Siemens TC63 - Manual (Page 223)

TC63 AT Command Set
9.8 AT+CHLD
s
TC63_ATC_V00.490 Page 223 of 501 5/24/05
Confidential / Draft - Do not copy
Notes
• The
AT+CHLD
command offers a broad range of options according to the GSM specifications. However, if you
attempt to invoke an option which is not provisioned by the network, or not subscribed to, invocation of this
option will fail. The responses in these cases may vary with the network (for example "Operation not allowed",
"Operation not supported" etc.).
• The handling of the supplementary service Call hold and Multiparty varies with the types of calls. This is
because only voice calls can be put on hold, while data or fax calls cannot. The following procedures apply:
With
AT+CHLD
=2 the user can simultaneously place a voice call on hold and accept another waiting voice,
data or fax call. If the waiting call is a data or fax call, it is also possible to put the voice call on hold. To switch
back from the active data or fax call to the held voice call the active call must be terminated with
AT+CHLD
=1.
If all active and held calls are voice calls it is possible to switch back and forth with
AT+CHLD
=2.
• In conflict situations, e.g. when a waiting call comes while there are already held calls, the above procedures
apply to the waiting call only. For example,
<n>
=0 rejects the waiting call, but does not affect the held calls.
• See also the
AT+CCWA
command for details on how to display waiting calls.
Example
^SYSSTART
at+cpin="9999"
OK
+CREG: 2
+CREG: 1,"0145","0016"
The mobile is now registered.
at+ccwa=1,1,1
You activate the indication of waiting calls during
voice calls.
OK
atd"1234567";
You make a voice call.
OK
+CCWA: "+491791292364",145,32,,0
You receive a URC indicating a waiting data call.
at+chld=2
You put the voice call on hold.
CONNECT 9600/RLP
The data connection is set up.
hello
+++
With ''+++'' you go in command mode.
OK
at+clcc
You interrogate the status of all established calls.
+CLCC: 1,0,1,0,0,"03038639268",129
+CLCC: 2,1,0,1,0,"+491791292364",145
OK
at+chld=1
The active data call is terminated and the held voice
call becomes active.
OK
at+clcc
+CLCC: 1,0,0,0,0,"03038639268",129
OK