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Learning PDP-11 in 2021 [message #408098] Mon, 10 May 2021 03:44 Go to next message
faux_dameron is currently offline  faux_dameron
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I've never used one of the big old great computers like a PDP-11.

Let's say I'm nuts or at least a big nerd. If I wanted to learn how to
use one today without spending exorbitant amounts of money buying
hardware and a ton of old manuals, how could I go about doing that?

What emulator would you use and what guide would you use to get going?

__
JE
Re: Learning PDP-11 in 2021 [message #408099 is a reply to message #408098] Mon, 10 May 2021 03:53 Go to previous messageGo to next message
Anonymous
Karma:
Originally posted by: Bob Eager

On Mon, 10 May 2021 07:44:19 +0000, Jason Evans wrote:

> I've never used one of the big old great computers like a PDP-11.
>
> Let's say I'm nuts or at least a big nerd. If I wanted to learn how to
> use one today without spending exorbitant amounts of money buying
> hardware and a ton of old manuals, how could I go about doing that?
>
> What emulator would you use and what guide would you use to get going?

SIMH, I would say. Wtitten by a DEC guy who really knows his stuff. You
can select the model to emulate, etc.

A choice of operating systems (and I'll be adding another soon). Plenty
of documentation for it all online, mainly at bitsavers.

There may be flashy ones with GUI panels, but I've been using SIMH for
years and it is *very* solid.



--
Using UNIX since v6 (1975)...

Use the BIG mirror service in the UK:
http://www.mirrorservice.org
Re: Learning PDP-11 in 2021 [message #408100 is a reply to message #408099] Mon, 10 May 2021 04:59 Go to previous messageGo to next message
Anonymous
Karma:
Originally posted by: Schmitty

Bob Eager schrieb am 10.05.2021 um 09:53:
> On Mon, 10 May 2021 07:44:19 +0000, Jason Evans wrote:
>
>> I've never used one of the big old great computers like a PDP-11.
>>
>> Let's say I'm nuts or at least a big nerd. If I wanted to learn how to
>> use one today without spending exorbitant amounts of money buying
>> hardware and a ton of old manuals, how could I go about doing that?
>>
>> What emulator would you use and what guide would you use to get going?
>
> SIMH, I would say. Wtitten by a DEC guy who really knows his stuff. You
> can select the model to emulate, etc.
>
> A choice of operating systems (and I'll be adding another soon). Plenty
> of documentation for it all online, mainly at bitsavers.
>
> There may be flashy ones with GUI panels, but I've been using SIMH for
> years and it is *very* solid.
>
>
>

You could even run ancient Unix on it, see
http://wandel.ca/homepage/unixdemo.html
Re: Learning PDP-11 in 2021 [message #408106 is a reply to message #408100] Mon, 10 May 2021 07:07 Go to previous messageGo to next message
Anonymous
Karma:
Originally posted by: Bob Eager

On Mon, 10 May 2021 10:59:39 +0200, Schmitty wrote:

> Bob Eager schrieb am 10.05.2021 um 09:53:
>> On Mon, 10 May 2021 07:44:19 +0000, Jason Evans wrote:
>>
>>> I've never used one of the big old great computers like a PDP-11.
>>>
>>> Let's say I'm nuts or at least a big nerd. If I wanted to learn how to
>>> use one today without spending exorbitant amounts of money buying
>>> hardware and a ton of old manuals, how could I go about doing that?
>>>
>>> What emulator would you use and what guide would you use to get going?
>>
>> SIMH, I would say. Wtitten by a DEC guy who really knows his stuff. You
>> can select the model to emulate, etc.
>>
>> A choice of operating systems (and I'll be adding another soon). Plenty
>> of documentation for it all online, mainly at bitsavers.
>>
>> There may be flashy ones with GUI panels, but I've been using SIMH for
>> years and it is *very* solid.
>>
>>
>>
>>
> You could even run ancient Unix on it, see
> http://wandel.ca/homepage/unixdemo.html

Oh, I know, Lots of versions up to Seventh Edition. Takes me back to when
I first used Sixth Edition in 1975.

http://simh.trailing-edge.com/software.html

I did the (rare) Mini-UNIX stuff, and the Quasijarus stuff for the VAX.
Just the pages and instructions, not the software!



--
Using UNIX since v6 (1975)...

Use the BIG mirror service in the UK:
http://www.mirrorservice.org
Re: Learning PDP-11 in 2021 [message #408110 is a reply to message #408098] Mon, 10 May 2021 14:26 Go to previous messageGo to next message
Anonymous
Karma:
Originally posted by: David Bridgham

Besides SimH for the emulator, if you want a bit of the look and feel of
the old 11's there's also the PiDP-11.

https://obsolescence.wixsite.com/obsolescence/pidp-11

You then need to add a big fan to get the whooshing sound. Maybe you
should just skip that part.

Dave
Re: Learning PDP-11 in 2021 [message #408111 is a reply to message #408098] Mon, 10 May 2021 14:33 Go to previous messageGo to next message
usenet is currently offline  usenet
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On Mon, 10 May 2021 07:44:19 -0000 (UTC), Jason Evans <jsevans@mailfence.com>
wrote:
> I've never used one of the big old great computers like a PDP-11.

One of the reasons why the PDP-11 was a great computer was because it wasn't
big. You didn't need a raised-floor computer room with a heavy-duty HVAC
system. Ordinary office air-conditioning was usually sufficient. Was 3-phase
power required for the PDP-11 or its peripherals? If not, that would be another
plus for the smaller models.
Re: Learning PDP-11 in 2021 [message #408114 is a reply to message #408111] Mon, 10 May 2021 15:57 Go to previous messageGo to next message
Anonymous
Karma:
Originally posted by: Andy Walker

On 10/05/2021 19:33, Questor wrote:
> One of the reasons why the PDP-11 was a great computer was because it wasn't
> big. You didn't need a raised-floor computer room [...].

Indeed. We carved our computer room out of a basement that
previously contained rather extravagant Ladies and Gents facilities.
The puddles on the floor had been put down to the Gents being less
than gentlemanly, so a raised floor was deemed unnecessary. However,
next time it rained, more puddles. We rang the Works Dept, and
said that unless something could be done in the next hour or so,
some very expensive* computers were in danger. A pump was rapidly
deployed and the danger averted. But it turned out that the [award-
winning] building, by a Famous Architect, had been built over an
un-noticed stream, which flooded every time it rained. Red faces in
the FA's offices.

Yes, the PDP-11 was a great computer. For the first time we
were freed from the tyranny of computers the size of rooms or even
buildings and needing dedicated operators and engineers.

_____
* Expensive by the standards of maths depts, not by the
standards of computing centres.

--
Andy Walker, Nottingham.
Andy's music pages: www.cuboid.me.uk/andy/Music
Composer of the day: www.cuboid.me.uk/andy/Music/Composers/Daquin
Re: Learning PDP-11 in 2021 [message #408115 is a reply to message #408114] Mon, 10 May 2021 16:52 Go to previous messageGo to next message
Anne &amp; Lynn Wheel is currently offline  Anne &amp; Lynn Wheel
Messages: 3156
Registered: January 2012
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Senior Member
Andy Walker <anw@cuboid.co.uk> writes:
> Indeed. We carved our computer room out of a basement that
> previously contained rather extravagant Ladies and Gents facilities.
> The puddles on the floor had been put down to the Gents being less
> than gentlemanly, so a raised floor was deemed unnecessary. However,
> next time it rained, more puddles. We rang the Works Dept, and
> said that unless something could be done in the next hour or so,
> some very expensive* computers were in danger. A pump was rapidly
> deployed and the danger averted. But it turned out that the [award-
> winning] building, by a Famous Architect, had been built over an
> un-noticed stream, which flooded every time it rained. Red faces in
> the FA's offices.


drift computer room flooding

new STL lab opened in the 70s (ref gone 404, but lives on at wayback machine
https://web.archive.org/web/20080512195924/http://www.ajnord ley.com/IBM/Air/SVL/

the above article mentions the interior couryard between the towers and
above "one of the largest computer machine rooms west of the
Mississippi". it also mentions flooding of roads ... but when STL first
open, the computer room was also getting flooded when it rained.

STL also had a different problem opening. IBM had standard naming after
closest Post Office, which was Coyote. However just prior to opening,
the SanFran professional ladies Coyote organization was demonstrating in
Wash DC gov. bldgs. The name was quickly changed to closest cross
street, Santa Teresa (STL) ... more recently changed to Silicon Vally
Lab (SVL).

In the 60s, as undergraduate, I took two semester hr intro to
computers/fortran ... then within a year, I'm hired fulltime responsible
for IBM systems. Then before I graduate, I'm hired fulltime into small
group in the Boeing CFO office to help with the formation of Boeing
Computer Services (consolidate all dataprocessing into independent
business unit to better monetize the investment, including offering
services to non-Boeing entities). I thought Renton datacenter was
possibly largest in the world, 360/65s arriving faster than they could
be installed, boxes constantly staged in the hallways around the machine
room ($200M-$300M in IBM 360s). There was also disaster plan to
replicate renton up at the new 747 plant in Everett (747#3 was flying
skies of Seattle getting FAA flt certification), where Mt. Rainier heats
up and the resulting mud slide takes out the datacenter. The analysis
claimed that being w/o Renton for a week would cost Boeing more than
the cost of replicating the datacenter.

--
virtualization experience starting Jan1968, online at home since Mar1970
Re: Learning PDP-11 in 2021 [message #408117 is a reply to message #408111] Mon, 10 May 2021 17:04 Go to previous messageGo to next message
Anonymous
Karma:
Originally posted by: gareth evans

On 10/05/2021 19:33, Questor wrote:
> On Mon, 10 May 2021 07:44:19 -0000 (UTC), Jason Evans <jsevans@mailfence.com>
> wrote:
>> I've never used one of the big old great computers like a PDP-11.
>
> One of the reasons why the PDP-11 was a great computer was because it wasn't
> big. You didn't need a raised-floor computer room with a heavy-duty HVAC
> system. Ordinary office air-conditioning was usually sufficient. Was 3-phase
> power required for the PDP-11 or its peripherals? If not, that would be another
> plus for the smaller models.
>

.... and the original 28 foot long unibus getting trodden into the floor
and still functioning!
Re: Learning PDP-11 in 2021 [message #408123 is a reply to message #408117] Mon, 10 May 2021 22:40 Go to previous messageGo to next message
Jon Elson is currently offline  Jon Elson
Messages: 646
Registered: April 2013
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Senior Member
gareth evans wrote:

> On 10/05/2021 19:33, Questor wrote:
>> On Mon, 10 May 2021 07:44:19 -0000 (UTC), Jason Evans
>> <jsevans@mailfence.com> wrote:
>>> I've never used one of the big old great computers like a PDP-11.
>>
>> One of the reasons why the PDP-11 was a great computer was because it
>> wasn't
>> big. You didn't need a raised-floor computer room with a heavy-duty HVAC
>> system. Ordinary office air-conditioning was usually sufficient. Was
>> 3-phase
>> power required for the PDP-11 or its peripherals? If not, that would be
>> another plus for the smaller models.
I don't know of any PDP-11 that required 3-phase. Smaller models ran off
120 V AC from a standard wall outlet, maybe our 11/45 used 208 V single
phase. I do remember some issue when it arrived and I tapped it into the
breaker panel until somebody from facilities saw that we had to have a
proper high-power outlet put in.

Some of the bigger disks using Massbus might have needed 3-phase.
I know RP07 did, but that was on our VAX 11/780.

Jon
Re: Learning PDP-11 in 2021 [message #408137 is a reply to message #408098] Tue, 11 May 2021 06:59 Go to previous messageGo to next message
Anonymous
Karma:
Originally posted by: Marco Scholz

On 2021-05-10, Jason Evans <jsevans@mailfence.com> wrote:
> I've never used one of the big old great computers like a PDP-11.
>
> Let's say I'm nuts or at least a big nerd. If I wanted to learn how to
> use one today without spending exorbitant amounts of money buying
> hardware and a ton of old manuals, how could I go about doing that?
[...]

Simh simulates PDP-1, -4, -7, -8, -9, -10 and -11.

However, a PiDP-11 will be the most fun, IMO:

"The PiDP-11 is a modern replica of the PDP-11/70."`
https://obsolescence.wixsite.com/obsolescence/pidp-11

Especially if you like toggles, switches and blinkenlihghts.


--
XMPP tool@disroot.org
DB4CE71C8DEF84257AD0B23E4D5934D90226C7F3 00010011 00010011 ▞
Re: Learning PDP-11 in 2021 [message #408139 is a reply to message #408137] Tue, 11 May 2021 09:49 Go to previous messageGo to next message
Anonymous
Karma:
Originally posted by: Bob Eager

On Tue, 11 May 2021 10:59:05 +0000, Marco Scholz wrote:

> On 2021-05-10, Jason Evans <jsevans@mailfence.com> wrote:
>> I've never used one of the big old great computers like a PDP-11.
>>
>> Let's say I'm nuts or at least a big nerd. If I wanted to learn how to
>> use one today without spending exorbitant amounts of money buying
>> hardware and a ton of old manuals, how could I go about doing that?
> [...]
>
> Simh simulates PDP-1, -4, -7, -8, -9, -10 and -11.
>
> However, a PiDP-11 will be the most fun, IMO:
>
> "The PiDP-11 is a modern replica of the PDP-11/70."`
> https://obsolescence.wixsite.com/obsolescence/pidp-11
>
> Especially if you like toggles, switches and blinkenlihghts.

Agreed, but it's SIMH inside. And SIMH is cheaper (free)!

(I'm still going to get a PiDP-10 to join the -8 and -11).



--
Using UNIX since v6 (1975)...

Use the BIG mirror service in the UK:
http://www.mirrorservice.org
Re: Learning PDP-11 in 2021 [message #408143 is a reply to message #408139] Tue, 11 May 2021 16:27 Go to previous messageGo to next message
Anonymous
Karma:
Originally posted by: Vir Campestris

On 11/05/2021 14:49, Bob Eager wrote:
> (I'm still going to get a PiDP-10 to join the -8 and -11).

I cut my teeth on a PDP-10, the first thing I ever used assembler on.

There's something to do in my retirement!

Andy
Re: Learning PDP-11 in 2021 [message #408145 is a reply to message #408143] Tue, 11 May 2021 18:11 Go to previous messageGo to next message
Anonymous
Karma:
Originally posted by: Bob Eager

On Tue, 11 May 2021 21:27:11 +0100, Vir Campestris wrote:

> On 11/05/2021 14:49, Bob Eager wrote:
>> (I'm still going to get a PiDP-10 to join the -8 and -11).
>
> I cut my teeth on a PDP-10, the first thing I ever used assembler on.
>
> There's something to do in my retirement!

It was the third fort me - my Master's at Essex.



--
Using UNIX since v6 (1975)...

Use the BIG mirror service in the UK:
http://www.mirrorservice.org
Re: Learning PDP-11 in 2021 [message #408149 is a reply to message #408123] Tue, 11 May 2021 22:01 Go to previous messageGo to next message
Anonymous
Karma:
Originally posted by: lawrenabae

Jon Elson <elson@pico-systems.com> writes:

>>> Was 3-phase power required for the PDP-11 or its peripherals? If
>>> not, that would be another plus for the smaller models.

> I don't know of any PDP-11 that required 3-phase. Smaller models ran off
> 120 V AC from a standard wall outlet, maybe our 11/45 used 208 V single
> phase. I do remember some issue when it arrived and I tapped it into the
> breaker panel until somebody from facilities saw that we had to have a
> proper high-power outlet put in.
>
> Some of the bigger disks using Massbus might have needed 3-phase.
> I know RP07 did, but that was on our VAX 11/780.
>
> Jon

This used to be a fairly frequently covered topic 20+ years ago here.
IIRC, some of the largest (11/70-class) machines came with 3-ph power
controllers, but each of the individual loads were strappable for 120V
(for North American customers)

I know my 11/55 with "a couple of RL02 and a couple of RK07" was all
120, but the inlet was 120/240 single phase.


echo "lawrenabae@abaluon.abaom" | sed s/aba/c/g
Re: Learning PDP-11 in 2021 [message #408302 is a reply to message #408110] Tue, 18 May 2021 00:53 Go to previous messageGo to next message
greenaum is currently offline  greenaum
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On Mon, 10 May 2021 14:26:18 -0400, David Bridgham <dab@froghouse.org> sprachen:

> You then need to add a big fan to get the whooshing sound. Maybe you
> should just skip that part.

You can probably get that as a sample. Play it through a Bluetooth speaker.

------------------------------------------------------------ ------------

if love is a drug, then, ideally, it's a healing, healthful drug... it's
kind of like prozac is supposed to work (without the sexual side
effects and long-term damage to the brain and psyche)
Re: Learning PDP-11 in 2021 [message #408680 is a reply to message #408098] Fri, 04 June 2021 09:44 Go to previous messageGo to next message
Anonymous
Karma:
Originally posted by: John Goerzen

On 2021-05-10, Jason Evans <jsevans@mailfence.com> wrote:
> I've never used one of the big old great computers like a PDP-11.

You might appreciate my project at
https://github.com/jgoerzen/vintage-computing . It features support for
both Raspberyy Pi and Docker, offering various emulators and ancient OS
distributions to run under them. The Github readme also contains a lot
of links to emulators and sources of OSs to get you going.

- John

--
jgoerzen@sdf.org
SDF Public Access UNIX System - http://sdf.org
Re: Learning PDP-11 in 2021 [message #408766 is a reply to message #408680] Mon, 07 June 2021 07:07 Go to previous messageGo to next message
Anonymous
Karma:
Originally posted by: jsevans

On Fri, 4 Jun 2021, John Goerzen wrote:

> You might appreciate my project at
> https://github.com/jgoerzen/vintage-computing . It features support for
> both Raspberyy Pi and Docker, offering various emulators and ancient OS
> distributions to run under them. The Github readme also contains a lot
> of links to emulators and sources of OSs to get you going.

Thanks John, I'll check it out. It's also great to see another SDF member!

Best Regards,
jse
Re: Learning PDP-11 in 2021 [message #409282 is a reply to message #408098] Thu, 24 June 2021 15:40 Go to previous messageGo to next message
greenaum is currently offline  greenaum
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On Tue, 11 May 2021 11:29:54 -0400, Andreas Kohlbach <ank@spamfence.net> sprachen:

> Apparently I can emulate a PDP-1 (from 1961?) in MAME, although MAME is
> supposed to only emulate machines with a microprocessor as CPU. So
> machines with i4004 (1971) upwards.

Where did you hear that? I've never heard anything about MAME having some preference for integrated CPUs vs circuit-board ones.
Though that said the "AM" stands for "arcade machine, they let the "M" for "multiple" take precendence over that way back when.
Eventually MAME will be able to emulate any machine that ever existed, including those MAME cabinets that people build. Including
the Morse Code Key, and the bone for hitting other monkeys over the head with.

I never knew, til I'd been into collecting old computers ("retro", -spit!-) for a long time, that Atari, among others, had a whole
line of machines out in the 1970s, using B&W graphics and custom logic circuits, hard-coded to run whatever game. No software,
no CPU.

I can understand doing Pong like that, Pong even lends itself to a TV screen, you draw the bats and everything just by timing as
the electron beam races down the screen. The length of the bats just needs to be a timer, you start it when you begin to draw a
bat, and the time it takes to decay determines whether, when the beam is at the right horizontal column, to draw the bat on this
scanline or not. If the length-timer says "yes", then you do.

You start the length timer according to how far down the screen the bat is to be drawn, affected directly by the player's pot
control. So you reset another timer at the first scanline, then at a rate determined by the control, it waits til the right
scanline to start drawing the bat. That triggers the bat-length timer, which says for how long to draw the bat.

The bat isn't drawn all the time the bat-length timer is on, of course. Only when the horizontal-position of the electron beam
is right where that bat ought to be. When it is, check the bat-length timer, and if it's still on, then we draw one scanline's
worth of bat just there, just a little horizontal slice, like a slice of cheese in an unwieldy Scooby-Doo sandwich.

Anyway... same thing for each bat, and the ball. Similar things for the "goals" if it's a football-type game, I don't think Pong
had that, but the AY-3-8500 based home games, in their millions, did. This is all from supposition and what I've been able to dig
up, I wrote a Pong simulator way back when on PC. It used the "timer" / "scanline" idea, though emulated on a PC, and even had a
couple of the weird effects those units had. Play felt very much like the real thing even if appearances were a bit primitive in
320x200 at 256 colours.

I say "timer", you could use "counter" instead, do it digitally, and use appropriate comparators there. Analogue or digital
doesn't matter much. Atari, in the 2600, were keen to use polynomial counters in everything in it's graphics chip. So that it all
takes the right amount of time to count, I *think*, rather than varying slightly with the varying carries needed for normal
counting. If someone has a better explanation than that, please oblige! Maths not really my thing past the strictly necessary.

Then past Pong, early games used ROMs for little sprites, instead of bats, though not much advance apart from that. I think at
least a couple of them used ACTUAL diode ROM with ACTUAL diodes! On a little PCB, you could see the graphics soldered in there!
Every lit pixel costs the company 2c! Or whatever a diode cost.

Not having software didn't mean you couldn't have RAM or ROM though, then eventually America's favourite washing machine
controller raised it's ugly head! I prefer the Z80 myself. But Atari stuck 6502s in nearly all their early machines. It's a shame
they used B&W graphics, generally black and white, and a mid-grey. Mid-grey would be the default playfield and presumably
be whenever nothing else was sending pixels to the electron beam, it'd default to mid-grey. I suppose B&W CRTs were cheaper,
but the amount of profit arcade games made, surely they could have afforded colour? And make the effort to squeeze a couple more
chips in so we actually got maybe 5 or 6 colours all on the screen at once! Actually yeah I can see why they didn't bother, often
there were very few objects on screen at all, or very few types of object, with multiples of them. Still I reckon colour would
have stood out in the arcade. But maybe any screen at all did, and that was enough.

Prior to that it's the crazy and ingenious world of electro-mechanical amusements. In Blackpool (Brit Seaside resort, the best
one) maybe 15 years ago, on the sea front somebody had set up a bunch of genuine old machines. In exchange for money, he'd give
you a few enormous old pennies to put in their slots to play. You could win those disgusting candy sticks / candy "cigarettes",
but who'd want to? At least make it a lollipop, mate! Did anyone ever like those disgusting things? As kids we only ever bought
them once or twice for a laugh at pretending to smoke.

Anyway, yeah, MAME... the freaky evolutionary effect of open-source, it just thunders ahead like a stampeding mastodon. Linux,
Arduino, MAME, probably the biggest open-source sucesses I think, anyone wanna disagree?

Wow, pardon the long post! Good ol' Usenet! You've got 6 more weeks to think about it, probably, so no worries. It's like the
ooooold days must've been here, very little activity and conversations that stretch over however old long. Nice!

------------------------------------------------------------ ------------

if love is a drug, then, ideally, it's a healing, healthful drug... it's
kind of like prozac is supposed to work (without the sexual side
effects and long-term damage to the brain and psyche)
Re: Learning PDP-11 in 2021 [message #409285 is a reply to message #409282] Thu, 24 June 2021 16:58 Go to previous messageGo to next message
Ahem A Rivet's Shot is currently offline  Ahem A Rivet's Shot
Messages: 4843
Registered: January 2012
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Senior Member
On Thu, 24 Jun 2021 19:40:13 GMT
greenaum@gmail.com wrote:

> I suppose B&W CRTs were cheaper,
> but the amount of profit arcade games made, surely they could have
> afforded colour? And make the effort to squeeze a couple more chips in so
> we actually got maybe 5 or 6 colours all on the screen at once! Actually
> yeah I can see why they didn't bother, often there were very few objects
> on screen at all, or very few types of object, with multiples of them.

There's another reason - colour would have made the bit shuffling
*much* more complex - the ones with CPUs were running flat out as it was so
the games would have slowed down, as for the dedicated chips - they were
maxed out too colour would have been too much logic.

> Still I reckon colour would have stood out in the arcade. But maybe any
> screen at all did, and that was enough.

The original space invaders had a B&W screen with a gel filter at
the bottom to make the invaders change colour when they got close.
Strangely the screens were at the bottom facing up, what the player looked
at was a mirror at 45 degrees.

--
Steve O'Hara-Smith | Directable Mirror Arrays
C:\>WIN | A better way to focus the sun
The computer obeys and wins. | licences available see
You lose and Bill collects. | http://www.sohara.org/
Re: Learning PDP-11 in 2021 [message #409291 is a reply to message #409282] Thu, 24 June 2021 19:45 Go to previous messageGo to next message
Andreas Kohlbach is currently offline  Andreas Kohlbach
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On Thu, 24 Jun 2021 19:40:18 GMT, greenaum@gmail.com wrote:
>
> On Tue, 11 May 2021 11:29:54 -0400, Andreas Kohlbach <ank@spamfence.net> sprachen:
>
>> Apparently I can emulate a PDP-1 (from 1961?) in MAME, although MAME is
>> supposed to only emulate machines with a microprocessor as CPU. So
>> machines with i4004 (1971) upwards.
>
> Where did you hear that? I've never heard anything about MAME having
> some preference for integrated CPUs vs circuit-board ones.

If I only knew. Cannot verify my claim other than

| MAME can emulate many different central processing units (CPUs) and
| associated hardware.

from its Wikipedia page. May be I misinterpreted that as can *only*
emulate CPUs.

The other thing is that Gun Fight from 1975 existed in two versions. One
with discrete logic, and a newer version with a CPU. It's supposed to be
the first game ever using a CPU (microprocessor unit), and this IIRC the
oldest game MAME can emulate.

Another example is the popular Breakout from 1976, which isn't emulated
(due to not having a CPU?). Breakout II then from 1978 is emulated
(because it has a CPU?). That's where I drew my conclusions from.

There were many questions about the popular game Monaco GP and MAME. The
answer was always that MAME does not support this because it used TTL.

As morbid side note, 1992 the game Ayrton Senna's Super Monaco GP II was
released for some video game consoles. Not two years later Senna died in
a car crash.

> Though that said the "AM" stands for "arcade machine, they let the "M"
> for "multiple" take precendence over that way back when.

MAME merged with MESS (Multi Emulator Super System) but the new program
retained the name MAME (Multiple Arcade Machine Emulator).

> Eventually MAME will be able to emulate any machine that ever existed,
> including those MAME cabinets that people build. Including
> the Morse Code Key, and the bone for hitting other monkeys over the head with.

Games becoming more mechanical as you go back in time. I don't think you
can emulate any of these.

[...]

> Wow, pardon the long post!

No problem. Although trimming a lot (which I mostly agree to) I enjoyed
reading.

> Good ol' Usenet! You've got 6 more weeks to think about it, probably,
> so no worries. It's like the ooooold days must've been here, very
> little activity and conversations that stretch over however old
> long. Nice!

What happens in six weeks?
--
Andreas

https://news-commentaries.blogspot.com/
Re: Learning PDP-11 in 2021 [message #409306 is a reply to message #409285] Fri, 25 June 2021 10:21 Go to previous messageGo to next message
scott is currently offline  scott
Messages: 4237
Registered: February 2012
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Senior Member
Ahem A Rivet's Shot <steveo@eircom.net> writes:
> On Thu, 24 Jun 2021 19:40:13 GMT
> greenaum@gmail.com wrote:
>
>> I suppose B&W CRTs were cheaper,
>> but the amount of profit arcade games made, surely they could have
>> afforded colour? And make the effort to squeeze a couple more chips in so
>> we actually got maybe 5 or 6 colours all on the screen at once! Actually
>> yeah I can see why they didn't bother, often there were very few objects
>> on screen at all, or very few types of object, with multiples of them.
>
> There's another reason - colour would have made the bit shuffling
> *much* more complex - the ones with CPUs were running flat out as it was so
> the games would have slowed down, as for the dedicated chips - they were
> maxed out too colour would have been too much logic.
>
>> Still I reckon colour would have stood out in the arcade. But maybe any
>> screen at all did, and that was enough.
>
> The original space invaders had a B&W screen with a gel filter at
> the bottom to make the invaders change colour when they got close.
> Strangely the screens were at the bottom facing up, what the player looked
> at was a mirror at 45 degrees.

Which allowed a smaller cabinet footprint, IIRC.
Re: Learning PDP-11 in 2021 [message #409309 is a reply to message #409306] Fri, 25 June 2021 10:40 Go to previous message
Ahem A Rivet's Shot is currently offline  Ahem A Rivet's Shot
Messages: 4843
Registered: January 2012
Karma: 0
Senior Member
On Fri, 25 Jun 2021 14:21:59 GMT
scott@slp53.sl.home (Scott Lurndal) wrote:

> Ahem A Rivet's Shot <steveo@eircom.net> writes:

>> The original space invaders had a B&W screen with a gel filter at
>> the bottom to make the invaders change colour when they got close.
>> Strangely the screens were at the bottom facing up, what the player
>> looked at was a mirror at 45 degrees.
>
> Which allowed a smaller cabinet footprint, IIRC.

I can see how it would - very clever whoever came up with that! I
imagine the target footprint was that of the typical one armed bandit.

--
Steve O'Hara-Smith | Directable Mirror Arrays
C:\>WIN | A better way to focus the sun
The computer obeys and wins. | licences available see
You lose and Bill collects. | http://www.sohara.org/
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