Arduino Leonardo Upload Differences

by Visual Micro 2. June 2012 08:15

The Arduino Leonardo is a usb device that works in a different way to older or existing Arduino hardware. When a Leonardo starts it breifly appears in programming mode on a different serial port to the one it normally uses.

When an Arduino upload request begins the specified Leonardo serial port is polled at 1200 baud causing the Leonardo to reset. If the port is not found, both the Arduino and Visual Studio IDEs assume that the Leonardo has been reset or was resetting/starting and skip the attempt to reset.

Both Visual Studio and the Arduino IDE, scan to detect the new programming port appearing in the computers serial ports list which indicates a Leonardo startup has been detected. If a new port is not detected then both IDEs' will wait for 5 seconds (on windows) before raising the error:- "Couldn’t find a Leonardo on the selected port. Check that you have the correct port selected. If it is correct, try pressing the board's reset button after initiating the upload."

On Microsoft windows, once the upload has completed, there is a 0.5 sec pause to ensure the Leonardo has re-booted and that the original serial port has re-connected.

After upload, Visual Studio confirms the actual upload port to the user using the "Sketch Output" tab. An example Leonardo upload message is shown below. Notice the switch from Leonardo serial COM37 to COM38

Compiling 'MySensor' for 'Arduino Leonardo'

Binary sketch size: 4844 bytes (of a 28672 byte maximum) (0.507 secs)

Uploading to I/O board using 'COM37'

Done uploading via 'COM38'

 

This document is a result of reading the source code for the arduino ide provided by arduino.cc

Arduino Leonardo - Windows Hardware USB Installation Guide

by Visual Micro 2. June 2012 05:43

Windows (tested on XP and 7)

The process for Windows XP and Windows 7 is similar. These screenshots are from an XP installation.

  • Plug in your board and wait for Windows to begin its driver installation process. If the installer does not launch automatically, Navigate to the Windows Device Manager (Start>Control Panel>Hardware) and find the Arduino Leonardo listing. Right click and choose Update driver.
  • If prompted to search for drivers online, choose "No, not this time". And click Next

Arduino Leonardo Windows Driver Installation - 1

  • When asked to install automatically or from a specific location, select "Install from a list or specific location" and press Next
Arduino Leonardo Windows Driver Installation - 2
  • Choose "Search for the best driver in these locations", and check the box "incude this location in the search". Click the Browse button and navigate to your Arduino 1.0.1 or later installation. Select the drivers folder an click OK
Arduino Leonardo Windows Driver Installation - 3
  • Click Next
  • You will receive a notification that the Leonardo has not passed Windows Logo testing. Click on the button Continue Anyway
Arduino Leonardo Windows Driver Installation - 4
  • After a few moments, a window will tell you the wizard has finished installing software for Arduino Leonardo. Press the Finish button

Original article found on arduino.cc