diff --git a/Cart_Reader/2600.ino b/Cart_Reader/2600.ino
index 32e234c..13b9850 100644
--- a/Cart_Reader/2600.ino
+++ b/Cart_Reader/2600.ino
@@ -171,7 +171,7 @@ void readSegment_2600(uint16_t startaddr, uint16_t endaddr) {
 }
 
 void readDataArray_2600(uint16_t addr, uint16_t size) {
-    for (int w = 0; w < size; w++) {
+    for (uint16_t w = 0; w < size; w++) {
       sdBuffer[w] = readData_2600(addr + w);
     }
     myFile.write(sdBuffer, size);
@@ -709,9 +709,9 @@ setmapper:
 //******************************************
 // CART SELECT CODE
 //******************************************
-void readDataLine_2600(FsFile& database, byte* gameMapper) {
+void readDataLine_2600(FsFile& database, void* gameMapper) {
   // Read mapper with three ascii character and subtract 48 to convert to decimal
-  (*gameMapper) = ((database.read() - 48) * 100) + ((database.read() - 48) * 10) + (database.read() - 48);
+  (*(byte*)gameMapper) = ((database.read() - 48) * 100) + ((database.read() - 48) * 10) + (database.read() - 48);
 
   // Skip rest of line
   database.seekCur(2);
diff --git a/Cart_Reader/5200.ino b/Cart_Reader/5200.ino
index 5d9d2aa..d1c743d 100644
--- a/Cart_Reader/5200.ino
+++ b/Cart_Reader/5200.ino
@@ -508,30 +508,11 @@ setmapper:
 //******************************************
 // CART SELECT CODE
 //******************************************
-struct database_entry_5200 {
-  byte gameMapper;
-  byte gameSize;
-};
-
-void readDataLine_5200(FsFile& database, struct database_entry_5200* entry) {
-  // Read mapper
-  entry->gameMapper = database.read() - 48;
-
-  // Skip over semicolon
-  database.seekCur(1);
-
-  // Read rom size
-  entry->gameSize = database.read() - 48;
-
-  // Skip rest of line
-  database.seekCur(2);
-}
-
 void setCart_5200() {
   //go to root
   sd.chdir();
 
-  struct database_entry_5200 entry;
+  struct database_entry_mapper_size entry;
 
   // Select starting letter
   byte myLetter = starting_letter();
@@ -540,7 +521,7 @@ void setCart_5200() {
   if (myFile.open("5200.txt", O_READ)) {
     seek_first_letter_in_database(myFile, myLetter);
 
-    if(checkCartSelection(myFile, &readDataLine_5200, &entry)) {
+    if(checkCartSelection(myFile, &readDataLineMapperSize, &entry)) {
       EEPROM_writeAnything(7, entry.gameMapper);
       EEPROM_writeAnything(8, entry.gameSize);
     }
diff --git a/Cart_Reader/7800.ino b/Cart_Reader/7800.ino
index 357c987..157ee29 100644
--- a/Cart_Reader/7800.ino
+++ b/Cart_Reader/7800.ino
@@ -664,30 +664,12 @@ setmapper:
 //******************************************
 // CART SELECT CODE
 //******************************************
-struct database_entry_7800 {
-  byte gameMapper;
-  byte gameSize;
-};
-
-void readDataLine_7800(FsFile& database, struct database_entry_7800* entry) {
-  // Read mapper
-  entry->gameMapper = database.read() - 48;
-
-  // Skip over semicolon
-  database.seekCur(1);
-
-  // Read rom size
-  entry->gameSize = database.read() - 48;
-
-  // Skip rest of line
-  database.seekCur(2);
-}
 
 void setCart_7800() {
   //go to root
   sd.chdir();
 
-  struct database_entry_7800 entry;
+  struct database_entry_mapper_size entry;
 
   // Select starting letter
   byte myLetter = starting_letter();
@@ -696,7 +678,7 @@ void setCart_7800() {
   if (myFile.open("7800.txt", O_READ)) {
     seek_first_letter_in_database(myFile, myLetter);
 
-    if(checkCartSelection(myFile, &readDataLine_7800, &entry)) {
+    if(checkCartSelection(myFile, &readDataLineMapperSize, &entry)) {
       EEPROM_writeAnything(7, entry.gameMapper);
       EEPROM_writeAnything(8, entry.gameSize);
     }
diff --git a/Cart_Reader/ARC.ino b/Cart_Reader/ARC.ino
index 28da27d..ed5a007 100644
--- a/Cart_Reader/ARC.ino
+++ b/Cart_Reader/ARC.ino
@@ -281,14 +281,6 @@ void checkStatus_ARC() {
 //******************************************
 // CART SELECT CODE
 //******************************************
-void readDataLine_ARC(FsFile& database, byte* gameSize) {
-  // Read rom size
-  (*gameSize) = database.read() - 48;
-
-  // Skip rest of line
-  database.seekCur(2);
-}
-
 void setCart_ARC() {
   //go to root
   sd.chdir();
@@ -302,7 +294,7 @@ void setCart_ARC() {
   if (myFile.open("arccart.txt", O_READ)) {
     // seek_first_letter_in_database(myFile, myLetter);
 
-    if(checkCartSelection(myFile, &readDataLine_ARC, &gameSize)) {
+    if(checkCartSelection(myFile, &readDataLineSingleDigit, &gameSize)) {
       EEPROM_writeAnything(8, gameSize);
     }
   } else {
diff --git a/Cart_Reader/C64.ino b/Cart_Reader/C64.ino
index 72c8940..eabe9dd 100644
--- a/Cart_Reader/C64.ino
+++ b/Cart_Reader/C64.ino
@@ -913,30 +913,12 @@ void printMapper_C64(byte c64maplabel) {
 //******************************************
 // CART SELECT CODE
 //******************************************
-struct database_entry_C64 {
-  byte gameMapper;
-  byte gameSize;
-};
-
-void readDataLine_C64(FsFile& database, struct database_entry_C64* entry) {
-  // Read mapper with two ascii character and subtract 48 to convert to decimal
-  entry->gameMapper = ((database.read() - 48) * 10) + (database.read() - 48);
-
-  // Skip over semicolon
-  database.seekCur(1);
-
-  // Read size and subtract 48 to convert to decimal
-  entry->gameSize = database.read() - 48;
-
-  // Skip rest of line
-  database.seekCur(2);
-}
 
 void setCart_C64() {
   //go to root
   sd.chdir();
 
-  struct database_entry_C64 entry;
+  struct database_entry_mapper_size entry;
 
   // Select starting letter
   byte myLetter = starting_letter();
@@ -945,7 +927,7 @@ void setCart_C64() {
   if (myFile.open("c64cart.txt", O_READ)) {
     seek_first_letter_in_database(myFile, myLetter);
 
-    if(checkCartSelection(myFile, &readDataLine_C64, &entry)) {
+    if(checkCartSelection(myFile, &readDataLineMapperSize, &entry)) {
       EEPROM_writeAnything(7, entry.gameMapper);
       EEPROM_writeAnything(8, entry.gameSize);
     }
diff --git a/Cart_Reader/COLV.ino b/Cart_Reader/COLV.ino
index a088c59..201e081 100644
--- a/Cart_Reader/COLV.ino
+++ b/Cart_Reader/COLV.ino
@@ -317,7 +317,8 @@ struct database_entry_COL {
   byte gameSize;
 };
 
-void readDataLine_COL(FsFile& database, struct database_entry_COL* entry) {
+void readDataLine_COL(FsFile& database, void* entry) {
+  struct database_entry_COL* castEntry = (database_entry_COL*)entry;
 
   // Read CRC32 checksum
   for (byte i = 0; i < 8; i++) {
@@ -329,7 +330,7 @@ void readDataLine_COL(FsFile& database, struct database_entry_COL* entry) {
 
   // Read CRC32 of first 512 bytes
   for (byte i = 0; i < 8; i++) {
-    entry->crc_search[i] = char(database.read());
+    castEntry->crc_search[i] = char(database.read());
   }
 
   // Skip over semicolon
@@ -337,15 +338,17 @@ void readDataLine_COL(FsFile& database, struct database_entry_COL* entry) {
 
   // Read rom size
   // Read the next ascii character and subtract 48 to convert to decimal
-  entry->gameSize = ((database.read() - 48) * 10) + (database.read() - 48);
+  castEntry->gameSize = ((database.read() - 48) * 10) + (database.read() - 48);
 
   // Skip rest of line
   database.seekCur(2);
 }
 
-void printDataLine_COL(struct database_entry_COL* entry) {
+void printDataLine_COL(void* entry) {
+  struct database_entry_COL* castEntry = (database_entry_COL*)entry;
+
   print_Msg(F("Size: "));
-  print_Msg(entry->gameSize);
+  print_Msg(castEntry->gameSize);
   println_Msg(F("KB"));
 }
 
diff --git a/Cart_Reader/Cart_Reader.ino b/Cart_Reader/Cart_Reader.ino
index a4b77f3..0d566af 100644
--- a/Cart_Reader/Cart_Reader.ino
+++ b/Cart_Reader/Cart_Reader.ino
@@ -681,6 +681,45 @@ void seek_first_letter_in_database(FsFile& database, byte myLetter) {
 #endif
 }
 
+#if (defined(ENABLE_ARC) || defined(ENABLE_FAIRCHILD) || defined(ENABLE_VECTREX))
+// 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))
+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
diff --git a/Cart_Reader/FAIRCHILD.ino b/Cart_Reader/FAIRCHILD.ino
index 5d372be..757f5f7 100644
--- a/Cart_Reader/FAIRCHILD.ino
+++ b/Cart_Reader/FAIRCHILD.ino
@@ -622,14 +622,6 @@ void checkStatus_FAIRCHILD() {
 //******************************************
 // CART SELECT CODE
 //******************************************
-void readDataLine_FAIRCHILD(FsFile& database, byte* gameSize) {
-  // Read rom size
-  (*gameSize) = database.read() - 48;
-
-  // Skip rest of line
-  database.seekCur(2);
-}
-
 void setCart_FAIRCHILD() {
   //go to root
   sd.chdir();
@@ -643,7 +635,7 @@ void setCart_FAIRCHILD() {
   if (myFile.open("fairchildcart.txt", O_READ)) {
     // seek_first_letter_in_database(myFile, myLetter);
 
-    if(checkCartSelection(myFile, &readDataLine_ARC, &gameSize)) {
+    if(checkCartSelection(myFile, &readDataLineSingleDigit, &gameSize)) {
       EEPROM_writeAnything(8, gameSize);
     }
   } else {
diff --git a/Cart_Reader/INTV.ino b/Cart_Reader/INTV.ino
index 492b196..383f272 100644
--- a/Cart_Reader/INTV.ino
+++ b/Cart_Reader/INTV.ino
@@ -641,8 +641,8 @@ struct database_entry_INTV {
   byte gameSize;
 };
 
-void readDataLine_INTV(FsFile& database, struct database_entry_INTV* entry) {
-
+void readDataLine_INTV(FsFile& database, void* entry) {
+  struct database_entry_INTV* castEntry = (database_entry_INTV*)entry;
   // Read CRC32 checksum
   for (byte i = 0; i < 8; i++) {
     checksumStr[i] = char(database.read());
@@ -653,21 +653,21 @@ void readDataLine_INTV(FsFile& database, struct database_entry_INTV* entry) {
 
   // Read CRC32 of first 512 bytes
   for (byte i = 0; i < 8; i++) {
-    entry->crc_search[i] = char(database.read());
+    castEntry->crc_search[i] = char(database.read());
   }
 
   // Skip over semicolon
   database.seekCur(1);
 
   // Read mapper
-  entry->gameMapper = database.read() - 48;
+  castEntry->gameMapper = database.read() - 48;
 
   // Skip over semicolon
   database.seekCur(1);
 
   // Read rom size
   // Read the next ascii character and subtract 48 to convert to decimal
-  entry->gameSize = ((database.read() - 48) * 10) + (database.read() - 48);
+  castEntry->gameSize = ((database.read() - 48) * 10) + (database.read() - 48);
 
   // Skip over semicolon
   database.seekCur(1);
@@ -679,12 +679,13 @@ void readDataLine_INTV(FsFile& database, struct database_entry_INTV* entry) {
   database.seekCur(2);
 }
 
-void printDataLine_INTV(struct database_entry_INTV* entry) {
+void printDataLine_INTV(void* entry) {
+  struct database_entry_INTV* castEntry = (database_entry_INTV*)entry;
   print_Msg(F("Size: "));
-  print_Msg(entry->gameSize);
+  print_Msg(castEntry->gameSize);
   println_Msg(F("KB"));
   print_Msg(F("Mapper: "));
-  println_Msg(entry->gameMapper);
+  println_Msg(castEntry->gameMapper);
 }
 
 void setCart_INTV() {
diff --git a/Cart_Reader/MSX.ino b/Cart_Reader/MSX.ino
index ea78d0f..e39eb54 100644
--- a/Cart_Reader/MSX.ino
+++ b/Cart_Reader/MSX.ino
@@ -1281,21 +1281,22 @@ struct database_entry_MSX {
   byte ramSize;
 };
 
-void readDataLine_MSX(FsFile& database, struct database_entry_MSX* entry) {
+void readDataLine_MSX(FsFile& database, void* entry) {
+  database_entry_MSX* castEntry = (database_entry_MSX*)entry;
   // Read mapper
-  entry->gameMapper = ((database.read() - 48) * 10) + (database.read() - 48);
+  castEntry->gameMapper = ((database.read() - 48) * 10) + (database.read() - 48);
 
   // Skip over semicolon
   database.seekCur(1);
 
   // Read rom size
-  entry->gameSize = database.read() - 48;
+  castEntry->gameSize = database.read() - 48;
 
   // Skip over semicolon
   database.seekCur(1);
 
   // Read ram size
-  entry->ramSize = database.read() - 48;
+  castEntry->ramSize = database.read() - 48;
 
   // Skip rest of line
   database.seekCur(2);
diff --git a/Cart_Reader/NES.ino b/Cart_Reader/NES.ino
index 6f4f757..1865ef3 100644
--- a/Cart_Reader/NES.ino
+++ b/Cart_Reader/NES.ino
@@ -511,12 +511,13 @@ void setRomnameFromString(const char* input) {
   }
 }
 
-void printDataLine_NES(struct database_entry* entry) {
+void printDataLine_NES(void* entry) {
+  struct database_entry* castEntry = (struct database_entry*) entry;
   uint8_t iNES[16];
   uint8_t* output;
   char* input;    
 
-  input = entry->iNES_str;
+  input = castEntry->iNES_str;
   output = iNES;
   for (uint8_t i = 0; i < sizeof(iNES); i++) {
     unsigned int buf;
@@ -670,7 +671,8 @@ static void readDatabaseEntry(FsFile& database, struct database_entry* entry) {
   skip_line(&database);
 }
 
-void readDataLine_NES(FsFile& database, struct database_entry* entry) {
+void readDataLine_NES(FsFile& database, void* e) {
+  struct database_entry* entry = (database_entry*)e;
   get_line(entry->crc_str, &database, sizeof(entry->crc_str));
 
   entry->crc_str[8] = 0;
diff --git a/Cart_Reader/ODY2.ino b/Cart_Reader/ODY2.ino
index 7388861..aaf7fcf 100644
--- a/Cart_Reader/ODY2.ino
+++ b/Cart_Reader/ODY2.ino
@@ -369,30 +369,11 @@ void checkStatus_ODY2() {
 //******************************************
 // CART SELECT CODE
 //******************************************
-struct database_entry_ODY2 {
-  byte gameMapper;
-  byte gameSize;
-};
-
-void readDataLine_ODY2(FsFile& database, struct database_entry_ODY2* entry) {
-  // Read mapper
-  entry->gameMapper = database.read() - 48;
-
-  // Skip over semicolon
-  database.seekCur(1);
-
-  // Read rom size
-  entry->gameSize = database.read() - 48;
-
-  // Skip rest of line
-  database.seekCur(2);
-}
-
 void setCart_ODY2() {
   //go to root
   sd.chdir();
 
-  struct database_entry_ODY2 entry;
+  struct database_entry_mapper_size entry;
 
   // Select starting letter
   byte myLetter = starting_letter();
@@ -401,7 +382,7 @@ void setCart_ODY2() {
   if (myFile.open("ody2cart.txt", O_READ)) {
     seek_first_letter_in_database(myFile, myLetter);
 
-    if(checkCartSelection(myFile, &readDataLine_ODY2, &entry)) {
+    if(checkCartSelection(myFile, &readDataLineMapperSize, &entry)) {
       EEPROM_writeAnything(7, entry.gameMapper);
       EEPROM_writeAnything(8, entry.gameSize);
     }
diff --git a/Cart_Reader/VECTREX.ino b/Cart_Reader/VECTREX.ino
index b997a18..4df8110 100644
--- a/Cart_Reader/VECTREX.ino
+++ b/Cart_Reader/VECTREX.ino
@@ -340,14 +340,6 @@ void checkStatus_VECTREX() {
 //******************************************
 // CART SELECT CODE
 //******************************************
-void readDataLine_VECTREX(FsFile& database, byte* gameSize) {
-  // Read rom size
-  (*gameSize) = database.read() - 48;
-
-  // Skip rest of line
-  database.seekCur(2);
-}
-
 void setCart_VECTREX() {
   //go to root
   sd.chdir();
@@ -361,7 +353,7 @@ void setCart_VECTREX() {
   if (myFile.open("vectrexcart.txt", O_READ)) {
     // seek_first_letter_in_database(myFile, myLetter);
 
-    if(checkCartSelection(myFile, &readDataLine_ARC, &gameSize)) {
+    if(checkCartSelection(myFile, &readDataLineSingleDigit, &gameSize)) {
       EEPROM_writeAnything(8, gameSize);
     }
   } else {
diff --git a/Cart_Reader/WSV.ino b/Cart_Reader/WSV.ino
index c48cb16..e4e997a 100644
--- a/Cart_Reader/WSV.ino
+++ b/Cart_Reader/WSV.ino
@@ -330,8 +330,8 @@ struct database_entry_WSV {
   byte gameSize;
 };
 
-void readDataLine_WSV(FsFile& database, struct database_entry_WSV* entry) {
-
+void readDataLine_WSV(FsFile& database, void* entry) {
+  struct database_entry_WSV* castEntry = (database_entry_WSV*)entry;
   // Read CRC32 checksum
   for (byte i = 0; i < 8; i++) {
     checksumStr[i] = char(database.read());
@@ -342,7 +342,7 @@ void readDataLine_WSV(FsFile& database, struct database_entry_WSV* entry) {
 
   // Read CRC32 of first 512 bytes
   for (byte i = 0; i < 8; i++) {
-    entry->crc_search[i] = char(database.read());
+    castEntry->crc_search[i] = char(database.read());
   }
 
   // Skip over semicolon
@@ -350,18 +350,19 @@ void readDataLine_WSV(FsFile& database, struct database_entry_WSV* entry) {
 
   // Read rom size
   // Read the next ascii character and subtract 48 to convert to decimal
-  entry->gameSize = ((database.read() - 48) * 10) + (database.read() - 48);
+  castEntry->gameSize = ((database.read() - 48) * 10) + (database.read() - 48);
 
   // Skip rest of line
   database.seekCur(2);
 }
 
-void printDataLine_WSV(struct database_entry_WSV* entry) {
+void printDataLine_WSV(void* entry) {
+  struct database_entry_WSV* castEntry = (database_entry_WSV*)entry;
   print_Msg(F("Size: "));
-  if (entry->gameSize == 51)
+  if (castEntry->gameSize == 51)
     print_Msg(F("512"));
   else
-    print_Msg(entry->gameSize);
+    print_Msg(castEntry->gameSize);
   println_Msg(F("KB"));
 }