
Microsoft Year 2000 Readiness Disclosure
& Resource Center |
 |
 |
 |
Windows Operating System Interactions
with BIOS and Real Time Clock |
 | 12.
Summary
Achieving Year 2000 readiness in a computing system is a
process which encompasses hardware, software, and data. Most RTC
rollover issues are remedied by the PC's BIOS. Still others are
remedied by the PC's operating system.
The PC
Y2000 Alliance, which includes many leading PC manufacturers and
BIOS suppliers, has just made the hardware portion of that process
simpler. With broad cooperation, the Alliance has defined hardware
compliance, and provided help to users via the new web site. This
web portal provides the information, assessment, and remediation
tools needed to achieve Year 2000 hardware readiness.
Windows« operating systems insulate applications from most,
although not all, Year 2000 rollover issues. The easy-to-follow
steps included in this paper can be used to check the Year 2000
readiness of your PC's RTC/BIOS and operating system. From time to
time, Microsoft makes available free Year 2000 software updates for
operating systems and applications. Microsoft recommends that
customers install the free Year 2000 software updates prior to
conducting Year 2000 rollover tests. When the Windows« NT operating
system is booted, it directly accesses the RTC memory and uses its
time and date values to set the system time and date. Whenever
Windows NT reads dates between 1900 and 1919 in the RTC it adds 100
to the year. In effect, it maps the time period forward to 2000 û
2019. Windows NT does not add 100 to dates between 1920 and 1999.
Logic built into the Windows« 98 operating system will
automatically set the date forward at boot time if the BIOS does not
roll over the RTC to 2000. The system does not automatically
compensate for BIOSes that do not recognize dates after 12/31/1999.
Users of Windows« 95, Windows 3.x, and MS-DOS version 5.x or
later can address most rollover errors by simply resetting the date
in Control Panel or by using the DATE command in MS-DOS.
Some software development programs use a file-based version
control system that affixes a "time stamp" to data files. This time
stamp contains date information obtained from the system clock. If
the BIOS/RTC fails to reset the system clock to January 1, 2000 (and
if the operating system does not automatically correct the date) new
files and new versions will be saved with incorrect time stamps.
This could corrupt data in the history database.
Many manufacturers have developed products to help users deal
with RTC/BIOS issues and the Year 2000. For links to third party
suppliers, select "BIOS" in the Year 2000 Tools
at the Microsoft Year 2000
Readiness Disclosure & Resource Center Web site. Microsoft
has not tested, and makes no warranties concerning, any third-party
products or resources such as those listed above.
Microsoft recommends that customers carefully evaluate their
systems and test their computing environment from end to end to
address overall Year 2000 issues.
For more information
See the Windows
Update Web site for operating system updates.
See the Microsoft Product Support Services Web site for updated
Windows NT Service Packs
For links to third party suppliers, see the Year 2000 Tools
at the Microsoft Year 2000
Readiness Disclosure & Resource Center Web site.
For more information on the Year 2000 readiness of Microsoft
operating systems, Microsoft development tools, and applications,
see the Year 2000
Product Guide.
|