Manual

Smart Machine Smart Decision
SIM800 Series_AT Command Manual_V1.09 71 2015-08-03
OK
Parameters
See Write Command
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.
Note These supplementary services are only applicable to tele service 11
(Speech: Telephony).
OK
If error is related to ME functionality:
+CME ERROR: <err>
Write Command
AT+CHLD=<n>
Parameters
<n> 0 Releases all held calls or sets User Determined User Busy
(UDUB) for a waiting call
1 Releases all active calls (if any exist) and accepts the other
(held or waiting) call.
1x Releases a specific call x
2 Place all active calls on hold (if any) and accept the other
(held or waiting) call.
2x Places all active calls on hold except call X with which
communication shall be supported.
3 Adds a held call to the conversation.
4 Connects the two calls and disconnects the subscriber from
both calls(ECT)
Parameter Saving
Mode
NO_SAVE
Max Response
Time
20s
Reference Note
3.2.15 AT+CIMI Request International Mobile Subscriber Identity
AT+CIMI Request International Mobile Subscriber Identity
Test Command
AT+CIMI=?
Response
OK
Execution
Command
AT+CIMI
Response
TA returns <IMSI>for identifying the individual SIM which is attached to
ME.
<IMSI>