Datasheet

6. Function Description 35
6.4.4 Sleep Modes
Attention! Sleep modes only function correctly when the PIN of the SIM card has been
authenticated. (Either by entering the PIN with AT+CPIN or by deactivating
the PIN query.)
6.4.4.1 Sleep Mode Off (Normal Mode)
AT+CFUN=1
This is normal operation.
6.4.4.2 NON Cyclic Sleep Mode
AT+CFUN=0
In this sleep mode the serial interface is deactivated.
Each possible “wake-up event” in this mode (besides AT commands) causes the INSYS
GSM small to switch to normal mode.
6.4.4.3 Cyclic Sleep Mode
AT+CFUN=5, AT+CFUN=6, AT+CFUN=7, AT+CFUN=8
Common to all these sleep modes is that they poll the serial interface periodically to use
AT commands without leaving the sleep mode.
In each cyclic sleep mode the application as well as the INSYS GSM small should use
hardware handshake, because the INSYS GSM small indicates by activating or
deactivating the CTS control line that it is currently receiving AT commands (polling).
The polling cycle of the serial interface is linked to the so-called paging queries of the
INSYS GSM small to the GSM base station and lasts between 0.47 and 2.12 seconds.
For each polling the CTS line is active for 4.7 ms, then further 4.6 ms activity of the serial
interface of the INSYS GSM small follow (ready to receive). When within those 9.2 ms the
start bit of a character is detected on the serial interface, CTS stays active and the
character is received.
After a character was received the serial interface stays active:
- 2 seconds for AT+CFUN=5 or AT+CFUN=7
- 10 minutes for AT+CFUN=6 or AT+CFUN=8
CTS is also activated when the INSYS GSM small sends characters to the application
within the framework of non-synchronized event codes.
In the intervals between the paging queries, CTS is inactive and therefore also the serial
interface.
When AT+CFUN=5 and AT+CFUN=6 is set, the sleep mode is permanently exited after an
SMS or a connect, and the INSYS GSM small runs again in normal mode (AT+CFUN=1).
Version 1.00 / 09.04