How to make a HID bluetooth device (keyboard) on STM32f4?

Question

Bluetooth

Hello. I want to make a wireless bluetooth keyboard on STM32f4. Bluetooth module launched (found the project), but it works as a COM port. How to make or where to read, what would Windows define it as a HID device - a keyboard. There are also wireless mice and keyboards that simply connect via bluetooth and work immediately, but I could not find information on this.

Answer 1

With difficulty, I found the answer. And simple to disgrace - there should be only one firmware with HID. Already looked for this.
1 - is on sale, but at a price of 30-40 dollars.
2 - flash it yourself, after writing the firmware or find the firmware on the Internet.

Answer 2

I suspect that nothing will come of this option if your module works as a UART <-> bluetooth adapter, and not as a "modem" that understands AT commands and can "pretend" with different devices.
If so, then at the reception you need to install the same UART<->bluetooth and a simple MK with USB (say, STM32F042), which will already be configured as a keyboard and will spit out the received signals into USB.
As a result, the computer will "think" that a regular USB keyboard is connected to it.
By the way, this method is also good because the block plugged into the computer can be made a composite device, set up udev to launch a self-written daemon when this "keyboard" is connected, and log everything that was entered from the keyboard.