User guide

August 2001 119
Handling Incoming and Outgoing Calls
Terminating an Inbound Call
Terminate calls using RHT_ON_HOOK or
RHT_DISCONNECT. These functions are interchangeable, so
all discussion of RHT_DISCONNECT also applies to
RHT_ON_HOOK.
RHT_DISCONNECT transmits a disconnect (idle) pattern for
the time specified by RDG_LOCAL_IDLE_DUR. It then waits
for the remote end to disconnect for a time specified by
RDG_REMOTE_IDLE_TIMEOUT. After it receives the
disconnect, RHT_DISCONNECT waits for a time specified by
RDG_LOCAL_IDLE_GUARD_TIME then returns. Table 24
shows the sequence involved in terminating a call.
Table 24. RHT_DISCONNECT Sequence
In the R2 CCITT protocol, the protocol sends a Clear Back
disconnect signal to terminate incoming calls. Outgoing calls
terminate using a Clear Forward signal.
If the remote end disconnects first and your application calls
RHT_DISCONNECT in response to their disconnect signal, it
returns almost immediately. The only delays are those caused
by RDG_LOCAL_IDLE_DUR and
RDG_LOCAL_IDLE_GUARD_TIME.
The remote end only sends an idle pattern when the calling
party hangs up. If the caller does not know that your application
has disconnected, it might take a while for them to hang up. An
application should play a busy signal when it hangs up so the
calling party knows you have disconnected.
Action Duration
Transmit disconnect RDG_LOCAL_IDLE_DUR
Wait for disconnect RDG_REMOTE_IDLE_TIMEOUT
Wait RDG_LOCAL_IDLE_GUARD_TIME
Return