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UMTS/HSPA Module Series
WCDMA UGxx AT Commands Manual
WCDMA_UGxx_AT_Commands_Manual Confidential / Released 173 / 247
+CCWA: "02154450293",129,1,,0
//Indication of a call that has been waiting
11.3. AT+CHLD Call Related Supplementary Services
The AT+CHLD command allows the control of the following call related services:
A call can be temporarily disconnected from the MT but the connection is retained by the network;
Multiparty conversation (conference calls);
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 and added to a conversation, and transferred similarly as
defined in 3GPP TS 22.030.
This is based on the GSM/UMTS supplementary services HOLD (Call Hold; refer to 3GPP TS 22.083
clause 2), MPTY (Multi Party; refer to 3GPP TS 22.084) and ECT (Explicit Call Transfer; refer to 3GPP TS
22.091). The interaction of this command with other commands based on other GSM/UMTS
supplementary services is described in the GSM/UMTS standards. Call Hold, Multi Party and Explicit Call
Transfer are only applicable to teleservice 11.
AT+CHLD Call Related Supplementary Services
Test Command
AT+CHLD=?
Response
+CHLD:
(list of supported
<n>
s)
OK
Write Command
AT+CHLD[=<n>]
Response
TA controls the supplementary services call hold, multiparty
and explicit call transfer. Calls can be put on hold, recovered,
released, added to conversation and transferred.
OK
If error is related to ME functionality:
+CME ERROR: <err>
Maximum Response Time
300ms
Reference
3GPP TS 27.007
Quectel
Confidential