bugfix about SDCARD ERROR if no folder on FAT system for models

folder will be created now
if no model name assigned then an "MODELXX" hardcoded string used as name

src/eeprom_avr.cpp

@@ -531,6 +531,7 @@ const pm_char * eeArchiveModel(uint8_t i_fileSrc)
 {
   char *buf = reusableBuffer.model_name;
   FIL archiveFile;
+  DIR archiveFolder;
   UINT written;
 
   FRESULT result = f_mount(0, &g_FATFS_Obj);
@@ -541,6 +542,9 @@ const pm_char * eeArchiveModel(uint8_t i_fileSrc)
   strcpy_P(buf, PSTR(MODELS_PATH "/")); // TODO Not PSTR everywhere ...
 
   eeLoadModelName(i_fileSrc, &buf[sizeof(MODELS_PATH)]);
+	if(buf[sizeof(MODELS_PATH)] == '\0'){//no model name loaded
+		strcpy_P(&buf[sizeof(MODELS_PATH)], PSTR("\x0d\x0f\x04\x05\x0c\x18\x18"));//temporary fix as "MODELXX", itoa(i_fileSrc-1) need to be appended
+	}		
   buf[sizeof(MODELS_PATH)+sizeof(g_model.name)] = '\0';
 
   uint8_t i = sizeof(MODELS_PATH)+sizeof(g_model.name)-1;
@@ -554,6 +558,22 @@ const pm_char * eeArchiveModel(uint8_t i_fileSrc)
   }
   strcpy_P(&buf[len], PSTR(".bin")); // TODO Not PSTR everywhere ...
 
+  //check and create folder here
+  //temporary truncate for folder name only
+  buf[sizeof(MODELS_PATH)-1] = '\0';
+  
+  result = f_opendir(&archiveFolder, buf);
+  if(result != FR_OK){
+	  result = f_mkdir(buf);
+	  if(result != FR_OK){
+		  return SDCARD_ERROR(result);
+	  }		  
+  }
+  
+  //return back / char to get full model name
+  buf[sizeof(MODELS_PATH)-1] = '/';
+  //folder ready to write here
+
   result = f_open(&archiveFile, buf, FA_OPEN_ALWAYS | FA_WRITE);
   if (result != FR_OK) {
     return SDCARD_ERROR(result);