  */
 char toHexLow( uint8_t h ) {
   h = h & 0x0f;
-  if( h > 9) return 'A' + (h-9);
+  if( h > 9) return 'A' + (h-10);
 
   return '0' + h;
 }

 */
char toHexHigh( uint8_t h ) {
  h = h>>4;
  if( h > 9) return 'A' + (h-10);

  return '0' + h;
}
