The set command sends a new message or delivery status ACK. A client receiving unsolicited notifications for new messages and delivery status is mandated to acknowledge those. This command can be used only when the modem is activated.
If the User Equipment (UE) does not get an acknowledgement within the required time (network timeout), it should respond as specified in 3GPP TS 24.011, and UE/Terminal Adapter (TA) shall automatically disable routing to the Terminal Equipment (TE) by setting both <mt> and <ds> values of +CNMI to zero, that is, the SMS client gets unregistered. In that case, the Mobile Equipment (ME) informs the TE client with a CMS ERROR: 524 notification.
Syntax:
+CNMA[=<n>[,<length>[<CR>PDU is given<ctrl-Z/ESC>]]]
The set command parameters and their defined values are the following:
The following command example confirms the reception of a message, timestamp 06/11/2071 13:26:31:
AT+CNMA=1,9<CR>010017116031621300<ctrl-z>
OK