99% of initial problems with circuit playground are due to having charge USB cables instead of sync cables. Do not use a cable you've only used for charging a phone. Make sure its a cable that can pass data as well as power. Lately, there's been a lot of products shipped with charging only cables and it's very confusing because the Circuit Playground lights up but does not show up in the Arduino IDE!
So, please, try multiple USB cables, and if you find a charge-only cable, cut it in half and throw it away so you will not make the mistake again!
No problem! You can 'repair' a bad code upload easily. Note that this can happen if you set a watchdog timer or sleep mode that stops USB, or any sketch that 'crashes' your Circuit Playground
- Turn on verbose upload in the Arduino IDE preferences
- Plug in Circuit Playground, it won't show up as a COM/serial port that's ok
- Open up the Blink example (Examples->Basics->Blink)
- Select the correct board in the Tools menu, e.g. Circuit Playground (make sure you select the correct board)
- Compile it (make sure that works)
- Click Upload to attempt to upload the code
- The IDE will print out a bunch of COM Ports as it tries to upload. During this time, double click the reset button, you'll see the red pulsing LED that tells you its now in bootloading mode
- The Cplay will show up as the Bootloader COM/Serial port
- The IDE should see the bootloader COM/Serial port and upload properly
This seems to happen when people select the wrong board from the Arduino Boards menu. Make sure you select Circuit Playground! Do not use anything else, do not use the 32u4 breakout board line.
Use the 'repair' technique above to fix it.