Diamond Flower's MBI-MIO Card and DIO-200X Card 
With these cards, Diamond Flower supply 2 programs, GETCLOCK.COM and SETCLOCK.COM.
GETCLOCK fetches the date/time from the card and uses it to update the system clock in DOS.  A reference to GETCLOCK is placed in the AUTOEXEC.BAT file so that GETCLOCK is run each time the computer is turned on.
SETCLOCK is only used when the card's date/time becomes incorrect (or to set up the card after battery replacement).  To correct it, DOS' date and time commands are used after SETCLOCK is run, ie.
   C:\>setclock
   C:\>date
   C:\>time
GETCLOCK.COM
SETCLOCK.COM
Link to DIO-200X  User's Manual   (includes usage notes for GETCLOCK and SETCLOCK on page 7-1)