Does the ambulance siren control also need to regulate the strobe light?

The strobe light feature may not be used in your country...but here in the USA many cities have strobe lights mounted on emergency vehicles (ambulance, police car, or fire engine) that pulses on and off with a very specific high speed variable cadence flashing sequence. This strobe is detected at the upcoming intersections to switch the traffic lights automatically. Some systems switch the lights to green for the direction the emergency vehicle is approaching and other systems just put the whole intersection into four way flashing red.

I bring this up because of the strobe system is in use in your intended market this could be a very nice extra feature or option to add to your product that can be easily controlled by the microcontroller. (And of course it is active all the while the siren is in use!!!).

Michael Karas