I have an electronic system waiting to be triggered (no microcontroller for now). My laptop only has USB ports.
I want to trigger it using voice recognition (this part is ok).
For now the only think I can think of is :
Once the right keyword is detected, send a 19 KHz sine on the audio output, because it's inaudible, for 0.1 seconds and uses a microcontroller analog port to detect it.
I only have microcontroller with no USB support available and I've never used a USB connection.
I'm not looking for something perfect, a dirty solution would be all right, this is just to do a prank tomorrow.