Is there a way to read the state of the computer? (HID Keyboard)

[JMOON.1]

I'm using 'STM32F103RCT' and been create a HID Custom keyboard.

I want to know the states of 'Num Lock', 'Insert' and 'Caps Lock' etc on the HID keyboard's computer.

Because it has to be checked with LED.

lighting the LED is essential when connecting to the computer.

How do I know the state of the computer?

Reading the computer's state is the difficult problem.

[Pavel A. · Accepted solution]

A keyboard does not "read" the host's (computer) Num lock etc. states.

Rather, the computer requests the keyboard to set its LEDs on/off.

The keyboard should advertise the LEDs capability in its HID report descriptor and should handle the host's requests properly.

-- pa