Questions tagged [rtc]
The rtc tag has no usage guidance.
2
questions
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votes
3answers
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Why does DOS ask for the current date and time upon booting?
In most versions of DOS, when they are started from a medium that lacks an AUTOEXEC.BAT file, the very first thing COMMAND.COM does is ask the user to confirm the current date and time:
Starting PC ...
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vote
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Performing 16-bit port I/O on the RTC
Why can’t the RTC (0x70, 0x71) read and write 16 bits at a time? For example:
mov ax, 0xa8f
out 0x70, ax
I have found in a 286 BIOS that did this (BIOS ID string: S286-6181-...
