This page provides links to a series of product design pages,
showing how the emulator was constructed and providing information
in sufficient detail that, I believe, any of the more criminally
insane programmers among us could build their own emulator.
The following subjects are presented. All material relates to
current versions of the emulator; if you are running the frozen r4
you may note some differences.
— describes the overall design of the emulator, showing
how all the pieces fit together and how data and time flow
through the emulator. If this is your first look at the H8
emulator, this is the best place to start.
— a discussion of time: how we define it, create it, and
distribute it to time consumers;
— a discussion of the performance characteristics of the
emulator, with a presentation of test tools and benchmark
— a poorly named but vital module that glues the 8080A
to the emulator's I/O and interrupt structure;
— covers instruction dispatch, registers and flags,
memory write protection and interfacing to I/O;
— talks about I/O interfacing and 825x emulation;
— discusses keypad and keyboard handling, LED update and
h-17 disk system
— details the operation of the H-17 Disk System in fine
— describes the H-19 Terminal in detail, including all
function key sequences and output escape sequences;
— describes the Serial I/O processes: printing,
Macintosh bidirectional file transfer and modem support;
— describes the implementation and operation of the
PAM/8 cassette tape emulation.
I would be proud to accept and will gratefully acknowledge any
errors, gross omissions or outright lies that you spot on these
pages. I want this material to be accurate.
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