Reply To: Error setting Hydros21 address

When you’re connected to the Mayfly with your computer, open the Arduino IDE’s Serial Monitor and check the settings of the dropdown box in the lower right hand part of the windows next to the baud rate.  It should be set to “No line ending”.  If you have it set to anything else, you’ll usually get an error when setting the address using that sketch because you’re sending it the address character AND a line ending or carriage return.  Saying “No line ending” should fix it.