Please use code tags (</> button on the toolbar) when you post code or warning/error messages. The reason is that the forum software can interpret parts of your code as markup, leading to confusion, wasted time, and a reduced chance for you to get help with your problem. This will also make it easier to read your code and to copy it to the IDE or editor. If your browser doesn't show the posting toolbar then you can just manually add the code tags:
[code]``[color=blue]// your code is here[/color]``[/code]
Using code tags and other important information is explained in the How to use this forum post. Please read it.
Please always do a Tools > Auto Format on your code before posting it. This will make it easier for you to spot bugs and make it easier for us to read. If you're using the Arduino Web Editor you will not have access to this useful tool but it's still unacceptable to post poorly formatted code. I recommend you to use the standard IDE instead.
Select the port of your Arduino from the Tools > Port menu. If that menu is grayed out or the port of your Arduino board is not shown then one of the following may be the cause:
- You may need to install the driver for the USB-serial chip on your Arduino. Determine which chip is used on your Arduino and install the driver.
- You may be using a charge-only or defective USB cable. Test your cable on another device to confirm that it works for data.