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Allison's paltry collection

Oh, Allison, if you've the time, I wouldn't mind public or private post on how to dig up a PDP8 and get started, I just now feel I gotta sit down and grok the thing, seeing as how it's being mentioned in the same post as Tandy PC clones, which after all started as a clone of the PCjr.

The easiest way is KB1GMX at ARRL dot NET.

As to finding a PDP-8 well that could be harder or easier.

DECmate II/III are easy enough to find and used the 6120 Cmos
PDP-8 on a chip. Decmate-I (base decmate) was a larger flavor of a VT52 looking thing and used the earlier 6100 Cmos PDP-8 on a chip.
PDP- 8As are more common than earlier 8s but even then we're talking about some 35,000 or so. People have built 8s on FPGAs using VHDL
and even with TTL. Like I said it's stark in it's simplicity and scary simple in instruction set. Google PDP-8 and you find a load of sites on it.


Look at Doug Jones site and links.

http://www.cs.uiowa.edu/~jones/pdp8/index.html

http://research.microsoft.com/users/GBell/Computer_Engineering/

The latter site is Gordon Bells computer engineering text and a worthy read on computer design and archetecture.


Allison
 
>That TI card was rare to find. ;) I have three Ti99/4As with all the >trimmings.

I do recall the 99's having a PC-compatibility option, but I was referring to the TI Pro. The board for it had an onboard 8088, and presumably a 6845 (the main reason these things were incompatible), and a bios I guess. I have something like it for the NEC APC III. Haven't examined it or even played with that puter much.
All in all I like the Japanese computers most of all. In reading through those old Bytes, there were loads of them. All seemingly incompatible lol, but had a certain character. That's what makes these things fun. Who wants to go on a field trip?

>I call it time compression, happens when you exceed 30. Get really >nasty when you exceed 50.

I'm 38. I forget everything these days. Used to have a wicked memory.
 
patscc said:
Of course, missed all the posting action, anyway, Haven't even read it all.

Allison, I'm impressed with the MDS 220. Is that in anyway related to an MDS 800, which, from reading those pesky manuals, is the reference system for CP/M 2 ? But again, I've never actually played with one, but I do read.

The 220 was the next version with 5.25 inch disks. I have a MDS800 as well.

The 800 was used by DEC teminal systems group and was one of several used to develop... The VT100. That makes the MDS an old one and it's pretty cool to look at the white ceramic 8080 thats says "es" on it, as in engineering sample.

Allison
 
Chris2005 said:
>That TI card was rare to find. ;) I have three Ti99/4As with all the >trimmings.

I do recall the 99's having a PC-compatibility option, but I was referring to the TI Pro. The board for it had an onboard 8088, and presumably a 6845 (the main reason these things were incompatible), and a bios I guess. I have something like it for the NEC APC III. Haven't examined it or even played with that puter much.

yep oddball peice it was. I have the board, it's nonfunctional as is.

Chris2005 said:
I'm 38. I forget everything these days. Used to have a wicked memory.

That many years ago I was building radios and playing with transistors.
Then about 35 years ago a college friend had a Minuteman Missle computer a cylindrical thing that ate power like the sun and ran with a serial processor using a hard disk with fixed heads to act as serial shift register memory for both main memory and register memory. Never understood it back then, I'd likely hurt someone for it now. Guess that hooked me bad.

Allison
 
>Well, gee, Chris2499 1/2, you slay me with your logic. It's awfully hard >to talk programming and architecture with some one who's neither a >programmer, nor a systems architecht; you're clearly neither.

I done said I was neither. Just a punk. What the hell is this 2499 1/2 stuff?
Did you perchance mean 2004 1/2?

>Then, you also slay me with your brilliant use of the 8048/8051 >microcontroller family. So ? They're not 8086 compatible, certainly don't >run DOS. So what you're saying is that there's lots of SBC's running non->80x86 processors. Which is a 180 from what you said a few posts ago. >Brilliant !

Awwww thanks man, you're too kind

>For every concrete example mentioned, you come back with "well, >there's a thingie, and then sorta, but I remember, and I did, and I >didn't, and all this stuff was available. And this doodie, and that >doodiedadie" etc.

Doodiedadie? Wotsa doodiedadie?

>Oh, darn. Now you're back to remembering code, even though you're >not a programmer.

Anyone with the mind to can pick up some books and learn some coding. It's a free country. No, not a bona-fide programmer, neither a doodiedadiehead either.

>Well, okay, why don't you post some of that sample 'wierd' code for >accessing C64 video memory, and then I'll post some code for >accessing the equally wierd organization of EGA memory; this might >take a while, since I'd probably have to write it, and this is certainly >from the way back machine. To top it all of, you mention that the 'Snow' >problem of CGA had been solved. Go look at some of the code required >for that. But there I go again.

Yup, there you go again. I don't have that book anymore, but I'll find it and get back to you. And I DID SAY the weird code came from a book, my own brute force method was lacking the elegance of boolean logic.
You had to write to memory during the vertical retrace interval, that's all I know.

>And of course, since you say something the other about C and >assembly, but aren't a programmer, I won't point out to you that I >actually *was* talking about C regarding the effects of a system's >architecture on a language, but I guess you missed that one.

I don't think I missed it, but I am missing the point here. Whatever lol.

>I guess, since no one does assembly anymore, there's no point in >pointing out to you that 2 lines of anything doesn't mean it's faster then >6-10 lines of the same thing. Ever hear of macro expansion, but then, I >guess not, since you're not a programmer. Okay, scratch that.
>Examples, give us examples. As they say, you can't run vapourware.

Generally speaking, or I would think the vast majority of the time, 2 lines of code takes fewer machine cycles than 6-10. You don't have to be an architect to know that.
No, I'm not really sure what a macro expansion is. And I don't know what examples you're looking for. Yawn.

>>Why, even though I'm a Win32 api programmer( for my sins, I guess, >please don't think any less of me, I gotta earn a living somehow ), do I >find myself disliking Wintel more with each post on this thread ?
>Your beloved 80x86 family is one where the execution time per >instruction is not constant, it depends on the operands, the addressing, >what segments are being used, on the other hand....
>Oops, forgot, you don't do hardware, so just ignore that,

I hear God is forgiving all kinds of stuff these days Pat. Even being a non-stop doodiedaddiehead.
Ok, but I should be ignoring ever last bit of this.

>Somewhere in there, you're also ranting about PDP-8 stuff. I don't really >know anything about them, but from following the posts, I get the >impression there where a bunch of machines in that model line. This >seems to disturb you. Perhaps you aren't familar with the Tandy 1000, >Tandy 2000, and Tandy 3000 series ? And how many Tandy 1000's >where there ? Do you know ? Does anyone know ?
>So who cares there's a bunch of machines called PDP-8 or Tandy 1000 ?
>All that says is that both where popular, and that marketing departments >ran with it.

What? I'm not familiar with the Tandy's? I owned them all Pat. I have a yahoo group sort of devoted to the T2K. You're welcomed to join. It really, REALLY needs some participation. No flaming the group owner though, cuz I'll boot yer ass right out.

>I think part of the problem is that I've gotten my information from >reading manuals. Books. Chip datasheets. That kind of stuff. From >reading Allison's posts, it would seem that she's written most of the >one's I've read.
>It seems as if you get most of your information from advertisements, or >perhaps friends, maybe even from vapourware, so I guess I shouldn't >be to critical you can't seem to come up with any real examples of what >you're talking about.
>Even your mention of IBM and the 68000, who was it that actually >mentioned the IBM series involved ? Certainly not you. And who >mentioned why they weren't exactly a stellar sucess, again, not you.

No. I don't get it from any of those sources. A little gofer comes to my window in the wee hours and tells me all this shit. As reliable a source as any if you ask me.

>If you seriously think there aren't any ASIC's in your Tandy 2000, you >might want to pull it apart again and look all the stuff in there up. >Perhaps you might even discover what a 8255 is.

I know for a fact there are no application specific ic's in my model 2000.

>Your mention of clones, so what ? That certainly wasn't with IBM's help, >they tried to sue the pants off anyone that developed their own BIOS.

Put yourself in their shoes. You would take pains to protect your ideas and assets. I REALLY KNOW THIS, judging by how pissed of you're getting over this whole affair.

>You keep saying how great early PC's were. I was there too, and I >remember the stuff somewhat differently, I guess. Define better. Give >us some specs, perhaps even some benchmarks, you know, all that >geeky stuff we all love, and then maybe we'll see your point.

whatever

>Bloated code has a whole lot of other reasons behind it, Windows, for a >start. Before you accuse me of "Windows bashing" , or "PC bashing", or >whatever you're going to accuse me of, gain some experience in >programming, and systems design, and then come back, do some >programming in Windows, and then we'll talk about the causes of >bloated code.

I know the mere basics of W32 programming. I have friends in the industry. They say there's a lot of doodiedaddieheads writing this stuff.

>See, though, there's that magic phrase again, "They say..."
>So let's invite the mythical "They" to the party, and see what they have >to say, and let's see their post.

Unlike you and me Pat, they have a life. They're won't be coming around.

>Why not post some examples of what you're talking about ? Post part >numbers, card models, even manufacturers would be nice. Hey, >personally, I'd even settle for the planet all this great stuff came from( >don't bother replying, it's a rhetorical question)

It's all on Uranus Pat. But don't ask me what the rocket that will take you there is using for hardware. Ask Allison, she'll know for sure.

>So what's up with lol, anyway ? Can I let you in on a little secret ? I >never quite grokk'ed lol. I assume, when you don't terminate a line with >lol, you're not lol. So what are you, then ? Smirking ? Nattering ? >Simpering ?
>But, then, I mispell, the gods know why, you lol, only you know why, so >I guess it all balances out.

I do that so people know when I'm kidding around. Because there always seems to be people like you who have a fit over online posts and whatnot. But somehow people like you still miss the point.

>Hey, why don't you let Sam post something ? I'm sure we're all >interested in the Epson "thingies" you mention, but prefer more concrete >information like "Model"
>See, I just don't grok "thingie"
>"Thingie" is what I get from my purchaser when I need to order >something. Are you in procurement ? If yes, then this is a feud for life.

Yes Pat, I do have the feeling this isn't going to end for quite some time.

>Foo, your Tandy is your garage. Don't see you pulling it out, grokk'ing >the board, before you post about 'it's all off the shelf'
>Mine was in the basement, pulled apart, until I grok'ed the system >board, and felt fairly confident in saying the 2000 series is just chock-full >of ASIC's.

Pat, it was my first freaking puter. It's all Intel and ttl logic. You never owned a 2000. Prolly a totally different model.

>You know, it figures you'd grok the HP49 instead of the HP48gx, guess >all that RPN scared you off ? Or perhaps your instructor realized that the >solver on the 48/49 series could probably do your entire test for you ?
>Oooh, sorry, that was a low blow, shouldn't have said that. I also >solemly swear to not mispell for the next line or so.

I didn't need a calculator to do a test for me you friggin rube. And the reality is the 49's would probably do the test faster. And I want a 48gx too *no longer made*, they're pricey when you can find them. Yes, I don't particularly care for RPN.

>Shoot. I previed the whole ting, looks like I didn't get in enough types. >Oh, well.

Skeery. How old did you say you were Pat?
 
No, I meant 2499 1/2. If you can't figure it out, maybe your gopher can tell you. Anyway, you're right about one thing, this thread has turned into a flame, so I think the easiest way out of it is if I just ignore your posts, which shouldn't be too hard. I don't really care if you ignore mine or not.
So, you can tell all your friends you won, or pound your manly chest, or whatever it is you do.

patscc
 
Allison said:
C64, who's video memory was layed out really strange, which I would implement in 6-10 lines of of assembly, later reading could be accomplished in 2 using "weird" logic.
I assume you're referring to hires bitmapping. It is layouted in segments of eight bytes, where each byte corresponds to eight horizontal dots:

x1-8y1 x9-16y1
x1-8y2 x9-16y2
..
x1-8y8

etc. There are 40 columns (320 pixels) and 200 rows in total. Unless I have screwed up, the address in memory becomes:

POKE BASE+INT(X/8)*8+(Y AND 248)*40+(Y AND 7),2^(7-X AND 7)

I could probably do this in assembly, but it would be far more than 6-10 instructions. Besides it is almost 1 AM here, so that'd have wait for another day.
 
where to find a PDP-8...

where to find a PDP-8...

Hey Pat, let's just be best pals from here on out. :)
And I was told by the dudes that had the PDP-8/e at the show that many of those were used in CNC applications, although in those environments, the boards get really mucked up with cutting fluids and swarf. You'll need help moving the things, and I already have the experience, so feel free to call on me LOL LOL - (see, that's a funny, we probably don't live near one another). But maybe you were referring to the later, lighter models Allison was referring to. I hope to God for your sake. That sob was pretty big!
 
Some things stand out in these posts that as a mechanic friend of mine used to say, "all this info hurts my head".

My question to Allison is what sources she has for:

>I call it time compression, happens when you exceed 30. Get really >nasty when you exceed 50.

I've always had a view that it was natural that your perception of time would accellerate as you get older. Just as a year seems like an eternity when you're 10 years old and it's 10% of your life experiences. Days and weeks zoom by as I approach 70 and of course my eventual demise.

I haven't seen any scholarly research on this. Is it available ? Or should
I just forget it take a toke of good time-expanding Ganga.

>I call it time compression, happens when you exceed 30. Get really >nasty when you exceed 50.

Chris confessed a problem and if I were him I would check it out. He
might have some early symptoms of such as Altheimers.

>I'm 38. I forget everything these days. Used to have a wicked memory.

You're still quite young. As you get older it is a memory storage and accessability problem. You have many more memories to sift thru to find
the revelent information and of course many more qualifiers to judge an accessment of it.

There was mention of the DEC Pro 350. I still haven't been able to make
a boot disk that will get me past the security protection on the HD. There
are numerous methods involving the RT11 or POS bootdisk. Unfortunately I have neither and have been unable to generate one with Putr. I would
gratefully pay any shipping costs to anyone who would send me one.

Thank You

Lawrence
 
Hi Lawrence...it may have been an exaggeration to say "I forget everything". I will say this though - I notice these days that my remembrance of things is often "warped" - I could sware up and down that when so and so said such and such they said it with a particular attitude or whatever. But when watching say a movie for a second time, I'll notice that my impression of actor's "attitude" in a particular circumstance is different then what I was able to recall. The sort of thing probably happens to alot of people though.
Also, if you have too much going on in your mind, some stuff will get "force off the stack". I remember reading about the guy who invented television, his name escapes me at the moment lol, who was so absorbed with his work, his whole body would pulsate as if his adrenal glands were working overtime. I often notice this sensation when I'm sitting cross-legged on a bed. Exercise, diet, and relaxation, which seemingly is tough to find these days, woud be the cure for it I suppose. I'm not working on any big invention though right now lol.
 
carlsson said:
Allison said:
C64, who's video memory was layed out really strange, which I would implement in 6-10 lines of of assembly, later reading could be accomplished in 2 using "weird" logic.
I assume you're referring to hires bitmapping. It is layouted in segments of eight bytes, where each byte corresponds to eight horizontal dots:

x1-8y1 x9-16y1
x1-8y2 x9-16y2
..
x1-8y8

etc. There are 40 columns (320 pixels) and 200 rows in total. Unless I have screwed up, the address in memory becomes:

POKE BASE+INT(X/8)*8+(Y AND 248)*40+(Y AND 7),2^(7-X AND 7)

I could probably do this in assembly, but it would be far more than 6-10 instructions. Besides it is almost 1 AM here, so that'd have wait for another day.

I didn't write the quoted stuff. never had a C64.

Allison
 
Micom 2000 said:
Some things stand out in these posts that as a mechanic friend of mine used to say, "all this info hurts my head".

My question to Allison is what sources she has for:

>I call it time compression, happens when you exceed 30. Get really >nasty when you exceed 50.

I've always had a view that it was natural that your perception of time would accellerate as you get older. Just as a year seems like an eternity when you're 10 years old and it's 10% of your life experiences. Days and weeks zoom by as I approach 70 and of course my eventual demise.

Your completely correct. However the perspective of looking back has the
problem of the events of the years getting munged closer together. It's
makes timesense looking back compressed, IE: was that 1982 or 83?


There was mention of the DEC Pro 350. I still haven't been able to make
a boot disk that will get me past the security protection on the HD. There
are numerous methods involving the RT11 or POS bootdisk. Unfortunately I have neither and have been unable to generate one with Putr. I would
gratefully pay any shipping costs to anyone who would send me one.

If I still had one around I'd give it to you.

Allison
 
Re: where to find a PDP-8...

Re: where to find a PDP-8...

Chris2005 said:
Hey Pat, let's just be best pals from here on out. :)
And I was told by the dudes that had the PDP-8/e at the show that many of those were used in CNC applications, although in those environments, the boards get really mucked up with cutting fluids and swarf. You'll need help moving the things, and I already have the experience, so feel free to call on me LOL LOL - (see, that's a funny, we probably don't live near one another). But maybe you were referring to the later, lighter models Allison was referring to. I hope to God for your sake. That sob was pretty big!

Rack mounted systems tended to look big. There is likely a fair amount of daylight in there. the 8e box itself is 11hx19wx28d and that's the CPU, mem and IO. Disks back then were about as large.

Allison
 
PDP-8/e and such

PDP-8/e and such

go to: http://www.pdp8.net/
The 4th unit from the left is the one that Dave had at the show.
I found a huge stash of old puters. In one corner of this mess, there sat a DEC looking monitor, and a crate of manuals and possibly software. I should have grabbed it then, but got to take a run back there maybe this week. Problem is, if any of that stuff even works, how do you archive it? There are legitimate DOSish disks I can't even read with WinImage, I can't expect too much luck with that stuff. Any suggestions? The same goes for about 50-100 disks I got somewhere else, with UNIX stuff belonging to an AT&T 7300 system, 68010 based. They are supposedly readable in a pc, but I can't imagine WinImage being able to handle (some of) them either.
It would be nice if someone "catalogued" the disk imaging utilities out there. I've heard of a few others, but don't have any experience with any.
 
Re: PDP-8/e and such

Re: PDP-8/e and such

Chris2005 said:
go to: http://www.pdp8.net/
The 4th unit from the left is the one that Dave had at the show.

I've seem many like that in the flesh. Some are not so pretty but thats the fun of making them go again. Some like PDP-12s are truely scarce
and even finding part of one is an event.

Chris2005 said:
I found a huge stash of old puters. In one corner of this mess, there sat a DEC looking monitor, and a crate of manuals and possibly software. I should have grabbed it then, but got to take a run back there maybe this week. Problem is, if any of that stuff even works, how do you archive it? There are legitimate DOSish disks I can't even read with WinImage, I can't expect too much luck with that stuff. Any suggestions? The same goes for about 50-100 disks I got somewhere else, with UNIX stuff belonging to an AT&T 7300 system, 68010 based. They are supposedly readable in a pc, but I can't imagine WinImage being able to handle (some of) them either.
It would be nice if someone "catalogued" the disk imaging utilities out there. I've heard of a few others, but don't have any experience with any.

OK first step is PCs will be useless except as maybe a terminal and for electronic pictures.

First gather everything that looks related and leave nothing tochance that it might be. Pdp-8s are very different in that they are 12bit words. So software and media will reflect that difference all the way. As to archiving it the easy way is work with other PDP-8 system owners with working hardware. They can read and archive, or they may have it online already
negating the need to save content (unless unique). Media you always save as it can be scarce or costly, especially RK05 packs for the 8.

The PDP-8 had several possible OS for it, everthing from simple sungle user BASIC or FOCAL loaded from paper tape to OS/8 and MUMPS and
even SRT-8 (real time kernal). Most of those are on the net as both binary and source.

The same approach for other vendors systems, find users of those and work as a group as docs and working systems are key to preserving old hardware.

As to restoring the systems... there are many sites for PDP-8 and others
that maybe useful to the fine detail level. Each vendors machine depending on vintage will likely have a watch for this or that pointed out.
For example PDP-8s frequently had foam on the inside top cover that
decays to a mess over time and must be removed before powering.
Then for machines that have not been powered in many years there are
things to test/watch for on first power up lest the PS self destruct.

FYI: My PDP-8f looks much like the 8m in those pictures. If you go to
Megan's site she has a series of pictures from a move of PDP-8 systems.
And the 8F with "71" in pinkish marker on the front is mine now. That was
a similar group of systems as a group shot. It's been cleaned up and power supply fixed. I like it as a plain no tty front pannel play with machine. I have IO for it but there are fun programs for music via radio (switching noise) and inchworm (patterns on the lights). Most are a few dozen words at most.

My 8f before cleanup and repair.
http://world.std.com/~mbg/move_step21.jpg

The system is an 8f (short omnibus box) with 16kw of core and EMA plus two serial IO cards. At some point I plan to make a IDE interface for it.
It's 19wx8.5hx16.5d for scale. This is a rack mountable box so the front
pannel is an easy inch wider than the box where the hardware is.


Allison
 
dec software

dec software

So let me ask you though - is it impossible to read these things in a PC floppy drive? The point is well taken that I should turn them over to someone with DEC equipment (I'm not saying this stuff is for the PDP-8 though - truth is I don't really know). But I'm finding that there's alot more compatibility than I ever would have expected between drives and controllers and even formats. One guy at the show had IBM style Teacs plugged into his TRS-80 model 3/4. This personally surprised me. Then there's the ability to plug HD 3/5" drives into a Peanut (or any PC/XT for that matter) - www.micro-zone.com.
I remember there being another utility that could read virtually anything, though I never tried it. oldskool.org I think.
Here's other links:
http://www.bookcase.com/library/software/msdos.util.disk.html
ftp://ftp.simtel.net/pub/simtelnet/msdos/diskutil/fdfrm18.zip
here it is: http://www.oldskool.org/disk2fdi
 
Re: dec software

Re: dec software

Chris2005 said:
So let me ask you though - is it impossible to read these things in a PC floppy drive?

Conditional maybe. Read may mean image copy at most or possibly
more. You can bet file formats are different. within a family of systems
or a vendor it's often less a problem but generally PCs are outside though
sometimes a useful tool.

Chris2005 said:
The point is well taken that I should turn them over to someone with DEC equipment (I'm not saying this stuff is for the PDP-8 though - truth is I don't really know). But I'm finding that there's alot more compatibility than I ever would have expected between drives and controllers and even formats. One guy at the show had IBM style Teacs plugged into his TRS-80 model 3/4. This personally surprised me. Then there's the ability to plug HD 3/5" drives into a Peanut (or any PC/XT for that matter) - www.micro-zone.com.

Why not? The drive interface standard for 5.25 and even 3.5" floppies
are fairly consistant since the days of the SA400. What likely to be variable is FDC used, on disk format, File format, number of heads
(one side or two) and number of tracks. Thats enough ground to cause havoc.

However most of my active systems starte with 5.25" drives of different flavors some even 8". One thing I did was to install 3.5" floppies to standardize on media. For boxes like my Ampro, Kaypro and S100 crates
that was easy. It avoids the fifty differnt formats and media problems
to an extent.

Chris2005 said:
I remember there being another utility that could read virtually anything, though I never tried it. oldskool.org I think.
Here's other links:
http://www.bookcase.com/library/software/msdos.util.disk.html
ftp://ftp.simtel.net/pub/simtelnet/msdos/diskutil/fdfrm18.zip
here it is: http://www.oldskool.org/disk2fdi

There are disk tools, specialized controllers that are flexible and the like.
The noteable one was the Catsweasel as it can interface with 8/5.25/3.5
and from what I understand read most if not all.

The however part. It helps to know what you have and how it's structured before doing anything. For example DEC used many
different 5.25" formats but the base on disk format was one of three
possible (Vt180 160k SSDD, RX50 <Decmate, rainbow, PDP-11, Pro, VAX> and RX53 some version of DECmateIII, Rainbow and VAXmate
<PC dos 1.2mb>) and those worked with Sa400 like drives (Vt180 SSDD), RX50 was Teac fd55f (80tr SSDD), and Teac FD55GFR (80tr DSDD). Tapes and other media are a different set of cases. If it
were 8" media DEC had two drives RX01 (SSSD) and RX02 (SSDD)
and RX02 is not readable on most other non DEC hardware. RX01
was IBM standard single density. Both drives were used/interfaced
on all DEC systems that could accept an interface module (PDP-8,
PDP11s and most Vax11/7xx and Qbus microVAXs). That's just
a sample. It also helps explain why I for example don't touch certain systems due to diffusion of effort.

Hope this helps answer some of your questions.

Allison
 
onto other topics...

onto other topics...

Allison, what do you think of SGI and Sun puters. I've always had a hankering for an Indy, though it may just be due to the way it looks.
 
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