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From: Dan Cross <>
To: Will Senn <>
Subject: [TUHS] Re: Bell Labs CSTRs
Date: Sat, 1 Jul 2023 13:28:00 -0400	[thread overview]
Message-ID: <> (raw)
In-Reply-To: <>

On Thu, Jun 29, 2023 at 11:05 AM Will Senn <> wrote:
> Clem's +1 caught my attention, so I looked into the referenced docs. I saw the rather simple (conceptually) m6 processor described in tech note 54. I like its understandable.
> Why is it called m6? Just curious.

I'll take a stab at that; I presume it's due to the naming convention
for macro processors from Bell Labs. Consider m4, which itself was
written as, "an extension of a macro processor called M3 which was
written by D. M. Ritchie for the AP-3 minicomputer; M3 was in turn
based on a macro processor implemented for [1]." (from, "The M4 Macro
Processor" by Brian Kernighan and Dennis Ritchie, as distributed with
4.3BSD; reference [1] is to "Software Tools" by Kernighan and

Anyway, once you've got M3 and M4, you've got a naming convention; I'd
think it a safe bet that there was an M5 that was an internal
experiment, and that M6 was simply the next in line and was
interesting enough to be documented in a tech report.

        - Dan C.

Aside: the AP-3 minicomputer came up on this list a few years ago,
when Dag Spicer of the Computer History Museum was looking for
information about it. Near as folks could figure, it was the computer
portion of a Bendix "stereoplotter" for creating terrain maps and the
like (Adam Sampson figured that part out; others derived Bendix from
part numbers taken from a US Air Force spare parts requisition
document I found).

> On 6/29/23 09:40, Clem Cole wrote:
> +1 👍
> ᐧ
> On Thu, Jun 29, 2023 at 3:37 AM Noel Hunt <> wrote:
>> Many thanks.
>> On Thu, 29 Jun 2023 at 17:14, <> wrote:
>> >
>> > Available at
>> >
>> > Warren and Brantley and anyone else, feel free to retrieve.
>> >
>> > I have two sets - both are in the tarball so there are undoubtedly
>> > duplications.  If someone else can curate them into single canonical
>> > set that'd be helpful, I just don't have the time right now.
>> >
>> > Enjoy,
>> >
>> > Arnold

  reply	other threads:[~2023-07-01 17:28 UTC|newest]

Thread overview: 10+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2023-06-29  7:14 [TUHS] " arnold
2023-06-29  7:36 ` [TUHS] " Noel Hunt
2023-06-29 14:40   ` Clem Cole
2023-06-29 15:04     ` Will Senn
2023-07-01 17:28       ` Dan Cross [this message]
2023-07-01 18:03         ` segaloco via TUHS
2023-07-01 18:42           ` Dan Cross
2023-06-29 15:14     ` Will Senn
2023-08-26 17:02 Nelson H. F. Beebe
2023-08-27  3:13 ` Jonathan Gray

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