The following cores have to do with date and time keeping.
There is a scene in a movie where a failed date/time update is critical. I forget the name of the movie, but it presents one of the issues with date/time cores. Taking snaphots of the current date/time in order to get an accurate reading, and stopping the clock while doing date/time updates.
One of the date/time cores below (DateTime.v) deals with the issue of different date/time systems. Not everybody uses the same time and calendar systems.
Below: Picture of MC146818AP
|ts_timer||system time slice timer more||ts_timer.v|
|spic||simple priority interrupt controller more||spic.v|
|bc6526timer||6526 compatible timer core|
|bc6526tod||6526 compatible time of day clock more||bc6526tod.v|
|DateTime||date / time core more||DateTime.v|
|clk60Hz||generates 50/60Hz clock pulses||clk60Hz.v|