Hello users of the 32u4-A9G, to use this module with the Arduino IDE, you can select the Arduino Leonardo card, it uses an ATmega32u4 identical to that of the A9G card.
Then you can take inspiration from the codes of the Hackaday website: Results for A9G | Hackaday.io.
I translated AI-Thiker's A9G datasheet from Chinese to French, but it's easily retranslatable into English for those interested.
The most important thing in using this product is that for it to work well you have to wait for the A9G to start (several seconds) the best is to test your code with a command AT.
Good debug!
Vincent.
