I'm trying to 'share' a buzzer between 2 separate mcu's, one is on a multirotor flight controller (STM32 or Atmega328), the other is a module I'm adding that needs to use the same buzzer.
diagram: left side is flight controller (cannot change), right side is my module simplified.
The issue I'm having is that the buzzer driver circuit varies on flight controllers, some use a low-side switch (see diagram), but some use a high-side switch. I'm trying to come up with a solution that will work in both situations, which I think means I need to supply my own v+ and gnd to the buzzer.
Can anyone refine my circuit (I'm not sure it would work), or offer something better?
thanks!