

8085 Microprocessor Reference Card for Programmers - saundby
http://catsonkeyboards.blogspot.com/2011/04/8085-microprocessor-reference-card.html

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kwantam
Ahh, a simpler time. Compare to today's (approximate) equivalent:

 _Intel 64 and IA-32 Architectures Optimization Reference Manual_
<http://www.intel.com/Assets/PDF/manual/248966.pdf>

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luu
Even though I see a graph of how memory accesses have gotten slower relative
to everything else at every conference I attend, it's still striking to see
how much relative cycle times have changed. IN and OUT are now serializing
instructions that have a penalty of hundreds of clocks, not even including
time spent waiting for the I/O itself, as they flush the machine or cause some
scheduled instructions to replay, depending on whether or not your micro-
architecture supports dependent replay. The memory access instructions aren't
quite so bad, since they might hit in the cache, and they don't create a
serializing memory barrier, but they can still be hundreds of cycles.

Correctly predicted branches now have a cost of 1, and almost all branches are
correctly predicted (and they're actually free on the P4, if they're already
in the trace cache). The arithmetic instructions are now single cycle, too,
and multiple copies of them can execute in the same cycle (and they're only
half a cycle on early P4 micro-architectures).

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msarnoff
If you want to put this info to use, check out Stefan Tramm's JavaScript 8080
and CP/M emulator: <http://www.tramm.li/i8080>

Aside: The 8085, despite its similar part number, is not actually an x86 chip.
It used the 8-bit 8080 architecture: the Z80 was an enhanced 8080 that
achieved much greater popularity than its ancestor.

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pasbesoin
Well, that was an enjoyable rabbit hole! (Including traveling deep into the
linked pages.) :-)

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snorkel
I'll file this under "Things I Needed 20 Years Ago" but thanks.

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mdaniel
I don't get the impression this was posted for its "hotness," but rather for
its nostalgia. Well, partially nostalgia and some HN readers may have never
seen an 8086 before in their lives; so in that way, it's a history lesson,
too.

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wglb
8085 is an 8-bit machine; the 8086 is a 16-bit machine.

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wglb
I wore a small number of these out while writing a compiler for the 8085.

