From: Dan Cross <crossd@gmail.com>
To: Paul Winalski <paul.winalski@gmail.com>
Cc: Paul Ruizendaal <pnr@planet.nl>, "tuhs@tuhs.org" <tuhs@tuhs.org>
Subject: [TUHS] Re: CRC calculation in the 1980s
Date: Tue, 19 Sep 2023 11:50:19 -0400 [thread overview]
Message-ID: <CAEoi9W7iObAp0sitA0-uYOD9uJGLAncJ2ukhr+8Er6_POCPxhw@mail.gmail.com> (raw)
In-Reply-To: <CABH=_VQCRfRZjXpLqFeCM2j4CM_xz6yH1d2JR2UHe-sgVdRAiw@mail.gmail.com>
On Tue, Sep 19, 2023 at 11:34 AM Paul Winalski <paul.winalski@gmail.com> wrote:
> For what it's worth, the VAX had a table-driven CRC instruction. It
> wasn't very popular because on most VAX models it was actually slower
> than by-hand coding. It is one of the instructions dropped from the
> microVAX instruction set used on all later VAXen, where it was
> emulated by the operating system.
I thought that was a general polynomial root finder instruction that
used Horner's Method? Obviously it could be used in CRC calculations,
but I remember it being more general. I also remember reading about it
in the VAX architecture manual and thinking, "wow,
that's...something."
- Dan C.
next prev parent reply other threads:[~2023-09-19 15:51 UTC|newest]
Thread overview: 9+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-09-18 23:02 [TUHS] " Paul Ruizendaal
2023-09-18 23:34 ` [TUHS] " Robert Brockway
2023-09-19 0:02 ` segaloco via TUHS
2023-09-19 15:34 ` Paul Winalski
2023-09-19 15:50 ` Dan Cross [this message]
2023-09-19 16:22 ` Paul Winalski
2023-09-19 11:42 Noel Chiappa
2023-09-19 12:54 ` Lars Brinkhoff
2023-09-19 16:00 ` Paul Ruizendaal
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