How do they make Verilog code for unknown ICs?
swiftgriggs at gmail.com
Mon Jun 20 15:36:27 CDT 2016
On Mon, 20 Jun 2016, Ian Finder wrote:
> The hardest part of the process is distilling the functional
> specification of the part you are trying to replace. This is the heart
> of the topic.
Hmm, okay so that's pretty much what I expected. They start with what that
particular chip or ROM etc.. _does_ then they re-implement as a process of
discovery. Does that sound accurate?
> There is no one approach, it is more art than science.
That's also what I expected. I guess as I was reading through other
material, I got the impression that it might be more deterministic, but my
gut feeling was right, I think. Nothing is ever *that* easy.
> For going from a functional specification to a synthesizable model, this
> is simply writing HDL. I suggest this book, which covers the basics of
> this process.
Whoa. That's a pricey sucker. I'm probably not going to be able to make
use of Verilog for a little bit yet. I'm still designing all my little
"homework assignment" type projects on paper or using a tool I found in
pkgsrc called "The Eagle Layout Editor." It's got some nice features (at
least for me so far). I'll probably go with the Wirth book since it's a
bit cheaper, but I still appreciate your suggestion.
> If you have no 100-level understanding of digital logic, start here:
I have about a 100-level understanding, now. I took a digital logic class
in college and I still have my book. It's "Fundamentals of Digital Design"
I believe (or something very close to that). It was a while back, though.
I understand boolean logic, changing base for numbering systems, etc..
However, I have a breathtaking lack of experience in applying that stuff
to "real" digital logic. I'm just using online tutorials and guides for
the moment, but the main one I focus on is this one:
So far, it's been great. I'm just finishing up some of the analog stuff on
that same site, and I've greedily skipped ahead a bit to digital. However,
I'm just now getting to TTLs and gates. I have to actually write out
examples or test things physically to really "get it". However, I'm just
plodding along. I have a nice little mess happening on my workbench in the
garage. I'm about to move on past just using simple capacitors, resistors,
and diodes to using some ICs. It's a little intimidating, actually. I
thought I could get to the point I'm at now in about two weeks. It
actually took about five or six weeks (just for an analog refresher). I'm
still a bit shaky on some of that stuff, too. It's hard to test/see
everything. So, some things I just read about, shrug, and keep going.
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