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-   -   IBM PCjr and Tandy 1000, the almost PC compatibles. (http://www.abandonia.com/vbullet/showthread.php?t=46198)

Neville 24-09-2018 04:31 PM

IBM PCjr and Tandy 1000, the almost PC compatibles.
 
I already mentioned these two computers in a previous guide, but since many DOS games offer some kind of support for them, I think a more in-depth explanation could be of interest to the readers.

The IBM PCjr.

https://i.imgur.com/m2JhI9S.jpg?1

When IBM launched the first PC models around 1981, they had little in common with the PC clones we use these days. They employed MDA and CGA display cards, 8088 CPUs running at 4.77 Mhz and could have as little as 16 Kb. of RAM. Their prize was around $1.565 and they found success in office use, especially after the release of spreadsheet software.

By the end of 1983, IBM announced the PCjr. The PCjr was designed with the intention of becoming a home variant of the IBM PC, competing with other computers such as the Commodore 64, the Atari 8 bit family or the Apple II.

The PCjr would use the same CPU 8088 @ 4.77 Mhz of the IBM PC, but changes were made to the display and sound systems. The CGA display now supported several 16 color modes, and the PC speaker had three sound channels rather than one. The first "King's Quest" game by Sierra Online was ordered by IBM as an example of a game taking advantage of these extra features.

However, when the PCjr was finally released in 1984 it was poorly received. There are several reasons for that:

- It was competing with 8 bit computers, which were much cheaper than the PCjr, which sold at $669, and already had an stablished market.

- IBM had promised a fully PC compatible machine. However, with only 128 Kb. of RAM and limited expansion possibilities, many IBM PC programs wouldn't run in the PCjr.

- Accesories such as the wireless keyboard were widely criticised. Originally, the PCjr was shipped with a rubber keyboard that made typing at a reasonable speed almost impossible.

In 1985, IBM stopped manufacturing the PCjr after 250.000 units had been sold. IBM would not try to sell a home-oriented PC until the PS/1 in 1990.


IBM PCjr legacy and emulation.

Or the reason you may be interested in this system.

- Cartridge games: A handful of games were released in this format for the PCjr. Many of them were also released for DOS or in PC Booter format, but won't run in regular PCs.

- PC Booter games: These type of games were designed to run by booting the computer with their disks. This allowed for games to use different OSes than DOS or to implement their own copy protection schemes.

Some games from this era had either different CGA, PCjr and Tandy releases or are PCjr / Tandy exclusive, such as "Ghostbusters" or "Pitfall II". You may need an specific version to obtain PCjr benefits.

- Regular DOS games with PCjr support: This is the most common situation. A DOS game released during or after the PCjr era that has some kind of PCjr support. Normally this will mean plain CGA graphics, but some games such as "Pit Stop II" or "Super Boulder Dash" will show better graphics if they detect a PCjr machine.

https://i.imgur.com/JktxdY1.png https://i.imgur.com/wm2Epc7.png

https://i.imgur.com/8fwaWXi.png https://i.imgur.com/9ADIWLj.png

"Super Boulder Dash" and "Montezuma's Revenge" in CGA and PCjr modes.

DOSBox can run PCjr software by setting machine=pcjr. It can also run PCjr cart dumps (files with a JRC extension) with the command BOOT name of file.JRC.

PCem offers one profile to run a PCjr machine, but doesn't support (yet) booting from a cartridge image.

Neville 24-09-2018 05:42 PM

The Tandy 1000.

https://i.imgur.com/CEu61jX.jpg

The Tandy 1000 was an economic PC clone developed by Tandy Corporation and sold in their Radio Shack stores. It's hardly known outside the United States.

The first models were presented in november 1984. Since they were built around the IBM PCjr architecture and that computer was a flop, Tandy soon dropped any mention to the IBM PCjr. in their advertising. Early Tandy 1000 computers kept using the same components (CPU 8088 @ 4.77 MHZ, a CGA graphics adapter with some extra 16 color modes and a three-channel PC speaker) while newer models added a sound DAC, 80286 and 80386 CPUs and even VGA and SVGA graphic cards.

Many games from the era claim to be "Tandy compatible" or include mentions to "TGA Graphics".

The Tandy 1000 computers usually shipped with a customized version of DOS and Tandy Deskmate, a program environment. In many models the OS runs from ROM rather than from disk.

https://i.imgur.com/GkukLI1.png

Tandy Deskmate v3.05.

In a way, the Tandy 1000 were what the PCjr should have been. They ignored the cartridge ports, added more RAM and made the computers easier to expand. Between this, the ubiquity of the Radio Shack stores and a prize of $1.200 (higher than the IBM PCjr, but lower than the rest of PC compatibles) the Tandy 1000 line of computers was successful until 1990, when the game developers started moving towards VGA graphics.

The last Tandy 1000 models were discontinued in 1993.


Tandy 1000 legacy and emulation.

Unlike the PCjr, there isn't much Tandy-specific software. Also consider that games designed for the PCjr won't necessarily run on a Tandy 1000. They are, after all, different systems.

On the other hand, given the popularity of the system many games before 1990 offer some kind of support for the Tandy 1000 or claim to be "Tandy compatible".

The lower spectrum of these games are those which, upon detecting a Tandy computer, will run in 16 color mode mode and little else. This is the case of "Secret of Monkey Island" or "Indiana Jones and the Last Crusade". These games were launched in 1989-90 in separate 16 and 256 color versions. Tandy 1000 users had to use the 16 color version.

https://i.imgur.com/4IomVoy.png

"Indiana Jones and the Last Crusade" shows the same graphics under EGA and Tandy 1000 computers.

Other games will play better sound if a Tandy 1000 is detected. Better sound than a plain PC speaker, that is. That's the case of "Arkanoid" or many early Sierra Online games, such as "King's Quest" I to III, the first "Leisure Suit Larry" and the first two "Space Quest" games. All these make good use of the three channel PC speaker.

And finally, there are a few games with that acknowledge Tandy 1000 users with extras such as 16 color graphics (as opposed to plain CGA), different palettes and extra sounds.

A few of these are "Arcticfox", "Shangai" (which show 16 color graphics for Tandy users only), "Falcon" (which had an specific Tandy version), and "Outrun" (extra voices).

https://i.imgur.com/UBBEmhQ.gif https://i.imgur.com/KgWPWgQ.png

https://i.imgur.com/hL95F2Q.png https://i.imgur.com/j6zgT3k.gif?1

"Shanghai" and "Arctifox" running under CGA and Tandy modes.

As for emulation options, DOSBox is easily the best one. Use the setting machine=tandy and you are all set. Even the Tandy DAC of later models is emulated.

PCem also offer good Tandy emulation, but in this case you are limited to the models with 8088 and 8086 CPUs.


Links.

MobyGames list of PCjr cartridge games.

MobyGames list of games with PCjr / Tandy graphics support.

MobyGames list of games with PCjr / Tandy sound support.

MobyGames list of games with Tandy DAC sound support.

VOGONS thread about games with PCjr / Tandy support.

Nerdy Pleasures: IBM PCjr and Tandy 1000 games.

Neville 30-09-2018 02:16 PM

I've decided I'll use this thread to talk about peculiar PC machines I find about using emulation. My first PC was already 486/66 clone with SVGA graphics and a Sound Blaster, so I was a sort of late arrival to the PC world. Stuff like the CGA / Hercules wars or earlier PC clones are quite new to me.

And another thing: could anyone change the Tandy 100 bit in the title for Tandy 1000? It's a very embarrasing typo.

Neville 30-09-2018 02:48 PM

First of all, maybe I should explain why there are so many PC clones... see, when IBM made their first PC model (the 5150, released in august 1981) they built it using off the shelf components, and they also allowed other manufacturers to sell their own parts and peripherals. The only part that IBM kept copyrighted was the BIOS, imagining that other PC manufacturers would have to pay for it for years. Unfortunately for IBM, the PC BIOS was quickly reverse-engineered by brands like Compaq and American Megatrends.

Now, today I want to mention two Amstrad computers. The first is the Amstrad PC512 from 1986. Apparently it was very popular in Europe, to the extent this model and the 1640 may have been to Europe what the Tandy 1000 and variants were to the USA: the first affordable PC compatible for many people.

http://i.imgur.com/Lqhu8kw.png

The specs are not too different from IBM PCs of the same era: 512 Kb. RAM, CPU 8086 @ 8 Mhz. and a CGA-compatible Amstrad graphics card, with an extra 640x200x16 graphic mode.

That extra graphic mode is the first curiosity. A few games claim to use it, such as "Maupiti Island" or "Frank Bruno's Boxing", but my guess is that it was especially included for use with the GEM desktop.

https://i.imgur.com/7wdRDXa.png

Maupiti Island, showing 16 colors.

The PC1512 came with three different startup disks. The first one, you guessed, was MS-DOS 3.2. The second one was a different DOS, DOS Plus, a DOS Variant developed by Digital Research and based on CP/M, an earlier OS shared by many 8 and 16 bit computers.

And the third disk was GEM, a variant of the desktop that was used in other computers at the time, most notably the Atari ST. This variant was also developed by Digital Research.

https://i.imgur.com/xKbVx0a.png

A PC1512 running GEM.

However GEM wasn't a big success in the PC market, and people soon moved to other software desktops, such as GS/OS, Deskmate and Windows.

The 1512 had a successor, the Amstrad PC1640, this time with 640 Kb. of RAM and an EGA compatible display card.

More rarities? Well, take a look at the pripherals on that first picture: the mouse (and I think the joystick as well) is not standard, but Amstrad's specific. It has a different connector and won't work unless you use the Amstrad drivers.

Well, at least you can emulate the whole thing using PCem.


The second Amstrad model I will mention this time is the Mega PC:

http://i.imgur.com/1ovgzFp.png

It's a PC compatible with a 386 CPU launched in 1993 lanzado en 1993. It's main appeal is that it has... a Sega Genesis / Mega Drive embedded. I can't possibly imagine who had the idea, but if you want a rare PC clone, you can't go much weirder than this one.

It's also a PC that brings me bad memories, because I accidentally destroyed one of them. I was in college at the time, and this machine was the one me and my friends we used to type our college works. I was told by the owner not to switch off the monitor (IIRC it was a custom one, the machine wouldn't work with regular PC monitors) because it was on its last legs. However, the computer crashed and out of habit I switched off both PC and monitor. From then on the monitor would only show a delicate violet light, but neither characters nor graphics. Damn.

The Mega PC likely didn't have much of an impact. By 1993 386-based PCs and the Sega Genesis / Mega Drive were likely at the end of their commercial lives.

PCem does emulate the machine, but only in regards to its PC side. For the Genesis / Mega Drive there are plenty of emulators to choose.

Smiling Spectre 01-10-2018 12:19 PM

Quote:

Originally Posted by Neville (Post 482819)
And another thing: could anyone change the Tandy 100 bit in the title for Tandy 1000? It's a very embarrasing typo.

Can't author - you - do it? Hmm. Strange.

I renamed it for you.

Neville 01-10-2018 01:04 PM

I tried using the "advanced mode" and couldn't do it myself. Thank you.

Smiling Spectre 02-10-2018 06:18 AM

It's in Thread Tools - Moderation - Edit Thread. I thought, it's accessible for thread author. Seems, no. Ok.

And you are welcome.

Neville 07-10-2018 02:35 PM

Today I'm gonna talk about the IBM PS/1 line from 1990, and more especifically the 2121 model.

The IBM PS/1.

http://i.imgur.com/4W0TFYw.jpg

The first PS/1 model was the 2011, with a 80286 CPU @ 10 Mhz and VGA graphics. It was followed by models 2121, 2133 and 2155, with 386 and 486 CPUs. The PS/1 line was an attempt from IBM to re-conquer the domestic market, something IBM hadn't tried since the flop of the IBM PCjr in 1984.

I haven't found much information on if they were succesful or not, but since the line sold until 1994, when they were replaced by the Aptiva models, I deduce they were.

So, what is so great about this PCs? In my opinion, what makes them especial is the desktop IBM included with them. Is made up of four screens, and through the mouse the user can access several options, from an overview of the system to a tutorial, Microsoft Works and even several on-line services.

https://i.imgur.com/sBxs8Dv.png

https://i.imgur.com/NXIVj64.png

This desktop system is built over DOS 4.01 and may have been introduced as an answer to Tandy Deskmate or GEM. As we've seen, other computer manufacturers used those programs as "desktops" for their users.

In some PS/1 models, DOS was loaded from ROM, just as in the Tandy 1000 computers. This makes me think IBM had the Tandy 1000 competition in mind when they released the PS/1.

Another curiosity is that some PS/1 models didn't include ISA expansion slots. For those, IBM marketed a sound device, the PS/1 Audio Card.

http://i.imgur.com/QQYh2fB.png

It was, of all things, a three channel sound generator similar to the one provided with the IBM PCjr and the early Tandy 1000 computers. Depending on the source, the card could include a DAC for digital sounds. No need to mention, this was a rather outdated device by 1990. By that time both AdLib and Sound Blaster cards were widely available.

Emulation.

You can forget about using regular DOSBox in order to emulate the IBM PS/1, since it doesn't allow for specific computer models except for the IBM PCjr and the Tandy 1000.

However, you can use Ykhwong's DOSBox build, which does emulate the PS/1 Audio Card.

Here's a list of games with support for the PS/1 Audio Card.

If you want the full experience of using a PS/1, you will need to use PCem. And not only that, you'll need the system disks that came with every model. Without them, you'll get the four screens menu, but you will be prompted for a disk everytime you click on any of them.

Personally, I was able to find the system disks for the 2121 model, and that's what you are seeing on the captures.

Neville 07-10-2018 07:06 PM

This pretty much sums up my experience with PCs that weren't PC clones... if anybody wants to talk about specific computers they used and, if possible, give PC emulation tips, I think this is the thread to do it.

This also means I should have made up a better / more inviting title, but right now I can't think of any.

Rogue 16-10-2018 01:56 PM

I tried IBM's business OS - CP/M-86 and older versions of DOS on first couple of models. PCEM made it all possible. :OK:

Neville 16-10-2018 02:14 PM

I've been hearing about CP/M for ages, but I've only used under the Amstrad PCW emulators. If I understood right, that OS was a precursor of DOS and CP/M programs could be run in several computers as far as they didn't include graphics.

Rogue 16-10-2018 02:55 PM

Quote:

Originally Posted by Neville (Post 482920)
I've been hearing about CP/M for ages, but I've only used under the Amstrad PCW emulators. If I understood right, that OS was a precursor of DOS and CP/M programs could be run in several computers as far as they didn't include graphics.

I think it CP/M came after DOS, like half year - year later.

This is how I find what I like to emulate, like some wired setup computer wise or software wise - I read old PC Magazines from 80s and then I hunt software / emulator to check it out. :smile2:

For example, this kind of magazines: https://archive.org/search.php?query...r%3A%221980%22

Neville 16-10-2018 04:03 PM

CP/M coming up after DOS? I guess it's possible. I used 8 bit computers before PCs, and sometimes I find hard to reconcile that PCs were a thing as early as in 1981.

I also like to browse older magazines... I was incredibly happy when I found all numbers of Micromania -the local computer magazine- had been preserved as PDFs. However, when I tried using them as a guide for must-try games I had to stop. It's incredible how many of the games they show in the news section ended up in development hell. As for the reviews, they are often hit and miss. They tended to give very high ratings, and to ignore obvious problems with major releases.

Rogue 17-10-2018 11:34 AM

Not CP/M as os, but one made for IBM PC.

I grow up with 8 bit computers as well, and I was reading about PCs, but nobody I knew had one, as they were way to expensive for my country of origin. Once i moved to Amiga, I still have one at home and emulate it a lot.

Only thing I was not successful installing/emulating was AIX for 386. I have OS, but it is very hardware specific and I was not able to install it.

I do have one server to play with (Aix 5.3) and we have 2 servers in production (AIX 7.1). It is my favorite *NIX system, right after FreeBSD.

Neville 17-10-2018 12:55 PM

Quote:

Originally Posted by Rogue (Post 482928)
Not CP/M as os, but one made for IBM PC.

Yes, I undestood. CP/M for other systems has been around since the 70s, or so I've heard.

Never heard of AIX before... to be honest I've only used Unix / Linux builds a few times, and Ubuntu was the one I preferred. Unless you count Android, of course.

Also never tried OS/2. From the included instructions in some games, it sounds difficult to set up.

As for Amiga, it was like the holy grail to me in the 80s and 90s. I was green with envy whenever I saw Amiga screenshots in game magazines. I had to learn a little bit about the system, but I was very happy when I finally got WinUAE and Amiga in a box working. Lovely system, a pity CBM let it fall behind the PC.

Rogue 17-10-2018 01:17 PM

Well, made me look into it, I remember reading about it. Here is Wiki, if we can trust it.

Quote:

OS support

IBM Disk Operating System version 1.1 by Microsoft
Which operating system IBM customers would choose was at first unclear.[81][23] Although the company expected that most would use PC DOS[48] IBM supported using CP/M-86—which became available six months after DOS[143]—or UCSD p-System as operating systems.[60] IBM promised that it would not favor one operating system over the others; the CP/M-86 support surprised Gates, who claimed that IBM was "blackmailed into it".[81] IBM was correct, nonetheless, in its expectation; one survey found that 96.3% of PCs were ordered with the $40 DOS compared to 3.4% for the $240 CP/M-86.[144]

The IBM PC's ROM BASIC and BIOS supported cassette tape storage. PC DOS itself did not support cassette tape storage. PC DOS version 1.00 supported only 160 kB SSDD floppies, but version 1.1, which was released nine months after the PC's introduction, supported 160 kB SSDD and 320 kB DSDD floppies. Support for the slightly larger nine sector per track 180 kB and 360 kB formats arrived 10 months later in March 1983.

https://en.wikipedia.org/wiki/IBM_Pe...ter#OS_support
FS-UAE is much easier for people who never used Amiga before, but glad you figured out WinUAE. For me, ClassicWB is much better choice for OS (you still need WB 3.0 or 3.1 to install it). ClassicWB comes in couple different versions, I use Full on Amiga, but P96 is far better choice for emulation.

http://classicwb.abime.net/

Sorry, didn't want to get this far off main topic here.

I like what you doing here, please continue. :) Are XT and AT next? :)

Neville 17-10-2018 01:26 PM

Quote:

Originally Posted by Rogue (Post 482928)

FS-UAE is much easier for people who never used Amiga before, but glad you figured out WinUAE. For me, ClassicWB is much better choice for OS (you still need WB 3.0 or 3.1 to install it). ClassicWB comes in couple different versions, I use Full on Amiga, but P96 is far better choice for emulation.

http://classicwb.abime.net/

Sorry, didn't want to get this far off main topic here.

I like what you doing here, please continue. :) Are XT and AT next? :)

Yes, packages like ClassicWB are great. I re-tried Amiga in a box a while ago, couldn't even complete the install process... it was build for UAE v8.0.8!!

All I needed to "get" Amiga emulation is that higher Kickstart doesn't mean higher compatibility and a few other notions about the system.

As for doing more PC machines, I don't know, really. I'd like to, but I don't feel much affinity to machines I haven't heard of / tried in real life. We'll see.

Neville 17-10-2018 02:34 PM

OK, for my next trick you're going to need a high-end PC... does anyone remember "The System 16 Arcade Emulator"? It was one of the first arcade emulators I ever used, together with Callus and DOS versions of MAME.

https://i.imgur.com/mH44XsV.png

I requires a P133 CPU, an S3 Virge (it crashes with lesser videocards, don't know why) and to set your PCem window as "resizable".

As for what it does, it emulates certain SEGA arcade titles, such as "E.SWAT", "Shinobi" or "Golden Axe". Back in the days, it didn't get any much cooler than this. Personally, I never could get enough of "Out Run".

https://i.imgur.com/oZVbjO9.png

This should also run under DOSBox, but the last time I tried it ran way too fast. My guess is that it relies on VSYNC to calculate the right speed on faster systems.

Rogue 17-10-2018 02:54 PM

LOL,

WinUAE 0.8.8 should work fine on pcem. :smile2::smile2:

Wonder if you guys know about LaunchBox, emulation front end. At some point its creator was bored and created DOS version of front end.

It works really great on DOS computer...

https://forums.launchbox-app.com/fil...ecial-edition/

Neville 17-10-2018 04:17 PM

Quote:

Originally Posted by Rogue (Post 482933)
LOL,

WinUAE 0.8.8 should work fine on pcem. :smile2::smile2:

I wouldn't bother. Its compatibility (even for a plain A500) is way below today's WinUAE.

Quote:

Originally Posted by Rogue (Post 482933)
Wonder if you guys know about LaunchBox, emulation front end. At some point its creator was bored and created DOS version of front end.

It works really great on DOS computer...

https://forums.launchbox-app.com/fil...ecial-edition/

I know about Launchbox, but I didn't know about the DOS version. Looks like something work trying. I didn't use a shell like application back in the day, but I've found out even a half-decent one like DOSSHELL can come in handy.

EDIT: It's pretty decent and lightweight. The main disadvantage is that it won't let you run files from your harddrive directly, as other shells do, instead you need to create a profile for every program you want to run. Still quite good.

https://i.imgur.com/cmdVbRE.png

For my emulated DOS machines I prefer a free Norton Commander clone called UFO: Universal File Operator.

Rogue 18-10-2018 01:05 PM

Quote:

Originally Posted by Neville (Post 482934)
For my emulated DOS machines I prefer a free Norton Commander clone called UFO: Universal File Operator.

LOL,

Even on Win10 machines I use Multi Commander and I still have license for Total Commander (Use it since my Amiga days)

Zip bunch of folders, rename and change extension all at once - very easy with this helpful tools. :)

http://multicommander.com/

https://www.ghisler.com/

Total commander for windows works well on Win95 computer if you need to work with files.

Check 5th screen on this topic...

http://eab.abime.net/showthread.php?t=94690

Neville 18-10-2018 01:14 PM

Yes, some of those tasks are hampered by Windows poor interface and even poorer file explorer. I often need to use other programs such as Fast File Renamer to gets things done. I would entirely replace the explorer, but to be honest I don't like the interface of the usual replacements.

Rogue 18-10-2018 01:27 PM

I think I am more prone still to use them because they remind me of Dir(ectory)Opus on Amiga.

http://i.imgur.com/RSHzKK8.png

On DOS Norton Commander was tool of choice.

As for DOS version of LaunchBox, I wonder if Jason will add other emulator support, turning it into great tool for emulation on my old PC, that is currently boxed in garage due to pcem and other emulators. With last move I got rid of Pentium 100, but still have bunch of old laptops, 2 x P2 - 450Mhz end bunch of newer computers.

Neville 18-10-2018 01:33 PM

Yes, a lot of those Windows Explorer clones retain the double screen interface of Norton Commander or DOPUS. I can easily see how nostalgia plays a part in that.

I don't personally keep old hardware around... I was happy to get rid of my old Amstrad CPC, my Game Boy and my previous PCs. There's something cool about being able to run everything from my harddrive, even with emulation glitches and all. I do understand the people who prefer the real thing, though. Nothing wrong with a garage full of working old machines.

Scatty 19-10-2018 10:25 AM

Sometimes you'd be happy to keep the old real thing ones, like for example you'll most certainly have some troubles running Knights of the Old Republic I on a Windows 10 machine, and most certainly won't get to run KotOR II at all.
Makes me happy I still have my old single-core Dell XPS M170 laptop, one of the last powerful gaming single-cores from back in the day which could run Doom III without a hitch. With Windows XP, both those games above run like a charm. Same goes for Baldur's Gate / Baldur's Gate II ToB. Overall Windows 10 stinks, but what can you do, time goes on...

Rogue 19-02-2019 01:10 PM

Back to OP post - were you able to setup hard disk for Tandy 1000? What do you select for sound, as there is no Tandy sound option for sound card?!

From what I know, there were 10-20 MB original HD sold with it, and later bit larger.

Neville 19-02-2019 01:23 PM

I set up a 20 Mb. harddrive. It may or may not have worked on a real machine, but PCem has something called PcemHD, a virtual controller that helps with older computer models and harddrives.

As for the sound, I left both entries blank. PCem does emulate the tree channel speaker from the PCjr. / Tandy 1000 computers IIRC. I'm not so sure about the Tandy DAC of later models.


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