_MSG(F(" "));
   LOG_MSG(m_cmdFrame.aux1, HEX);
-  LOG_MSG(" ");
+  LOG_MSG(F(" "));
   LOG_MSG(m_cmdFrame.aux2, HEX);
-  LOG_MSG(" ");
+  LOG_MSG(F(" "));
   LOG_MSG(m_cmdFrame.checksum, HEX);
-  LOG_MSG(" : ");
+  LOG_MSG(F(" : "));
   
   switch (m_cmdFrame.command) {
     case CMD_STATUS:
-      LOG_MSG("STATUS");
+      LOG_MSG(F("STATUS"));
       break;
     case CMD_POLL:
-      LOG_MSG("POLL");
+      LOG_MSG(F("POLL"));
       break;
     case CMD_READ:
-      LOG_MSG("READ ");
+      LOG_MSG(F("READ "));
       LOG_MSG(getCommandSector());
       break;
     case CMD_WRITE:
-      LOG_MSG("WRITE ");
+      LOG_MSG(F("WRITE "));
       LOG_MSG(getCommandSector());
       break;
     case CMD_PUT:
-      LOG_MSG("PUT ");
+      LOG_MSG(F("PUT "));
       LOG_MSG(getCommandSector());
       break;
     case CMD_FORMAT:
-      LOG_MSG("FORMAT");
+      LOG_MSG(F("FORMAT"));
       break;
     case CMD_FORMAT_MD:
-      LOG_MSG("FORMAT MD");
+      LOG_MSG(F("FORMAT MD"));
       break;
     default:
       if (!m_sdriveHandler.printCmdName(m_cmdFrame.command)) {
-        LOG_MSG("??");
+        LOG_MSG(F("??"));
       }
   }