1.1: Connecting and Coding with Blockly

Blockly is an online application that you can access right from Google Chrome. You can go to it by heading to this url: robolink.com/blockly-cde.  With Blockly, you can connect it to your drone as well as program it in two modes:

• Junior: Simplified block-based coding for beginners
• Senior: For intermediate coders who have some familiarity with block coding

There is no need to install anything since Blockly runs only in the browser!

Your Google Chrome should be updated to the most recent version. If you are not sure how to check, click on the the menu on the top right, scroll down to “Help”, and select “About Google Chrome”. Google Chrome might automatically update. If not, please update Chrome.

Try to use the cable that comes with CoDrone EDU whenever possible! This Micro USB cable can transfer data, which is necessary for programming. Most Micro USB cables now are data compatible. If your drone does not switch to LINK state when connecting, you may have the wrong cable or it may be broken.

Next, power on the drone using a charged battery.

Your drone should pair to the controller, as indicated by the solid LED on the drone and controller. If your drone and controller are not paired, watch this video.

Once your controller is connected, click on the green “Connect” button on the bottom left of the screen. Then select the option from the drop-down menu. If you don’t see anything in the menu, check that your controller is in “LINK” state or use a different cable.

If you are still having trouble with connecting to Blockly, please read this article for help: Help! Blockly is not connecting to my CoDrone EDU controller!

Selecting a block

To write your code, drag blocks from the menus on the left to the workspace in the middle of the page. Try dragging a takeoff block from the flight commands menu.

Connecting blocks

Connect a second block by dragging the block underneath the previous one until you see the yellow outline.

* Click! *

Deleting a block

There are two ways to delete a block. The first way is to separate what you want to get rid of from your code and drag them to the trashcan in the lower righthand corner. To delete the entire program, you can drag all blocks at once to the trashcan.

You can also delete a block by dragging it to the lefthand side and dropping it in the menu.

If you have used other visual programming interfaces before, you may be familiar with a “when play clicked” block similar to the one below.

Any blocks connected to this block will run when you click the “play” button.

Any blocks that are not connected to the “when play clicked” block will be automatically disabled.

Using this block is a useful feature if you want to quickly switch between multiple programs in your workspace.

Note: Using this block is optional. If you want to delete the block, Blockly will have to reload the page and you will need to pair your drone again.

Lessons

Select the “Lessons” tab on the righthand side of Blockly to access the lessons. Now you can see your code and the tutorial at the same time!

Python example

Select the “Python” tab from the righthand side of Blockly to see what your block code would look like in Python. You can’t write any code in Python on the web just yet, but you can get a preview of Python coding and familiarize yourself with the language.

When you are ready to run your program, place your drone on the floor in an open area. Keep your drone controller connected to the computer. Then, click on “Run” on the upper lefthand side of your workspace.