Duilio Foschi wrote:
>
> Are there uPs with clock/calendar as an internal feature ?

Yes, for example: NEC uPD 78F0034

-Flash 32 kB + 1 kB SRAM
-8 ch. 10b ADC
-RTC on chip
-SPI, IIC, UART
-selectable clock
-free tools (max. 4 kB)

More at http://www.ic.nec.co.jp/english/products/micro/micro_doc.html

--
Regards
           Petr Krc