2 Button to 1 PWM output

There are only 2 buttons, it is no rocket science.

I only need a pwm singal on pin outlet 11

I'm really sorry that I don't post everything like is has to be

so when the switch is low i need 5v pwm
when the switch is high i need 2.5v pwm
if the button is pushed i always need 0v pwm (with timer).

Im just frustrated that it won't work.