DTMF tones for programming and release feature

[vad]

When you call the emergency phone and phone answer - you need PREFIX (f.e. *, external feature, end-to-end dialing). Not use suffix in this case.
Call phone, when phone answer press"*", you will see "DTMF" on display, now you can enter code for emergency set.

[jbower]

Got it to work thanks guys.