SPA942 as a public address system


I’m using Linksys SPA942’s and an Asterisk PBX. I’d like to introduce some sort public address system, meaning that a receptionist can dial a certain number and that this number dials all phones, makes them accept the call and be switched to handsfree mode so the recpetionist can do urgent announcements.

Would this be possible, even with some programming (CURL and URL manipulation for instance)?

Thank you,