My ADM-3A Dumb Terminal has an aggravating tendency to key bounce. It's
not the highest quality keyboard I've ever encountered, and the
circuitry appears to have (at best) 2-key rollover.
Currently I'm using it to talk to my PiDP-8/I at either 110 baud (to
simulate the Teletype experience) or 1200 baud.
Has someone already made improvements to the key scanning circuitry, or
do we just live with it ("that's what they all do")?
I haven't used one regularly since 1981 (senior year in college) 😉 but
don't remember it being quite this annoying.
thanks.
It's been a while since my initial posting about this project but it is time
for an update.
This has been mostly a spare time project, and you know how life tends gets in
the way sometimes...
The work itself has been a bit of a "maze of twisty little passages, all
alike" with many potholes and obstacles, but progress has been made.
The video below tells the tale:
https://youtu.be/KwaNschJg6w
Synopsis:
A real PDP-11/70 boots RSTS/E V10.1 through it's unmodified RH70 controller
with the data coming from the Massbus emulator.
Operation is rock solid and so far have not been able to break it. It also
passes the ERHAE1 XXDP diagnostic without errors.
We now have a viable option for modern storage for Massbus systems.
Still to do is performance optimizations, hardening against some edge cases,
and a large amount of code cleanup.
I only have a PDP-11/70 to test with, but it *should* work with any Massbus
system. Adherence to the DEC Massbus Specification was strict and every
attempt made to make it behave as a proper Massbus device rather than just
coding things to make the RH70 happy.
I am kicking around the idea of putting together a blog chronicling the
various trials, tribulations and milestones encountered along the way if
anyone is interested in reading the gory details....
Cheers!
Jim
Hi all,
I have a complete set of RT11 V5 manuals that I am getting rid of.
Never used!
I cannot ship, so only for pickup in Toronto.
cheers
Nigel
--
Nigel Johnson, MSc., MIEEE, VE3ID/G4AJQ/VA3MCU
Amateur Radio, the origin of the open-source concept!
Oh what a mangled head received when first we fractals do perceive
I just finished scanning the DEC documentation for the KH11-A "NPR
Expansion" option for the PDP11/20 and the PDP11/05 machines. (I just
bought this drawing set on eBay...)
As far as I can tell, this is the only documentation for this CPU
modification that's online - aside of course for my own reverse-engineering
drawings from earlier this year.
You can find the drawings here.
<https://deramp.com/downloads/mfe_archive/011-Digital%20Equipment%20Corporat…>
I believe this is a complete documentation set. The page order is a bit
funky, but it is in the original page order - I had to remove the (very
rusty) original staples to be able to scan it all.
Note that in addition to the complete print set, I've also included
additional drawings for the M724-YA, for later revisions of that board.
Martin
> Date: Thu, 1 Oct 2026 19:49:36 -0400
> From: Paul Koning<paulkoning(a)comcast.net>
> Subject: [cctalk] APL-11 sources
> To:"cctalk(a)classiccmp.org" <cctalk(a)classiccmp.org>
> Message-ID:<7743C081-B2D1-4788-9E52-AB946F9A1D30(a)comcast.net>
> Content-Type: text/plain; charset=us-ascii
>
> I was just wandering through some old disk images and spotted something I missed for years: a directory holding what looks like a set of source files and build scripts for APL-11.
>
> I have no idea where this came from or why I have it; while I have used APL I have not used it on a PDP-11, nor ever installed it.
>
> Is this something others already have that is a known to be good version, or should I go dig through this and verify it, then archive it properly?
>
> paul
>
>
> ------------------------------
>
> Message: 4
> Date: Thu, 1 Oct 2026 20:08:37 -0400
> From: Bill Gunshannon<bill.gunshannon(a)hotmail.com>
> Subject: [cctalk] Re: APL-11 sources
> To:cctalk@classiccmp.org
> Message-ID:<SJ0PR11MB5815FB606E1B75ACD17CB39DED892(a)SJ0PR11MB5815.nam
> prd11.prod.outlook.com>
> Content-Type: text/plain; charset=UTF-8; format=flowed
>
>
>
> On 10/1/2026 7:49 PM, Paul Koning via cctalk wrote:
>> I was just wandering through some old disk images and spotted something I missed for years: a directory holding what looks like a set of source files and build scripts for APL-11.
>>
>> I have no idea where this came from or why I have it; while I have used APL I have not used it on a PDP-11, nor ever installed it.
>>
>> Is this something others already have that is a known to be good version, or should I go dig through this and verify it, then archive it properly?
>>
> I would imagine it is the one distributed by DECUS. I have a copy here
> somewhere but I, too, never got around to getting it working. And, yes,
> I know and have used APL on a number of different machines.
>
> bill
>
>
> ------------------------------
>
> Message: 5
> Date: Thu, 1 Oct 2026 20:23:19 -0400
> From: Paul Koning<paulkoning(a)comcast.net>
> Subject: [cctalk] Re: APL-11 sources
> To:"cctalk(a)classiccmp.org" <cctalk(a)classiccmp.org>
> Cc: Bill Gunshannon<bill.gunshannon(a)hotmail.com>
> Message-ID:<667546B6-EFFE-4C1F-B031-33E0F5CFABEC(a)comcast.net>
> Content-Type: text/plain; charset=utf-8
>
>
>
>> On Oct 1, 2026, at 8:08 PM, Bill Gunshannon via cctalk<cctalk(a)classiccmp.org> wrote:
>>
>>
>>
>> On 10/1/2026 7:49 PM, Paul Koning via cctalk wrote:
>>> I was just wandering through some old disk images and spotted something I missed for years: a directory holding what looks like a set of source files and build scripts for APL-11.
>>> I have no idea where this came from or why I have it; while I have used APL I have not used it on a PDP-11, nor ever installed it.
>>> Is this something others already have that is a known to be good version, or should I go dig through this and verify it, then archive it properly?
>> I would imagine it is the one distributed by DECUS. I have a copy here
>> somewhere but I, too, never got around to getting it working. And, yes,
>> I know and have used APL on a number of different machines.
>>
> Hard to say. The source files don't have copyright headers on them at all, but there is an "apl11s.doc" file with a DEC copyright; it seems to be a "support" manual that discusses the internals.
>
> paul
>
> Mark Matlock and I did some work to resurrect the APL-11 that was
> donated to DECUS, for use on later versions of RSX11M+. See details at
> https://rsx11.blogspot.com/2021/02/decus-apl-11-fixes-for-id-space-and.html
> Johnny Billquist did more work on it later, and distributes it by
> his RPM facility for RSX. -- Lee K. Gleason N5ZMR Control-G
> Consultants. lee.gleason(a)gmail.com
Paul, Bill,
Regarding APL-11 and its source code. This was the focus of a software archeology effort in 2021. I had bought the APL-11 package from DECUS on 9-track tape when DEC donated it to DECUS when they decided to no longer sell it. Then could be ordered from the DECUS Library (Order No. 11-SP-25).
Then on the RSX SIG tape RSX85A:[370,360], Bob Awde from General Mills provided a few modified .MAC, .ODL, and .CMD files that converted APL-11 to a I/D space task with FCS Supervisor mode. This gives you a workspace of just over 52,000 bytes on RSX11M+ with a I/D space CPU.
Unfortunately, there were changes made to how TKB overlays task images and these patches and in fact the original source e code could no longer be compiled with RSX TKB. The task images from the original DECUS source ran but one could not rebuild the task from the Macro-11 sources. I struggled with this for a number of years until I got a couple (much smarter than I) friends to get interested in fixing. It.
First, Lee Gleason, figured out what was happening with TKB and the overlays and managed to make some hacks that created a I/D space version of APL-11. He described that work on his RSX blog: https://rsx11.blogspot.com/2021/02/
Then Johnny Billquist saw the blog and decided to work on the distribution. He fixed the .ODL and .CMD to work properly with the new TKB overlay mechanisms, and while he was at it, fixed several bugs in the original APL-11 that affected a number of things. He also modified it to fix a Y2K problem and to handle named directories.
Today if you use Johnny’s RPM package manager APL-11 can be downloaded and the latest version is V2.2.2 Also, there is a VT220 downloadable APL font on that RSX85A Sig tape in [370,361] and a task to compose new fonts.
I also had an APL-11 user’s manual that I scanned and made available at: http://www.rsx11m.com/APL-11-Ref-Man.pdf
The release notes are at http://www.rsx11m.com/APL11ins.pdf
The APL-11 quick reference card is at http://www.rsx11m.com/APL_Reference_Card.pdf
You can also get the APL-11 manuals from Johnny’s virtual PDP-11/74 MIM at http://mim.softjar.se/manuals/LAYERED/
The latest version of the modified sources could be obtained from Johnny as well.
The quick reference card is especially helpful to learn the two letter replacements for APL characters. For example, the square “quad” is .QD so to see the available workspace .QDWA works with standard ascii terminals. Matrix divide (Quad, back-space Divide symbol) is .DQ so .DQM inverts matrix M.
Best,
Mark Matlock
> From: Paul Koning <paulkoning(a)comcast.net>
> Subject: [cctalk] APL-11 sources
> Date: October 1, 2026 at 6:49:36 PM CDT
> To: "cctalk(a)classiccmp.org" <cctalk(a)classiccmp.org>
> Reply-To: "General Discussion: On-Topic and Off-Topic Posts" <cctalk(a)classiccmp.org>
>
>
> I was just wandering through some old disk images and spotted something I missed for years: a directory holding what looks like a set of source files and build scripts for APL-11.
>
> I have no idea where this came from or why I have it; while I have used APL I have not used it on a PDP-11, nor ever installed it.
>
> Is this something others already have that is a known to be good version, or should I go dig through this and verify it, then archive it properly?
>
> paul
>
>
>
>
> From: Bill Gunshannon <bill.gunshannon(a)hotmail.com>
> Subject: [cctalk] Re: APL-11 sources
> Date: October 1, 2026 at 7:08:37 PM CDT
> To: cctalk(a)classiccmp.org
> Reply-To: "General Discussion: On-Topic and Off-Topic Posts" <cctalk(a)classiccmp.org>
>
>
>
>
> On 10/1/2026 7:49 PM, Paul Koning via cctalk wrote:
>> I was just wandering through some old disk images and spotted something I missed for years: a directory holding what looks like a set of source files and build scripts for APL-11.
>> I have no idea where this came from or why I have it; while I have used APL I have not used it on a PDP-11, nor ever installed it.
>> Is this something others already have that is a known to be good version, or should I go dig through this and verify it, then archive it properly?
>
> I would imagine it is the one distributed by DECUS. I have a copy here
> somewhere but I, too, never got around to getting it working. And, yes,
> I know and have used APL on a number of different machines.
>
> bill
>
>
>
>
> From: Paul Koning <paulkoning(a)comcast.net>
> Subject: [cctalk] Re: APL-11 sources
> Date: October 1, 2026 at 7:23:19 PM CDT
> To: "cctalk(a)classiccmp.org" <cctalk(a)classiccmp.org>
> Cc: Bill Gunshannon <bill.gunshannon(a)hotmail.com>
> Reply-To: "General Discussion: On-Topic and Off-Topic Posts" <cctalk(a)classiccmp.org>
>
>
>
>
>> On Oct 1, 2026, at 8:08 PM, Bill Gunshannon via cctalk <cctalk(a)classiccmp.org> wrote:
>>
>>
>>
>> On 10/1/2026 7:49 PM, Paul Koning via cctalk wrote:
>>> I was just wandering through some old disk images and spotted something I missed for years: a directory holding what looks like a set of source files and build scripts for APL-11.
>>> I have no idea where this came from or why I have it; while I have used APL I have not used it on a PDP-11, nor ever installed it.
>>> Is this something others already have that is a known to be good version, or should I go dig through this and verify it, then archive it properly?
>>
>> I would imagine it is the one distributed by DECUS. I have a copy here
>> somewhere but I, too, never got around to getting it working. And, yes,
>> I know and have used APL on a number of different machines.
>>
>
> Hard to say. The source files don't have copyright headers on them at all, but there is an "apl11s.doc" file with a DEC copyright; it seems to be a "support" manual that discusses the internals.
>
> paul
All,
If you haven't worked in the television/broadcast business, you probably won't remember Basys. It was a newsroom computer system (NRCS) written by Basys Inc. in the late 70s/early 80s, sold to ITN in London who maintained it for some years and then sold it to DEC, who then sold it to Avid.
I'm beginning to get some interest from several people in building a Basys installation on emulated hardware. From what I know, it may have run on VAX, SCO UNIX and IRIX, as well as Linux when Avid bought it. But for my purposes, I'm looking to build a system which supports serial terminals, possibly via a device called a communications control unit (CCU).
Having searched all the normal places, I've been unable to find any installation media, no matter how old. Avid's website has some older versions of iNEWS that run on Linux, but this is far too new and doesn't support serial terminals.
Does anyone have any installation media, or any pointers to people who might be able to help?
Peter
