User's Manual
UL865-N3G Hardware User Guide
1VV0301177 Rev 2– 2015-04-20
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Reserved. Page 53 of 70
Mod. 0805 2011-07 Rev.2
13.5. SIMIN detect function
All the GPIO pins can be used as SIM DETECT input. The AT Command used to enable the
function is:
AT#SIMINCFG
Use the AT command AT#SIMDET=2 to enable the SIMIN detection
Use the AT command AT&W0 and AT&P0 to store the SIMIN detection in the common
profile.
For full details see AT Commands Reference Guide, 80000ST10025a.
NOTE:
Don’t use the SIM IN function on the same pin where the GPIO function is enabled and vice
versa!
13.6. RTC Bypass out
The VRTC pin brings out the Real Time Clock supply, which is separate from the rest of the
digital part, allowing having only RTC going on when all the other parts of the device are off.
To this power output a backup capacitor can be added in order to increase the RTC autonomy
during power off of the battery. NO Devices must be powered from this pin.
In order to keep the RTC active when VBATT is not supplied it is possible to back up the
RTC section connecting a backup circuit to the related VRTC signal (pad 30 on module’s
Pinout).
For additional details on the Backup solutions please refer to the related application note
(RTC Backup Application Note)
13.7. SIM Holder Implementation
Please refer to the related User Guide (SIM Holder Design Guides, 80000NT10001a).