NCR RealPOS 80c, Руководство пользователя

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Chapter 6: Memory Dump 6-7
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No control header information is added to the diskette dump files.
Human error can cause memory dump images to be rebuilt
incorrectly. An example would be mixing files from different
memory dumps.
•
No video or keyboard interaction during the memory dump
process is provided. All information is provided to the user by way
of speaker tunes and beeps.
•
If a protect mode NMI hander is not set up to direct NMIs to the
real mode vector captured by the Memory Dump ROM, the system
experiences the default protect mode NMI handling defined by the
operating system and/or compilers used. Often this is a fatal
system error.
•
When the dump switch is pressed the signal SERR# is introduced
onto the BUS producing a NMI. If the Memory Dump ROM’s NMI
handler is not invoked at this time, further activation of the
memory dump switch will not produce a NMI as no software has
run to re-enable the SERR# signal to produce a NMI. This would
only occur in real mode if third party software captured the NMI
vector and did not forward it to its previous handler. Under protect
mode this can occur if the dump button’s NMI is handled by the
default protect mode NMI handler.
•
The register contents stored within the pseudo CMOS storage in
the resulting dump are those seen at entry to the Memory Dump
ROM’s NMI handler and do not specifically match those that
would be most useful - those of the application interrupted.
•
Intel 386 or higher processor, required as the Memory Dump ROM,
is compiled with the .386 option in order to fully save the CPU
state.
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Diskette drive must support change line.
•
512 bytes is the only supported sector size. This is the sector size
MS-DOS is hard coded throughout to support.