Motorola g20 Developer's Manual page 85

Table 22. +CHLD Actions According to Call State and Operation (Continued)
Call State
0 -Release
Held Call
Split: Places the active MTPY call on hold, except for a specific call x.
Switch: Places the active call on hold and accepts the Held call
Error 3: "Operation not allowed"
Error 22: "Not found"
Example
at+chld=?
+CHLD: (0, 1, 1x, 2, 2x, 3)
OK
at+ccwa=1
OK
atd9311234567;
OK
CONNECT
(...conversation...)
+CCWA: "+358317654321",145,1,"Bob" //Awaiting call alerts
at+chld=2
OK
(...conversation...)
at+chld=3
OK
(...MTPY conversation...)
at+chld=22
OK
at+chld=0
OK
NO CARRIER
ath
NO CARRIER
OK
98-08901C68-O
CHLD <operation>
1 - Release 1x - Release
Active Call, Active Call x
Accept Held from MTPY
Call Call
//Enable call waiting
//Originate a voice call
//Put first call on hold and answer the second call
//Add the held call to the conversation
//Split: Place the MO active call on hold, MT call remains active
//Release the held call
//Release the active call
AT Commands Reference
2x - Active
2 - Switch
MTPY Call
Between
to Hold,
Held and
Except for
Active Call
Call x
3 - Add
Held Call to
Active Call
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