SimCom SIM7600 Series User Manual

Smart Machine Smart Decision
SIM7500_SIM7600 Series_AT Command Manual_V1.07 2017-12-25
120
This command allows the control the following call related services:
1. A call can be temporarily disconnected from the ME but the connection is retained by the
network.
2. Multiparty conversation (conference calls).
3. The served subscriber who has two calls (one held and the other either active or alerting)
can connect the other parties and release the served subscriber's own connection.
Calls can be put on hold, recovered, released, added to conversation, and transferred. This is
based on the GSM/UMTS supplementary services.
SIM PIN References
YES 3GPP TS 27.007
Syntax
Test Command Responses
AT+CHLD=?
+CHLD: (list of supported <n>s)
OK
Write Command Responses
AT+CHLD=<n> OK
ERROR
+CME ERROR: <err>
Execution Command
Responses
AT+CHLD
Default to <n>=2.
OK
ERROR
+CME ERROR: <err>
Defined values
<n>
0 – Terminate all held calls; or set User Determined User Busy for a waiting call
1 – Terminate all active calls and accept the other call (waiting call or held call)
1X – Terminate a specific call X
2 – Place all active calls on hold and accept the other call (waiting call or held call) as
the active call
2X – Place all active calls except call X on hold
3 – Add the held call to the active calls
4 – Connect two calls and cut off the connection between users and them simultaneously
Examples
AT+CHLD=?
+CHLD: (0,1,1x,2,2x,3,4)
OK
SIMCOM CONFIDENTIAL FILE

SimCom SIM7600 Series Specifications

General

Brand	SimCom
Model	SIM7600 Series
Category	Control Unit
Language	English