Let's say you want to change the configuration for the extension 1234
go to load 2 : ld 20
REQ CHG
TYPE 500 (type of the telephone 2002p2, 2004p2...etc)
TN XXX X XX XX (TN of the telephone)
ECHG YES
ITEM : fdn 1234
ITEM : hunt 1234
<enter> for the rest
What it does, when the user 1234 is on the phone, it will tried to ring again on his phone, which will give a busy tone.
When the user is not there, the phone will ring non-stop till the caller hangup.
Hope that's helps
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