8-Bit Operating Systems

This was originally printed in the last issue of Link Magazine, and is reprinted here, with updates, by the author. I finally got off my duff and incorporated all the mail people have been sending me. A few more changes are yet to be made; keep that mail coming.

Please do note that, as my consciousness of computer history expands, the title is becoming increasingly inaccurate. For example, I mention nothing of mainframe or minicomputer OSes (mostly due to ignorance) and so I should probably call this "Home Computer Operating Systems Through Time" even though not all of these OSes are purely home computer machines, particularly CP/M. The title is left for historical reasons, though.

New changes were last made August 2001. If you have more information about these computer systems, or have info on other systems not mentioned, please mail the maintainer.

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by Cameron Kaiser

Contrary to popular belief, God did not create the operating system
in six days. If He had, it would have been much better than the
ones we have now. Nonetheless, we got 'em, so we'd better learn 'em.
While some operating systems, like the love-hate Unix, have been
around since the early days of digital computing (read 1960's),
most have appeared in the late 70's to the present time, varying
from powerful multiuser OS's to little OS's that ran on 8 bit
computers in under 64K of memory. This is just the briefest portion
of operating systems, from then until now.

To establish a point of reference, all computers must have an OS.
The OS controls input and output; makes reasonable (questionable in
some) effort to control peripherals; and in short acts as the
interface between you the user, the software, and the hardware.
Early on, OSes were individualized. Since computers were a rarity,
the question of standardization was ignored, since there were so
few computers to be standardized, and consequently the OSes were
tied to the capabilities and purposes of each system. Not until the
age of microcomputers, somewhere near the late 70's, do we begin to
see any coherent pattern in the chaos. This is where our story
begins, with:


The first primary microcomputers on the block were the Commodore
PET, the Tandy, and the Apple II. (There IS in fact an Apple I, but
only 200 of them were ever manufactured. One of them hangs in
Apple's offices with the label "Our Founder".) Perhaps it would be
a good idea to look at how these respective companies fared in the
OS world.
	Tandy is one of the great could-have-beens in the computer
world. Their electronics chain, Radio Shack, is known worldwide.
Their appliance clones and lines make huge profits. Yet Tandy never
managed to crack the microcomputer world to any great degree because
their machines were so badly underpowered. Tandy's first foray was
the TRS-80 in its various incarnations. The TRS, when first
introduced, was a hot seller because of (at that time) its powerful
operating system and the increasing number of software applications
for it. Where the TRS-80 fell flat was failing to keep state of the
art: many new computers introduced enhanced video, or easier to use
operating systems; the TRS kept its 80-column b&w (and damn hard to
Correction: The original TRS-80 Model I had a 64x16 screen, though the Model II apparently did have the 80 column one. Thanks to Ricardo Banffy for the correction.

Also, I should have been a little more circumspect when I said "underpowered" -- certainly when the TRS-80s first emerged, when their major competition was the Commodore PET and Apple I/II, they were most certainly not. Tandy's biggest problem was that they actively discouraged any third-party support for their machines, with little room for expandability and no assistance for developers. Commodore itself wasn't much better. People started gravitating towards the more hacker-friendly Apple computers about this time. Commodore realised its mistake, but Tandy, tellingly, did not. In fact, while many authorities will cite the early spreadsheet VisiCalc as the killer application for the Apple II, it was originally developed on the TRS-80. Presumably Tandy's developer-unfriendly stance made the developers start porting it, and it was on the Apple II that it started to take hold (later CP/M and MS-DOS). Thanks to Alex Censor.

Neat Fact: Peter Norton's famous utilities collection, which is now sold by Symantec, was originally written for the TRS-80. Only later was it ported to DOS. (Alex encore.)

read) screen and its cryptic TRS-DOS, which rapidly gained the
moniker Trash-DOS. Tandy's next attempt was the CoCo line, going
through the CoCo 1 to the CoCo 3. The CoCo 3 actually was a fairly
good computer, with 128K, reasonable graphics and sound, complete
downward compatibility with others in its line and fair support
with Tandy. However, the CoCo was rapidly eclipsed by its primary
competition, the Commodore 64 (which we'll see later) and when
Tandy dropped it the CoCo faded away. Tandy now spends its time
making underpowered PC clones.
Update: Tandy no longer makes PCs, having now entered a licensing agreement with IBM to sell their Aptiva line. That seems to have folded too, though, because now I see Compaqs in my local shop. The Tandy PCs had somewhat of a different problem than the TRS-80s; by trying to top IBM's systems in features, they only succeeded in making them incompatible. (Thanks to Alex Censor.)

The venerable CoCos are now officially unsupported, as near as I can determine. Color Computers were powered by the many variants of the famous Motorola 6809 and the 6847 video chip (except the CoCo 3 which used the ACVC(?) and the 68B09E), and ranged in memory sizes up to 128KB. The Dragon series of computers, made by Belgian concern Dragon Data, were at least partially compatible with the CoCos -- BASIC programs could run, but for legal reasons memory mappings were different and so most of the games, which used ML, didn't. Apparently, the CoCos could be networked together. I myself used to assist a teacher who used a CoCo 3 as a fileserver and through cassette interfaces distributed programs to CoCo 2 clients in the classroom -- pretty neat, even in 1988. Many CoCos today run OS-9 -- see Multi-Platform operating systems.

Tandy also rebadged computers for sale through their stores (and, for that matter, still rebadge just about everything else, including Casio keyboards and various audio components). Most noteworthy was the Model 100, a rebadged Kyocera machine with a small LCD screen, built-in BASIC, a built-in word processor, and a built-in term program for the internal 300 baud modem. The later 102 and 200 models followed. NEC also had similar machines, notably the 8201A and 8300, which were largely BASIC compatible but had different memory layouts. I might also mention the Tandy Pocket Computers; these heterogeneous devices were rebadged Casio and Sharp devices and resemble oversized calculators, but in fact were complete computers, could save and load from tape, and some could even print to tiny plotters and dot-matrix printers. My PC-4 weighs in at a flyweight 1.5K, even with RAM expansion, but the beefy PC-2 could accomodate much more RAM and had a very complete BASIC.

Neat Fact: The POKE command on CoCos makes the processor heat up. Didn't Tandy know what a heat sink was?

	The Apple II series, until officially discontinued, was one
of the bigger success stories in the 8-bit market. Used all over in
American school systems, and frequent in American households, the
Apple II, going from the plain-vanilla version to the popular Apple
IIe/c, was a staple in its class. The Apple has several OS's: Integer
BASIC, which was a throwback to the old 48K Apple II; DOS 3.3,
which was the most common of the DOSes used on the Apple; and the
sophisticated but irksome ProDOS, which was Apple's last shot.
Apple had the strength of a huge number of users and its massive
software library, which encompassed cheesy games to powerful
applications like AppleWorks, but the weaknesses of poor graphics,
dumb peripherals (meaning they did not manage themselves, but had
to depend on the host computer, a very poor arrangement), no sound
above beeps at various frequencies, and above all a nasty price
A raft of add-on boards (like the Mockingboard for sound) could correct these deficiencies, but there wasn't much software for them.
tag. Apple made an attempt at recapturing the market with the
beautiful but impractical Apple IIgs, which had some takers in the
school systems, but with the advent of the Macintosh Apple phased
out the II line. An Apple III was also manufactured, but it was not
compatible with its more successful progenitors and was a miserable
failure. The Apple II series also inspired a number of clones: the
Franklin Ace and the Laser 128 series, which incorporated a number
of useful gadgets, like mice, numeric keypads, etc. that Apple
normally bled people for. After these became increasingly popular,
Apple eventually sued them but it was not a big deal since Laser
went to making PC clones and Franklin to its line of pocket
dictionaries and encyclopedias.
Clarification: You can read ProDOS volumes on a Mac, so this is at least one use for ProDOS. Apple still has FTP support for some 8-bits (mostly the IIgs) at their FTP repository.

Several alternative operating systems exist, besides Quark Catalyst and GEOS. I have now been made aware of GNO/ME, which does best on the IIgs, and apparently an OS9 post exists, but I cannot confirm this.

Apple did not lose any sleep over the graphics or sound capabilities of the 8-bits. But, as was mentioned, third-party manufacturers made a bevy of them. Most of today's development continues for the IIgs, which has a considerably more multimedia-friendly architecture (up to 4096 colours, which compared favourably with the popular Amigas of that time). The IIgs doesn't belong in this listing really because it's actually a 16 bit system based around the 65C816 (the big brother to the MOS 6500 series of processors that power the 8-bit Apple IIs, the Commodore 8-bit series and the Atari 8-bit series), but it has a built-in Apple II compatibility mode which the corresponding computers (Atari ST and Amiga) do not. Interestingly, the Commodore 64 can now be powered by the 65C816 with an add-on cartridge called the SuperCPU.

Applesoft BASIC was widely regarded as one of the saner implementations of BASIC (but not Integer BASIC, which was irksome). In fact, it was copied practically identically in the Coleco ADAM.

Update: Steve Jobs is back. After having started the company in his garage with Steve Wozniak (the 'Woz' on early IIgs models is his zany signature), Jobs was forced out by then-executive John Sculley over a power struggle in 1985, right as the Macintosh was trying to crack the market. Apple then fell on hard times as their market share dwindled.

Jobs had not been idle, as he introduced his Unix workstation, the NeXT, in the interim. NeXT machines run a unique Unix like operating system which has made them popular in universities (and popular with 3-D games giant id Software, which used them to develop Wolfenstein 3D and Doom). Apple bought NeXT as an attempt to shore up their operating system development, bringing Jobs back into the corporate board. When then-CEO Gil Amelio was forced out in 1997, Jobs became acting CEO.

Apple has since survived the Mac world's disapproval over a (so far :-) benign influx of capital and development promises from Microsoft, as well as the constant predictions of the company's immiment demise. Their recent releases, the G4 series of computers, are aiming for high end markets, which is probably wise granted that the largest complaint about Apple systems is their price, and reportedly they have exceeded their expected demand by almost 50% since their introduction. The iMac, their "all in a box" computer, has skyrocketed in sales, becoming one of the most popular computers of its year of introduction, and one that even has formerly hardened PC users defecting. Apple is now posting profits, and their innovator image has come back with a new and surprising facet: affordability. Whoda thunk it?

Moreover, with the successful launch of OS X, which has Macintosh owners including myself drooling over the prospect of a true, hardcore, open source BSD Unix kernel wrapped in a sweet GUI like Aqua, Apple has finally demonstrated they're willing to bring power to the people combined with adherence to standards at a good price best of all. OS X dodges the stability and multitasking flaws that plagued earlier versions of MacOS, and also is the first Unix in my opinion to successfully translate the power of a high-performance network operating system onto a home desktop and hide the depths of Unix away from novice users who think they're just using a really cool-looking computer, yet still let a power freak like myself at /bin/tcsh if I want my CLI. Eat that, Windows XP. The DVD and CD-burning issues should be corrected, if not already, very soon now.

Neat Fact: The operating system for the Apple III was called SOS. Given the computer's miserable failure in the market, it looks like the name was appropriate.

Neat Fact: A hardware add-on for the Commodore 64 called the Spartan Mimic could make the 64 into a fully functional Apple II. As the two systems are largely dissimilar -- even down to the CPU level, as 64s are powered by a 6502 variant called the 6510, while Apple IIs use the various classic 6502 varieties (the NMOS 6502 and the 65C02) -- the box, which occupied all the ports on the 64, was essentially an Apple II in a case without keyboard or monitor, and cost as much as you would expect (i.e., a lot). The idea was neat, but the cost was horrific. Moreover, 64 peripherals, since they are "smart" devices (see below), needed modification to work with it, making the total system cost even pricier. Consequently, the device fared badly, and is virtually forgotten. If anyone has one of these boxes, please let me know.

Neat Fact: Apple Computer began life with a very, very big trademark dispute with, of all people, the Beatles. Beatles records are distributed by music conglomerate EMI (on their Parlophone line), but the Beatles mark is actually called Apple Records. Apparently, Apple Records was guaranteed by Apple Computer that they would never go into the music business, so Apple Records dropped their trademark infringement suit. But when Apple Computer brought its CD-ROM drives out for the Macintosh, Apple Records brought back the lawsuit (perceiving the CD-ROMs as evidence of existence in the music market, supposedly). Presumably it has been settled.

Apple has some more history links on their very own Apple History page. In fact, they linked this one. :-)

	However, these two behemoths pale in comparison to what
for a time was the big boy on the block: Commodore Business
Machines. When Commodore first introduced the PET, it was fairly
popular, but not as much as when it went into its color 8-bit
line, with the VIC-20, the 64 (which even as late as 1991 was still
selling at the rate of 6-7 million units worldwide), and the 64's
bigger brother, the 128. The contemporary Commodore OS (read: 64)
was based around its version of BASIC. All commands to peripherals,
which were "smart" (having their own memory, processor and
handlers), were done through BASIC; the computer started up in
BASIC; and BASIC was built into ROM. The Commodore 64 wowed the world
as a wonderbox when it first arrived in 1982, with the then
extraordinary 16-color graphics, 3-voice sound, and bankable memory
based around the efficient MOS 6500 series (specifically, the 6510).
(Believe it or not, a 16-bit variant of the 6510, the 65816,
powers the Super Nintendo.) Since the BASIC did not have the custom
commands to manipulate many of the advanced features the 64 had, a
number of add-ons appeared: fastloaders to improve (sometimes to
massive ratios) the speed of the miserable 1541 disk drives;
BASIC extensions of all sorts, from the pitiful Simon's Basic to
bigger development systems like Epyx Programmer's Toolkit; and
hardware enhancements, such as RAM expansions, high-speed RS232
boxes and interfaces to non-Commodore printers. Another key was the
GEOS operating system, made by Berkeley Softworks (now GeoWorks).
Although it was slow, clunky, crash-prone and belligerent, it has
developed a loyal following because it presents a powerful
80-column Mac-like GUI on the 64. Huge amounts of software exist
for it, from games to powerful business programs. The 64 can even
GEOS gets its own entry under Multi-Platform at the end; read on.
behave like a PC or Unix box: programs like CS-DOS and the powerful A64/OS
and LUnix operating systems convert the 64 into smaller versions of their
LUnix continues to be developed, now boasting TCP/IP abilities and a true PPP client. Visit its home page and download it.
bigger competitors. The 64, while officially put to rest somewhere
back in the early 1990's, finally and abruptly got the boot when
CBM declared bankruptcy last year, but millions are still in use.
"Last year" is 1994, although it may have actually been a bit earlier.
The Commodore 128, its bigger and better cousin, did everything the
64 did, including CP/M (discussed later), 80 column video, its own
The 128 probably sold as well as it did because it was 64 compatible.
version of GEOS, and had all the BASIC commands necessary to take
advantage of its capabilities. While not as big a seller as the 64,
it has developed a big following in its own right. Commodore's
other 8-bits, including the Plus/4 and the 16, were disasters
because they were not compatible with the 64, and thus never hit
the market with any great interest. Commodore also developed the
Amiga series.
Update: After Commodore's demise, the company (mostly the Amiga) was bought by Escom GmBH. Escom itself folded, and amidst an abortive attempt to buy the Amiga trademark by American company VisCorp, the Amiga line was bought by Gateway, the PC clone manufacturer. After the typical corporate dillydallying and very little actual tangible product, the license was in turn granted in January 2000 to a new Amiga Corporation (the former Amino Development), and they are, yet again, working on another Amiga. Time will tell.

As for the prior Amigas, version 3.5 has since emerged. It is the last version of AmigaOS to support the 68K microprocessor; 3.9 has also been released, but it requires a PowerPC upgrade.

The Commodore 64, on the other hand, is also in Gateway's bag of stuff they got from the Amiga acquistion. But the Commodore name is actually owned by Tulip Computers BV (there's a web site). Commodore Computers BV, the resurrected company, sells PC clones, but no one has really done anything about the 64 itself. Unfortunate, as the next generation of Commodore peripherals is appearing, including an expansion card that upgrades the 64 and the 128 each to 20 MHz and up to 16 MB addressable. Hard drives up to several GB in size have been available for some time as well, so maybe the time is ripe for the comeback of a new, tougher 64. Creative Micro Designs, the company responsible for much of these add-ons, has become a big name in the remaining Commodore scene for their continued hardware support.

However, be sure you don't confuse the real 64 with a pretender. The Web.it Commodore 64 carries the Commodore logo and the 64 badge. Inside, it is actually a low-end 486 with ROM-based software and a specialised version of the CCS64 emulator. It doesn't use any of the Commodore peripherals, and to get it to read Commodore disks requires the X1541 cable and a Commodore disk drive. For that reason, the grizzled hackers like myself who have stuck with the old unit regard it as nothing more than an overpriced WebTV with a word processor, but to be fair it shows the amount of respect the C64 has engendered and also may introduce new people to this classic platform. Unfortunately, it has failed to sell anywhere near expected levels and the company is now apparently nowhere to be found.

More Information: Jack Tramiel, the original founder of Commodore Business Machines (back when they made typewriters and calculators), defected to Atari shortly after Commodore entered its 'salad days' period and bought them from Warner Communications during the great mid-1980s video game crash. Predictably, Commodore started taking its nosedive soon after the 128 peaked. Atari, however, did not benefit from Tramiel's success at Commodore, and it too could not fight the onslaught of IBM and Microsoft. Tramiel's name was never associated with a business success story again.

See the Atari entry for what happened to Jack's business acumen after.

When comparing absolute brand names (not OSes, like Wintel), the Commodore 64 is still the best selling single platform in the world. No other single computer model comes close.

Neat Fact: Most authorities agreed -- the Commodore 64 had probably the worst BASIC dialect ever to grace an 8-bit. In actuality, the 64 really has a very simple, unspectacular implementation with no special support for the 64's then-extraordinary graphics and sound hardware (compare with Applesoft and Atari BASIC, which had such commands from the get-go). Commodore realised this deficiency very quickly and introduced add-ons such as Simon's BASIC for the gap; future models of Commodores, including the 16, the +4, the 128, and the Amigas, would all have enhanced BASICs designed to show off Commodore's multimedia supremacy.

Neat Fact: Microsoft wrote the original BASIC for the Commodore PETs, but this was back in the day when Bill Gates hadn't as much money and the struggling company agreed to offer Commodore a one-time license to use the BASIC in their computers. Boy, betcha Bill Gates kicks himself now, after all the copies of a later version of the code appeared in those millions of C64s. To be sure, Commodore significantly rewrote the BASIC for the VIC-20, and that version became the basis of the BASIC in the 64, 128, Plus/4 and others. But turn on a 128, and what do you see? (C)1977 MICROSOFT. Despite this nod to the OS's history, Gates never got a penny. Cry for him, won't you?

Neat Fact: It is widely believed to be a myth that the 64 was responsible for the rise of America Online. Surprise: it's the truth. The original online service AOL came from was a 64-exclusive networked BBS system called QuantumLink, which was a merger of Steve Case's QuantumLink (ring any bells? Steve Case? Mmmm, Steve Case?) and a early online gaming service called PlayNet. QuantumLink did in fact continue until the early days of America Online, but was abruptly cancelled to the frank irritation of the 64 users on it (consequently, Steve Case is regarded as somewhat less than cow dung in most hardcore 64 groups). Proof? Most of the old PlayNet architecture was never modified. Ever wonder why you are restricted to a 10 character name? That was a PlayNet decision so that they could fit four names to a Commodore 64 40-column line. It has never been changed since.

Neat Fact: The most well-known brother to the Commodore 64 is the Commodore 128, a minor hit in its own right (I have a 128DCR, one of the models with an integrated disk drive). There is, in fact, a Commodore 65, a mythical model developed in Commodore's RandD labs with Amiga-quality graphics, a C64 compatibility mode, and a built-in 3.5" disk drive. When Commodore was liquidated in '94, some of these prototypes escaped and were sold off to warehouses (several hundred or so, from complete systems to motherboards). You can get more information on them from here.

Neat Fact: Most movies show the very unrealistic scenario of some computer program that can cause actual physical hardware damage to chip components. (Forcing HD crashes isn't that hard. ;-) This is just about impossible to do in real life -- except in later model Commodore PETs, where a single POKE (memory store) to a video chip location can fry the entire video subsystem. Older PETs allowed you to run the system at a higher refresh rate and get a free speed boost. When Commodore fixed this anomaly, the POKE would still run the higher refresh rate which the video controller could no longer cope with. Hence, warped screens, and after a couple of minutes, no screen at all -- even if you turned it off and back on, the damage is permanent. Yikes!

	Other 8-bit systems of note:
	Texas Instruments' TI/99 series were another of the big
should-have-been-but-wasn'ts. Burdened by total incompatibility
with anything else, suffering terrible graphics and sound, and a
non-standard BASIC, the TI/99's developed a small following that
Correction: Actually, the TI 99/4's had more than adequate graphics output. However, the 4 series was designed by TI's Consumer Products division, and therefore crippled down for the home market. None of its special features were accessible to the casual programmer. Extended BASIC addressed some of these shortcomings, and even supported sprites, but TI's lack of good support and the Commodore 64 were the knockout punch. Thanks to Tom Wills' TI mailing list for this information.

Update: There is a more advanced variant of the TI 99 series called the Geneve, manufactured by Myarc. The Geneve is largely, but not wholly, compatible with its progenitor. (Full name, the Myarc 9640.)

More Information: One of the most baffling things about the TI is that its CPU, the TMS 9900, is in fact a 16 bit processor, and it deals in 16-bit quantities internally; but, it only exposes eight lines to the system, and multiplexes them instead for the full 16 bits.

The Tomy Tutor is in fact a TI "clone" -- it too is based on the 9900 (actually a faster variant, the 9995), but Tomy played the 16-bit angle up to ridiculous proportions, using this as their marketing ploy in the increasingly then-glutted 8-bit market. (As a note, the 9995 also has a multiplexed bus, but this is built into the chip, not handled externally as in the 99/4A.) In fact, the TI chip set powered several computers -- 9918 variants apparently powered the Tutor and the ADAM, as well as an obscure system called the Sord.

Here's the only comprehensive Tomy Tutor site (if I may say so myself, since I wrote it).

was quickly alienated when TI hastily cut their losses and dropped
the line. TI now makes calculators, which it used to do and should
have stuck with, and also a very good line of laptops, leaving a
discouraged following behind.
Neat Fact: TI BASIC is double-interpreted. Not only is your program interpreted by the TI BASIC interpreter, but the interpreter is itself interpreted, written in a special language called GPL (Graphics Programming Language)! Thus, TI BASIC is dog slow compared with other classic micros. The Tomy, on the other hand, has an interpreter fully written in 9995 machine language, so it blows away its progenitor. I suspect that the Tomy graphics language GBASIC is really GPL in disguise, however, so GPL lives!
	Another computer that might have hit it big was the
Sinclair, a fairly well endowed system that would have hit it big
in Europe were it not for the spectre of the Commodore 64, which in
fact doomed many potential competitors in Europe during the early
1980's. The Sinclair's reasonable graphics capabilities and
friendlier style of usage were eventually eclipsed by CBM UK, along
with the BBC's Acorn, which should never have got out the door.
Clarification: The Sinclair was sold in the States by Timex, but Timex didn't want to challenge the 64 on its home turf. Thus, the Sinclair is really only well-known in the UK. The US models were the 1000, 1500 and 2068; the 1500 and 1000 were more or less direct clones of the ZX-81 (see below; the latter with built-in RAM expansion), but the 2068 was its own beast and only marginally compatible with the UK Spectrums, its closest relative. A converter cartridge was required to allow the 2068 to use Sinclair software, and this incompatibility was the 2068's Achilles heel.

More Information: Well-endowed is as well-endowed does; I oversimplified grossly. There is a massive line of Spectrums, from the ZX-80 to the QL and the top-of-the-line Spectrums. At the low end are the ZX-80 and ZX-81, with no graphics capabilities of any sort, fully B/W, and a whopping 1KB (!) of memory. The ZX-80 is very rare, but the ZX-81 was a smash hit in Britain, and was released in the States as the Timex Sinclair 1000. You could not type BASIC keywords in by hand, as it appears -- the keywords were on its horrid membrane keyboard, and you had to type them in with key combinations instead. Well, I think it's horrid on my TS1000, but Sinclair owners have been lecturing me that it was really very functional. Whatever. :-P

Neat Fact: The ZX-80 series were terribly slow, despite a 3.25MHz Z80 CPU. To reduce chip count, the designers made the Z80 handle everything, including keyboard and, tellingly, display. When the ZX-81 emerged, the developers allowed the screen update to be turned off and called this FAST mode. (Another important advancement was floating point, which was not in the ZX-80 BASIC either.) Thanks to Rich Dunn.

The ZX BASIC interpreter was a marvel of programming in that it worked with programs crammed into the 1KB of RAM so well -- there was even a MicroChess implementation (as was there for the old MOS KIM-1). Nevertheless, the 16KB RAM expansion was the most popular peripheral.

The colour Spectrums started at 16KB of RAM and maintained the maddening BASIC keyword combination quirk of the ZX-80s. Spectrums had reasonable resolution but a bizarre colour clash quirk that became the classic hallmark of Spectrum games. In spite of its horrid I/O, the BASIC quirks, the nutty graphics and the non-existent sound, the Spectrum enjoyed popularity in the UK almost on par with the Commodore 64, much to Jack Tramiel's chagrin and Clive Sinclair's glee. In the US, Timex tried to get that same popularity by releasing the Spectrums as the Timex Sinclair 2068. Unfortunately, because of the 2068's compatibility problems and the 64's established supremacy in the US, the 2068 never achieved its potential. Most Sinclair support, thus, is limited to Europe. Later Spectrum models introduced enhanced sound, but the graphics became a byword in the Sinclair community.

Neat Fact: The Spectrum+3 was noteworthy for finally allowing the user to type BASIC keywords out in full, but this was because the keywords were now no longer printed on the keyboard. A compatibility option offered users the ability to continue using key combinations for BASIC keywords, but since the keywords weren't printed anymore, users had to do them from memory!

Neat Fact: The Spectrum+ has a detachable keyboard. Literally. If you turn a unit upside down, all the keys will fall out.

The Sinclair QL doesn't really belong here, as it wasn't a Spectrum or ZX system (in fact, it's actually 16-bit, based on the Motorola 68008), but it is worth mentioning for its unique microcassette drives (with a pathetic 100K, mediocre in 1984 and terrible later) which though small were quite fast, and the QLAN networking system. QL was supposed to stand for 'Quantum Leap' but Sinclair's manufacturing tardiness branded it the 'Quite Late'. Its software was written by Psion. Apparently, its BASIC was quite good as well (presumably the key combinations were no longer needed).

Neat Fact: Sinclair picked up quite a lot of bad blood over the QL. Although introduced January 1984, the machine did not ship until May, but orders were still taken and checks cashed anyway -- at 399 UK pounds a pop! Worse, early models had a case too small to accomodate all the components, so a tacked-on portion hanging out the back of the unit covered the remainder.

Acorn is a company in its own right. Today they make the Archimedes, a wonderful computer that survives in the British education system.

More Information: There are several Acorn systems as well. The Acorn Atom was a kit computer based on the 6502, introduced 1981; the BBC series of computers were based on the 6502A and differed only in memory and enhanced graphics, similar to the Spectrum series, from the model A (16K, 320x256x2 or 160x256x4) to the B+ (64K and a new 640x256x2 mode), introduced 1981 and 1985 respectively. Today's Acorns are based primarily on the ARM processors, a RISC architecture with some similarities to the 6502.

	Not to be outdone, Atari was probably the first computer in
your home, although you might not have recognized it as such. When
Nolan Bushnell released his wildly popular Pong, this primitive
dedicated system wormed its way into the hearts and habits of happy
Americans. The 2600, 5200 and 7800 video game series made addicts
out of many a kid (including me). And, for a time, Atari did at
least as well as its competitors with its hundred line: the 400,
600, 800 and 1200 series computers. Carrying fair graphics, good
sound, a reasonably efficient DOS and a good number of
applications, the Ataris did well until their faults started
bubbling to the surface. By not adhering to the Microsoft BASIC
standard (e.g. Commodore 64, Apple II), Atari seriously shot
themselves in the foot, and its graphics and sound capabilities
were overshadowed by the 64's. In addition, Atari just could not
Clarification: People have been complaining that I don't give the Atari ANTIC graphics chip a fair shake against the Commodore 64's VIC-II. Here is my justification for the above statement.

While the ANTIC has many, many more colours than the VIC-II's sixteen colour palette, the ANTIC modes are extremely limited on how many you can have on screen at once. At the highest resolution possible on the ANTIC (320x192) which is still smaller than Commodore standard hi-res (320x200), you get two colours only (one hue with two luminances according to my technical documentation), while the Commodore can still display all sixteen. Possibly a fairer comparison is Commodore multicolour (160x200) versus GRAPHICS 15 (160x192) but the ANTIC can still only keep four colours on the screen. In fact, to get sixteen colours from ANTIC onscreen requires you drop all the way to GRAPHICS 11 and 80x192; while the VIC-II does have an 8x8 colour limitation (2 colours per 8x8 cell at 320x200, 4 colours per cell at 160x200 -- but all cell colours are largely independent except for the background in 160x200, so there are no palette registers per se), all sixteen colours available to it can still be displayed simultaneously on screen in any graphics mode the chip can generate. Furthermore, interlaced graphics modes are possible on the VIC-II that completely do away with that 8x8 cell restriction and expand the palette to over 128 colours with some added CPU work.

In addition, player/missile graphics, while certainly powerful, lack the flexibility of VIC-II sprites. There are only five players (vs. eight VIC-II sprites) and to get the missiles, you lose one player. Players can be 128 or 256 scanlines tall, which is definitely an improvement on the VIC-II (max size 21 scanlines or 42 in double-Y mode), but only eight wide (VIC: 24 pixels wide or 48 in double-X). The collision detection systems are roughly on par between the two systems, but Commodore sprites can also be hardware-resized (1x or 2x in X, Y or both), have flexible object priority (sprites can dynamically go behind or in front of the background independent of others), and can be either monochrome or be painted in three colours with a 2:1 reduction in horizontal resolution. And again, raster work is possible that can give you eight new sprites on every subsequent scan line -- potentially over 1600 in total, although they would be only one scan line tall, but 32-sprite effects are quite common and easy to manage with very little performance loss.

One thing that the ANTIC does do very well is its display list capability, later taken by designer Jay Miner to the Amiga. You can generate complicated displays this way that at least to some degree circumvent the resolution and colour limitations in a fairly straight-forward manner. However, a Commodore can do this with a raster IRQ using interrupts generated by the VIC-II and clever code. To be sure, this is somewhat more complicated and requires more CPU overhead, but the ANTIC has no monopoly on this ability.

With this all in mind, the VIC-II is by no means the winner by a mile, but I think it is the more powerful graphics chip feature vs. feature. The ANTIC is a very powerful chip as well -- make no mistake -- but the VIC-II does almost all of its features and with greater flexibility in general besides.

Now, please don't start any POKEY vs. C64 SID (sound) arguments either. SID really was untouched for years until the modern OPL synths started appearing at the consumer level, and even then the SID held its own. No sound chip of that contemporary day had the SID's ADSR envelope flexibility, output quality, range of effects and hack power (as an example, a well-known voltage leak was exploited as a 4-bit digital sound output).

None of this is meant to be an Atari slam -- I own two Atari 8-bits myself. Ataris have a faster clock speed than the Commodores, I like the convenience of a true MFM disk format, and Atari programmers have done ingenious things with their machines. But I think my conclusions are justified at least on this score.

crack the home market (Commodore's zone), nor the school market
(Apple's department). Its XL line (600XL, etc.) was also
problematic in that it was almost, but not quite, compatible with
its older brothers, requiring a Translator disk that did not quite
fix the problem for some programs. Atari released a XE line, which
was just a repackage of the 1200's, and its ST line, a 16 bit
Correction: The difference between the XL series and the straight hundred-series is the presence of built-in Atari BASIC. The XE series required the translator disk. Thanks to Ken Bond for the correction.

More Information: There are at least several alternative operating systems for the Atari that I have recently become aware of. A port(?) of Atari ST TOS (Tramiel Operating System, how egotistical ;-) existed (TOS was based on Digital Research's GEM, but I don't think the 8-bit version was), and there was also SpartaDOS, a UNIX like system that allowed external storage up to 10MB.

Factory standard Atari DOS was called, with all the creativity Atari marketing could muster, "Atari DOS" and had a simple keyboard driven menu. DOS 3.0 was considered a lemon because it didn't read 2.0 disks, so Atari, which was apparently under Tramiel control at the time, released Atari DOS 2.5 with the XE line (and this seems to explain the need for the translator disk). Some neat toys that Atari never released can be seen at www.atari.nu. Thanks to "SulfurFury" for this additional information.

When Atari was sold to Warner
Communications, it eventually faded away. However, its video game
division, Atari Games, is still out there sucking up your quarters.
Update: Atari Games, including the Tengen consumer division, has been bought by Williams Corporation as part of their video games enterprise, which includes what used to be Bally Midway, but this was not the fate of Atari itself.

According to the American government Securities and Exchange Commission, JTS Technologies, which owned the remainder of Atari after it folded (hint: JTS stands for Jack ...), sold their remaining interest to Hasbro, the American toy manufacturer, for $5 million on 23 February 1998. Hasbro created a new division of their Hasbro Interactive line for their new properties; the new subsidiary had the Atari name and carried the rights to the 2600 through 7800 consoles, the Lynx Jaguar, the Atari 800, the ST (and TOS), the 8-bit operating systems (thus Atari DOS) and the Portfolio palmtop. More significantly, most of the classic Atari games, including Centipede, Asteroids, Battlezone, Missile Command, Tempest and the venerable Pong, became service marks of Hasbro (apparently these were not sold to Williams with the rest of the video games division) and the new Hasbro-powered Atari wasted no time in licensing or converting many of them into new PC games. Check them out at your local software store, as many are still available. There still seems to be some issues on JTS's absorption of Atari's debt (apparently JTS took more than $50 million in debt absorbed from Atari) -- shareholders questioned the low sale price to Hasbro as evidence of skulduggery or a straight-out fire sale.

After several years in the software business, Hasbro decided they didn't like the market either and sold off Hasbro Interactive on 29 January 2001 for $100 million to French software concern Infogrames. The deal not only included all the old Atari service marks and games, but also legendary developer MicroProse and over 250 software titles. Infogrames also gained exclusive rights to develop software based on Hasbro properties as part of a long-term licensing arrangement. Infogrames has not announced what they intend to do with Atari, but it seems unlikely the hardware will be resurrected.

"Catch-All Department"

People have told me about computers I totally forgot. Since most of these ran their own proprietary operating systems, I'll put them here.

Coleco ADAM

Thanks to Gavin Gregor Young. The ADAM computer was the followup to Coleco's fairly successful ColecoVision machine -- in the true sense of the word, too, as apparently it came as both an upgrade to the ColecoVision and as a standalone machine, powered by a Z80A system that was CP/M-like (fairly probable given the processor), and a CP/M for it is known to exist -- there is even a WordStar version hacked for the 32-characters per row display! It used the infamous TMS9918A video chip, variants of which powered the Sord (!), the TI series and the elusive Tomy Tutor, and had 64K of RAM. ADAM was noteworthy for having a large amount of ROM, mostly for its built-in word processor (but you had to read in BASIC from disk or tape -- puzzle), the power supply built into the printer (in fact, ADAM didn't work without it, so it came with one :-), and two built-in digital cassette drives. These drives were also a source of some frustration as they could use regular audio cassettes, but you needed to get them formatted by Coleco first. However, they could hold a whopping 256KB on each cassette, and if you connected up floppies at 320KB a pop, you would have a gargantuan (in 1983) 832KB of mass storage. Not bad! More intriguing was that the ADAM's cassettes had probably the world's only random access tape system -- it had a directory placed strategically on the cassette in such a way that the drives could spin through to it and locate things at almost disk-drive speed, a novelty then and pretty neat now. ADAM's BASIC was based on (of all things) Applesoft BASIC, so if you typed 10 HOME on an ADAM, it would do what you expect when you RUN it.

Neat Fact: ADAM apparently generated a massive electromagnetic surge on start up. You won't go into warp yourself, but any data on the tapes inside your tape drives might.

ADAM was terribly unsuccessful, since it lost big to the rampaging 64. However, it enjoys a terrific amount of support (check out The ADAM Resource), and people have supposedly created IDE hard drives, 2MB RAM disks, 80-column cards, and additional printers for it. Even more startling was a note from Scott Gordon who told me about the 40MB (!) hard drives designed for the ADAM. Wow!

Ohio Scientific Challenger IP

Russ Adams tells me about this unusual 6502 based system from the late 1970s. Its operating system was BASIC, but had a built-in ML monitor and could generate a black-and-white TV display with its 4K of RAM (max 8K). In 1978, it was succeeded by the IIP.


All the previous systems were localized to one computer, and often
hardcoded into memory. Here are those operating systems that
managed to make the jump from single-system to multi-system.
	GEOS, which was previously mentioned in reference to the
Commodore 64, also had an incarnation for the Apple II, which was
done in by Quark Catalyst. Catalyst was sponsored by Apple itself,
which was probably the reason for Apple GEOS's demise, even though
Catalyst was even clunkier than GEOS was. GEOS was also released
for the MS-DOS line, since it would run on older systems scorned by
Windows, but PC-GEOS, as phenomenally powerful as it is, was
eventually run down into a footnote in the PC GUI wars.
Update: After stagnating in abandonware hell, PC-GEOS developer Berkeley Softworks (later GeoWorks) sold the core and applications to New Deal. Today's New Deal is everything the original PC-GEOS was, but now includes Internet applications and a sophisticated desktop. A free evaluation version is now available.

Do note that PC-GEOS is related to its 8-bit cousins in name only. Apple GEOS was actually supposed to be compatible with Commodore GEOS, but this was never realised.

Commodore GEOS survives today. It is still manufactured and sold by licensee Creative Micro Designs, and two new versions have appeared: Wheels and MegaPatch 3. Both of these are unofficial upgrades and require an older version of GEOS.

	The MSX standard was another multisystem standard that was
supposed to be the Japanese invasion during the mid 80's. Computers
like the Tomy Tutor (the what? well, I have one of them ;-), the
Yamaha XS, and a number of other systems adhering to this standard
were doomed by none other than the 64, which in a fit of marketing
expertise or dumb luck was selling at its peak when the MSX line
was introduced.
More Information: The MSX was a chipset standard based around the Z80 CPU, and all inherited similar music and graphics capabilities.

Paul te Bokkel writes that the ROM BIOS was also standardized between generations. The first three MSX generations (MSX, MSX2 and MSX2+) were all based around varying CPU speeds and RAM size with the MSX2 carrying 128K of RAM and 128K of video RAM, better video (I would guess the TMS 9958 by this time) and sound, and with help the Z80 could run as fast as 7MHz (stock speed 3.5). The MSX2+ was even faster. The original MSX had 32K BASIC ROM (written by Microsoft!), 32K RAM minimum (with 64K you could run CP/M or MSX-DOS) and 16K video RAM, presumably powered through a version of the TMS 9918.

The later Turbo-R doesn't really belong here as it had a 32-bit Zilog CPU and Paul notes that the series had pretty much died by this point in Europe.

Paul adds that they were in general cross-compatible with two major exceptions: Philips' MSX2 systems had a different memory layout from Sony systems, for one, and the Spectravideo, which was advertised as MSX compatible, wasn't fully such although many programs would still run on it. The SV was notable for including CP/M, not MSX-DOS.

Sharp, Mitsubishi and Panasonic were other MSX manufacturers.

MSX stands for MicroSoft eXtended.

Correction: The Tomy Tutor is not an MSX box. It is a TI-like architecture.

	OS9 was an operating system that was one of the few, if not
the only, multitasking, multithreading, and, if you're lucky,
multi-user operating systems extant for an 8-bit system. Running in
Correction: It is singlethreading only, although later versions might have fixed this (?). Someome with more info, please mail me.

some versions for 6809 based systems, like CoCos, where it has
attracted a fierce fan club, for 68000 systems like Atari STs, and
even for the Apple II, OS9's fault was being branded a CoCo system
only (which it was primarily) and attracting a bad rep. In
addition, applications were not cross compatible. OS9 nowadays runs
on almost all of the TRS-80 line that is still in use, and on the
occasional ST (mostly in Europe).
Actually, CoCos, not TRS-80s. An OS-9 clone is emerging called Nitros-9 which promises faster speeds and 99% compatibility.
	The big mama of the multi-platform 8-bit OSes was CP/M,
however, which nearly replaced MS-DOS as the default OS for the PC
were it not for an upstart software company from Redmond,
Washington that did a better PR job (guess who?). Developed by Gary
Kildall's Digital Research in the mid 1970's, CP/M was the first
standardized OS ever created for microcomputers. CP/M had a
standard set of commands, (eventually) a standardized DOS, and even
standardized system utilities from one implementation to another.
In its heyday, CP/M was supported by companies as diverse as
Kaypro, Cromemco
Correction: Well, no, not Cromemco; Cromemco's CDOS was only roughly based on CP/M. While CP/M's standard complement of twenty-seven I/O calls were supported by CDOS, Cromemco further extended it to the point where CDOS could run CP/M applications, but not vice versa. This was further complicated by the fact that programs written specifically for the 4MHz Z80 in the Cromemco would not run on earlier 8080s, even those that did not use the extra CDOS I/O calls, and, because of format-level incompatibilities, CDOS could read other CP/M disks only in single-sided, single-density mode. Thanks to Helmut Liftin, a former Cromemco engineer, who should know. By the way, someone is out there using the Cromemco name, but it has nothing to do with the original company.
and even Apples and Commodores, which could emulate it with an 
add-on in the 64 and Apple II and could be a full-on CP/M box on the 128.
Disks between these systems (with the exception of the 64 and Apple II) were
even cross-platform readable, and because CP/M ran on the 8088 and
Oops -- that's 8080.
Z-80 processor series, the software would run exactly the same on
all of the systems. CP/M even had versions for other processors,
including CP/M-86, and other computers, such as the Apple II. With
all this going for it, CP/M ought to have succeeded, but was beaten
to the punch when it annoyed IBM, who was looking for someone to
create the operating system for its new XT series, and gave the
contract to Microsoft instead. The rest is history. Digital
Research made an abortive attempt to return to the market with its
GEM graphical system (which DID make a big hit on the ST, however),
and now markets DR-DOS, a pleasant alternative to MS-DOS, albeit
Update: CP/M is now owned by Caldera. My most current information indicates that Digital Research as it was no longer exists. Charles Richmond points out that it is freely distributable for non-commercial use, but it is not PD or freeware.

Gary Kildall passed away, apparently in 1994. We'll miss him.

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