Ericsson T39 At Command Reference page 88

4.17.2 Unsolicited result codes
+CKEV
Description:
Unsolicited result code:+CKEV: <keys>,<press>
Parameters:
<keys>:
<press>:
+CIEV
Description:
Unsolicited result code:+CKEV: <ind>,<value>
Parameters:
<ind>:
<value>:
Keypad Event
Keypad event reporting is enabled by the
press/release.
See AT+CKPD.
<press>
0
1
Indicator Event
Indicates changes in indicator levels. Enabled with AT+CMER.
Indicates the indicator order number (as specified for AT+CIND)
<ind>
1
2
3
4
5
6
7
8
9
10
11
Integer; new value of the specific indicator.
AT+CMER
Description
Key released
Key pressed
Description
Battery charge level indicator
Signal quality indicator
Battery warning indicator
Charger connected indicator
Service availability indicator
Sounder activity indicator
Message received indicator
Call-in-progress indicator
Transmit activated by voice activity indicator
Roaming indicator
Short message memory storage indicator in the SMS
AT Commands Phone Terminal Terminated
command and indicates key
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