i tried the same for a long time and had no sucess. when i had asterisk running on my raspberry, at least i was not able to execute commands due to user right issues…so i gave it up, but really would be interesstet if someone could share a running example with the code.
so i restarted this project with an arduino, and a bit of c++ code - compiled this via visual studio to the arduino. now i’m able to send a mqtt message to the arduino, and because it’s a sip client on the fritzbox, it makes the call. cool but not perfect, because it requires an additional bit of hardware.
the fritzbox binding itself is not able to do calls.
(Stuart Hanlon, UK importer of Velbus hardware)
I’ve got a FritzBox Fon too and have been pondering something like this for ages.
But alas, no solution yet, as I just don’t have the programming skills.
It looks like sip browser plugins don’t work, but I did have some luck with a Tapi solution years ago with another project, is that an angle to look at?