Cisco VG224 hookflash transfer

[digiteltlc (digitel)]

I succesfully registered few VG224 FXS ports as Freepbx extensions.
No trunk between VG224 and freepbx, simply a sip (pjsip) registration from VG224 voice port.
Does anyone know if call transfer via hookflash is possible ?
I set the correct hookflash timing but nothing happens when hookflash is received by fxs port.
Maybe I’m expecting something not possible by working principle…

*2 is a solution but…

[kenn10]

@digiteltlc

VG224

According to Cisco documentation, you need to have the Max Calls = 2 in order to make this work.

[digiteltlc (digitel)]

From what I understood “max calls” is a pbx-side command (UC)

I got transfer working with

application
service dsapp
param callWaiting TRUE
param callTransfer TRUE
!
global
service default dsapp

on VG224 side.