Motorola g20 Developer's Manual page 82

AT Commands Reference
at+chld=0
OK
NO CARRIER
at+crc=1
OK
(...waiting call..., caller restricted to its CLI presentation (used at+clir)...)
+CCWA: "",128,1,"",1
4.3.3.9 +CHLD, Call Related Supplementary Services Command
This command controls the Call Hold and Multiparty Conversation services. This command manipulates voice calls only.
Set Command
The Set command allows the control of the following call related services:
• Call HOLD: A call can be temporarily disconnected from the g20, but the connection is retained by the network.
• MTPY (Multi party) Conversation: Conference calls.
The network does not reserve more than one traffic channel for a mobile station, therefore the g20 can have only one call on
hold at a time.
Only voice calls can be put on HOLD.
A precondition for the multi-party service is that the g20 is in control of one active call and one call on hold. In this
situation, the g20 can request the network to begin the MTPY (Multi Party) service. Once a MTPY call is active,
Note
remote parties may be added, disconnected or separated (removed from the MTPY call, but remain connected to
the served mobile subscriber).The maximum number of remote parties is 5.
In this command, the term CALL refers to a single or MTPY call.
A single Active call is considered an MTPY call with one call index numbered as 1.
Command
+CHLD=<n>
68
//Release the waiting call
//RING indication is not relevant to CCWA indication
//CLI is restricted, but call type recognized as voice+CCWA: "",128,1,"",1
Response/Action
If the call is terminated:
OK (approve request was submitted)
NO CARRIER
If the call state is changed (link, split, from active to
hold, and so on):
OK (approve request was done)
If the call is terminated and another call is answered:
OK (approve request was submitted)
NO CARRIER
OK (call answered and is now connected)
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