Check Time: get the
time from the RTC and display it in the program.
Set PC to ClockCard:
sets the computer clock to RTC clock.
Set ClockCard to PC:
sets the RTC to the computer clock.
ClockCard & PC time
diff: shows the difference (in ms) between the computer and RTC
Set Backup to ClockCard:
set the backup clock on the RTC to the primary clock on RTC.
Set backup to PC:
set the backup clock on the RTC to the PC.
Set ClockCard to Backup:
set the main clock on the RTC to the backup clock.