Let's upload your "Hello World" app to your robot to see if it works.
Your RedBot kit should have a USB to Mini-USB cable that allows you to connect the robot to a computer, in order to update the robot's app (or to send serial data to the computer).
Carefully plug the small end of this cable into the Mini-USB port on your RedBot circuit board. Plug the other end of the cable into a USB port on your computer.
IMPORTANT: Stand the RedBot upright on its back end (so its wheels are in the air). This is a precaution to make sure your robot doesn't drive away while connected to your computer.
Your RedBot is powered by a battery pack containing 4 AA batteries. Be sure the battery pack cable is plugged into the barrel jack on your RedBot circuit board.
Slide the RedBot's Power switch to ON. The RedBot's green Power LED light should turn on.
STOP MOTORS: If your robot's wheels start spinning when powered on (because the robot is running an existing app), you can temporarily slide the Motor switch to STOP if desired.
NO POWER: If the robot's Power LED doesn't turn on, verify the battery pack cable is plugged in and the Power switch is set to ON. Next, try replacing the AA batteries in the battery pack.
In order to upload your app to your robot, the code editor must know which type of Arduino board your robot has and which USB port on your computer that the robot is connected to.
If you previously selected your Arduino board type (which should be "Arduino/Genuino Uno"), the code editor should remember this selection.
Click "Select Other Board & Port" in the drop down menu at the top of the code editor panel.
In the pop-up, verify that "Arduino/Genuino Uno" is selected, and then select the correct USB port that your robot is connected to. Finally, click the OK button.
On Mac, the correct port should include "usbserial" as part of its name.
On Windows, there should be one or more numbered COM ports listed. You may have to select one, try uploading your app — and then if the app won't upload, switch to another COM port instead until you identify the correct port.
Under the Tools menu, verify that "Arduino/Genuino" is selected in the Board sub-menu, and then select the correct USB port in the Port sub-menu:
On Mac, the correct port should include "usbserial" as part of its name.
On Windows, there should be one or more numbered COM ports listed. You may have to select one, try uploading your app — and then if the app won't upload, switch to another COM port instead until you identify the correct port.
Once you've selected the correct port, the code editor should remember this selection while you keep the code editor open. However, if you close the code editor, you'll have to select the correct port again the next time you open and use the code editor.
Click the Upload icon (looks like a right arrow) at the top of the code editor panel. The code editor will automatically save and verify the app before uploading it to your robot.
During the upload process, you may notice two other green LED lights (labeled TX and RX, located next to the Mini USB port) blinking rapidly as the app code is transferred to the robot.
Once the upload is complete, the new app will immediately start running on your robot.
UPLOAD ERROR: If the Arduino code editor indicates there was a problem uploading to the board, it most likely means that the correct port was not selected. Be sure the correct USB port is selected in the code editor.
Confirm that the built-in green D13 LED light blinks on and off in a repeating pattern (changing every 0.5 second).
Arduino devices, such as the RedBot, can only store and run one app at a time. If you want to change the app running on your robot, you have to upload a different app from your code editor to the robot.
Next, try modifying the code within the loop() function to make the LED blink faster (Hint: use shorter delays).
Upload your modified app to your robot to see if your changes worked as you expected.
Then modify the code to make the LED blink slower. Then upload your modified app to your robot to see if it works.