   // so you have to close this one before opening another.
   myFile = SD.open(fileName, FILE_READ);
   
-  // if the file opened okay, write to it:
+  // if the file opened okay, read from it:
   if (myFile) {
     // Initialize a string buffer to read lines from the file into
     // Allocate an extra char at the end to add null terminator

    Serial.println("initialization failed!");
  }
  Serial.println("initialization done.");
  SelectMap(Origin,"map_defs.txt");
  
     ConstructNetwork(Nodes, map_points);
     




#define MAX_MAPS 16         // The maximum number of map files stored to SD card.
#define MAX_WAYPOINTS 16    // The maximum number of waypoints in each map file.
/*   There are two coordinate systems.
     MDF and RNDF use latitude and longitude.
     C3 and C6 assume that the earth is flat at the scale that they deal with
