> 3.10.6 | RTC Backup Supply

> The Real Time Clock (RTC) is supplied from a separate voltage inside the TC65 Terminal which is also active when the GSM module is in POWER-DOWN mode. An alarm function is provided for activating/deactivating GSM module (activating only to alarm mode).
> You can use the BACKUP pin on the 24pole I/O connector to backup the RTC from an external battery (non-chargeable).

> Table 17: | RTC signal description

> Signal name | Pin | Description
> BACKUP | 11 | External battery
> GND | 12 | Ground

> If no backup battery is connected then a 100uF capacitor supplies the RTC about 6s during power interruptions.