Year 2000 Compliance
Statement
Definition of Year 2000
Compliance Our definition of year
2000 compliance is that a PC correctly stores & manipulates dates
from the Twentieth to the Twenty-first century, including leap years,
providing the date is properly supplied to the PC by any operating
system, application or peripheral device interacting with it.
Role of Real Time Clock, CMOS and BIOS
The system date and time in our motherboards
is maintained in a Real Time Clock which is given power backup from a
battery.The year, month, day, hour and second are stored as 2 digit
values in byte wide registers that can be read or written by software.
This RTC storage format allows years to be represented by a value
ranging from "00" to "99".
The component that contains the RTC device also
contains battery backed CMOS memory used to store system configuration
information. The system BIOS uses a byte of this CMOS memory to store
the century portion of the year. When this figure is separated from
the RTC it must be set and maintained by the BIOS.
The BIOS provides a set
of services that can be used by operating systems and application
software to set or retrieve the system time and date.The BIOS is
capable of dealing with both century and year values, and therefore
allows the operating system and application software to manipulate the
year as a 4 digit value. |