This commit is contained in:
Neil Webber 2023-11-01 09:19:36 -05:00
parent fbc66608dc
commit f2c1c20857

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NOTES
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Miscellaneous notes about the emulation
******************
ABOUT PDPASMHELPER
******************
This started as a way to make it easier for me to write simple
assembly-language test programs. I really wanted to avoid reimplementing
a full-blown assembler, so it was mostly about opcodes and addr modes.
Then I got tired of hand-calculating labels for simple jumps/loops.
So the InstructionBlock was born, and the label support, including
forward references.
The whole implementation of that is, in my opinion, a ridiculous hack and
it has a lot of rough-edges and surprising semantics.
It is what it is; it works good enough for the pdptests and the
occasional hack/test program. The whole thing should probably just be
chucked out the window as I am not super-interested in turning
the "assembly helper" into a full-featured bug-free assembler...
It really should just be replaced with a real assembler/toolchain.
****************************
RUNNING OTHER LEGACY SYSTEMS
****************************
I have tried to boot unixv6, but it requires an RK emulation. Emulating
those drives should not be difficult but I just haven't gotten to it.