So I have two programs that are meant to talk to radio's via GPIO pins but need them to talk to each other via GPIO

Eg..

Program 1
PTT = 12
COS = 16

Program 2
PTT = 16
COS = 12

So basicly when **Program 1** keys up its sets Pin 12 high then **Program 2** see's pin 12 is high and triggers it.

I get an error saying the device is busy tho when I do it like this.

Any other ideas as they both talk on GPIO pins

Thanks
Sonic