The ARMmite, ARMweb, DINkit and SuperPRO have a provision to add a battery to keep these time functions running when power is removed. That battery (ML2020) has to be installed by the user or can be special ordered for larger volume customers.
The BASICchip does not have RTC hardware. The PROplus board does not have the RTC crystal installed.
#include <RTC.bas> ' source in /Program Files/Coridium/BASIClib
FUNCTION DAY(value) ' when called with 0, the current day is returned, otherwise set the current day
Function setting or returning the day of the month.
When called with a non-zero value, the DAY is changed.
Range 1 to 28, 29, 30, or 31
(depending on the month and whether it is a leap year).