Tuesday, 17 August 2021

IBM Personal Computer Model 5150 (1981)

Introduced August 1981

Four years on from the launch of the holy trinity of the Apple II, Tandy TRS-80 and Commodore PET there was a rapidly growing (but fragmented) multi-million dollar market worldwide. Although rival micros tended to be incompatible, business systems showed a growing standardisation around the CP/M operating system and the S-100 expansion bus. Home machines had wildly different hardware and software, but tended to be based around either the MOS 6502 or Zilog Z80 CPUs.

IBM Model 5150 and 5152 printer
IBM Model 5150 and 5152 printer

But in August 1981 came a paradigm shift, thanks to IBM. IBM seemed an unlikely player in the microcomputer market, specialising in powerful but incredibly expensive mainframes and whose initial microcomputer systems were also blistering pricey. It took IBM at least five years to develop a product, which was much slower than the microcomputer market was moving. IBM seemed old-fashioned in a market that was mostly dominated by younger and more agile competitors.

IBM could sense the way the wind was blowing, however. Cheap but versatile micros were finding their way into IBM customer sites while at the same time the market for big iron computing was faltering. IBM wanted a slice of the micro market, while at the same time it was aware that its traditional business processes would not be able to compete.

In a moment of enlightenment, IBM took one look at its internal rulebook and tore it up. Their entrance into microcomputers would follow a completely different path. Dubbed “Project Chess” by IBM, the development work attracts many top-flight IBM engineers to work on this new computer in complete secrecy. The result was the IBM Model 5150 - best known as the IBM Personal Computer or simply the IBM PC.

Instead of basing the PC around an IBM CPU, an Intel 8088 was chosen – as seen in the IBM Datamaster which was being developed at the same time. The PC also took a variant of the Datamaster’s keyboard and expansion slots, but then developed features all of its own. Output was either crisp text via a Monochrome Display Adapter (MDA) card to an existing model of IBM monitor, or to an compatible colour monitor with a Colour Graphics Adapter (CGA) card.

Although the PC could run a version of CP/M, the primary operating system was PC-DOS which was sourced from Microsoft. Quite how this choice of OS was made is now the stuff of legends. Initially IBM approached Digital Research (DR), the makers of CP/M, to provide a software platform for the PC. Although CP/M was designed to run on the Z80, an Intel version had been developed as well. Legend says that the boss of DR – Gary Kildall – was out flying his private plane when IBM turned up at the office unannounced, although the truth probably that DR and IBM couldn’t agree on a licensing structure. IBM then approached Microsoft and asked them to provide an OS. Microsoft didn’t actually make operating systems – their main business was BASIC – but a nearby company called Seattle Computer Products had an OS called QDOS that would run on the 8088. Microsoft bought the rights to QDOS, renamed it MS-DOS and then licensed it to IBM as PC-DOS while retaining the rights to sell MS-DOS themselves.

IBM PC with neatly-labelled floppies
IBM PC with neatly-labelled floppies


Compared to PCs of even just a few years later, the model 5150 was pretty limited. The 8088 was a cheaper and more readily available version of the 16-bit 8086, but the 8088 only had an 8-bit external bus. RAM was theoretically expandable to 640Kb which was substantially more than the competition, but typical configurations topped out 256Kb. Although the 5150 supported twin floppies (up to 320Kb each) the only way to support a hard disk was to use the 5161 expansion box which wasn’t available at time of launch.

The 5150 did have a cassette interface, although almost all systems were bought with floppy drives. Typical configurations would include two serial ports and a parallel port, but eventually you could add a joystick, network card, more memory and other options. The 8-bit expansion card design was physically robust, and IBM published all the specification so that third-party vendors could make their own.

IBM had a rebadged Epson MX-80 printer available as the IBM model 5152, the most popular dot-matrix printer of the time. You could add any other parallel or serial-port printer as long as your software had the drivers for it.

The use of an open architecture (where IBM described in detail the workings of the machine) plus industry standard components made this a very flexible system. Because it was well-built and designed – albeit expensive – it became a popular business computer, although realistically it was priced too high for the home market. Third-party software and hardware followed, so within a year of launch the PC could do everything any other machine could do plus much more.

It was a huge sales success, outstripping IBM’s most optimistic projections several times over. High demand meant that most initial units were sold in the US only. Production of machines for Europe officially started in 1981 when IBM launched a plant in Scotland, but grey imports existed before that. This delay gave the opportunity for rivals such as the ACT Sirius 1 to gain a foothold.

The 5150 was the direct ancestor of almost all PCs in use today (apart from Apple’s Macintosh machines). The IBM PC XT added more expansion slots and hard disk support in 1983, the IBM PC AT came in 1984 and used a much more powerful Intel 80286 CPU. It did seem at the time that IBM was onto a winner, but it didn’t take long for other companies to build compatible machines using the same architecture.

The only proprietary part of the PC was the BIOS which had to be emulated, or in some cases just ripped off from IBM. The Columbia Data Products MPC 1600 was the first true clone of the PC, launched less than a year after the 5150. Better known was the Compaq Portable, launched in 1983, which was not only 100% compatible (and used a legal BIOS) but it was transportable too. Thousands of other companies followed suit, and within a few years IBM’s control of the market was slipping.

In 1987, IBM attempted to change the direction of the PC industry with the launch of the PS/2 range which was more tightly controlled by IBM. Clone makers needed a licence to make a PS/2-type machine which had a different hardware architecture, but few bothered and instead the bulk of the market remained with machines with a direct line back to the original 5150. IBM continued in the PC business until 2005 when it sold the unit to Lenovo.

Today the 5150 commands decent prices for collectors, commanding prices of several hundred pounds for a good one, although they are much rarer in Europe than the United States (and if importing one, you need to get a voltage regulator unless you want to blow up your power supply). Of course, you can buy a direct descendant of the original PC in any computer shop which might give you a less antique experience…

Image credits:
Science Museum Group - CC BY-NC-SA 4.0
Rama & Musée Bolo - CC BY-SA 2.0 FR



Thursday, 29 July 2021

IBM Selectric (1961) and IBM Datamaster (1981)

Introduced July 1961 and July 1981

Remember typewriters? You know, the obsolete technology that existed before the obsolete technology called word processors? Somewhere after people wrote stuff down by hand? No? Oh well, the IBM Selectric probably isn’t for you.

By 1961, typewriters were clunky, slow and inflexible… but businesses everywhere relied on them. IBM had a different vision of what a typewriter could be, and the Selectric was much more feature rich than most of the machines on the market at the time.

Early IBM Selectric Typewriter
Early IBM Selectric Typewriter

One obvious different was the print head – instead of having an individual arm with each letter laid out in a complex mechanical arrangement, the Selectric had a “golf ball” print head which would rotate to find the letter you wanted. On the Selectric, the head moved from left to right rather than the paper moving from right to left. Crucially, if the operator wanted to change the font they would just stop typing and swap in a different print head.

A quite complex electromechanical arrangement made all this work, and to get the best out of the Selectric required either experience or training. But it was faster, more reliable and more flexible than traditional devices and IBM took a large share of the business market.

New versions with more features followed, although the Selectric units were incompatible with each other. Some had correcting ribbons, wordprocessing features and even local storage. Variants of the Selectric could be used as computer printers. By the time the brand was retired in 1986, IBM had sold more than 13 million Selectric devices.

20 years further on, IBM found itself on the cusp of a larger revolution. Business computers had been getting smaller, more powerful and – crucially – cheaper, which was becoming a possible threat for IBM’s large computer business.

IBM wanted its own microcomputer and had started working on creating a unit based on an Intel processor, which was a major design break for IBM who had previously used their own PALM CPUs in their machines. The results of this unconventional effort by IBM is probably not the computer that first springs to mind – the IBM PC – but instead the IBM System/23 Datamaster.

IBM Datamaster
IBM Datamaster

The Datamaster used many of the same or similar elements that would be seen in the PC, including the Intel CPU, expansion bus and keyboard. Instead of the PC’s now-familiar modular design, the Datamaster was an all-in-one box (not dissimilar to the original Mac) designed to be set up by people with no technical experience. It was also IBM’s cheapest computer to date.

Unfortunately for the Datamaster, it had been stuck in development hell and took a very long time to come to market. As it was being readied for launch, the team behind it were also finalising the IBM PC which was launched the very next month. The PC had learned many lessons from the Datamaster, keeping what was good and throwing out what wasn’t. The PC changed the world, the Datamaster found modest sales in die-hard IBM shops.

The Selectric was arguably the ultimate electric typewriter, and while the Datamaster wasn’t the ultimate microcomputer it paved the way for what arguably evolved into one. Both devices are quite collectable, although the Datamaster is much rarer than the Selectric. Out of the two, the Selectric might still be of more practical use... and your children may well never have seen anything quite like a typewriter before.

Image credits:
Marcin Wichary via Flickr – CC BY 2.0
Steve Lodefink via Flickr - CC BY 2.0



Monday, 26 July 2021

Donkey Kong (1981)

Introduced July 1981

Donkey Kong was the arcade game that established Nintendo as a success in the North American market – introducing two of their most iconic characters in the process. But unlike many other games from the golden age of arcades, the development story for Donkey Kong begins in failure.

Donkey Kong detail
Donkey Kong detail

In 1980, Nintendo had attempted to break into the US with a game called Radar Scope which was a 3D space shoot-‘em-up with some advanced graphics for the time. 3000 machines were built and shipped to the States, but sales were poor and 2000 of the cabinets were unsold, prompting a financial crisis for Nintendo.

Donkey Kong was developed initially as a way to reuse the existing cabinets. Instead of a space-based game, this was a platform game where an Italian plumber attempts to climb to the top of the level while being bombarded by barrels thrown down by a primate.

The names of these characters? If you hadn’t guessed, they were Mario and Donkey Kong. Unusually for a game of the time, the characters came first and the game followed after. This process eventually meant that Nintendo had a cast of digital stars they could put into their own games which helped them grow in popularity even more.

Nintendo reworked the logic board from the original Radar Scope game, Donkey Kong had simpler hardware requirement than the shoot-‘em-up, it still possessed colourful graphics, sound effects and music all powered by a Z80 CPU. It wasn’t hard to port it to the booming microcomputer marketplace, and licensed and unlicensed clones were soon everywhere.

Donkey Kong arcade machine
Donkey Kong arcade machine

As well as direct sequels (many of which were based on the same hardware) a whole range of Nintendo games built on the characters and added many more. Mario in particular went on to star in what is probably the most successful video game franchise ever including Super Mario Bros, Mario Kart and many others. Donkey Kong starred in Donkey Kong Country and many other games, often crossing over with Mario.

It’s quite possible that if Nintendo hadn’t been sitting on a couple of thousand Radar Scope machines that such a novel concept might not have been risked. As it was, the descendants of the original Donkey Kong game gave Nintendo a unique edge in the future… which turned out to be not just shoot-‘em-ups after all.

Image credits:
Wordshore via Flickr - CC BY-NC-ND 2.0
Microsiervos via Flickr – CC BY 2.0


Monday, 19 July 2021

Ericsson T68 (2001)

Introduced July 2001

By the middle of 2001 the golden age of mobile phone design was beginning. New features were added to phones rapidly, and every handset managed to look very different from rivals. The next few years would see a wave of innovation – but for Ericsson, 2001 was also its swansong as a mobile phone brand.

Ericsson had produced a range of successful (and mostly very compact) phones but was losing money on the operation in a big way. Despite this, Ericsson continued to launch great new products and the Ericsson T68m (usually referred to as just the “T68”) was one of them. A diminutive 84 gram device, it packed in more features than rivals to create a very desirable handset.

This Ericsson T68m has seen better days
This Ericsson T68m has seen better days

One of the main selling points was Bluetooth – one of the first phones to feature this technology. It also had a colour screen, tri-band GSM, GPRS packet data, a WAP browser, predictive text, a bitmap editor and a bunch of included games. A camera – the MCA-25 CommuniCam – was available as a clip-on extra, again making it one of the first phones to feature that particular technology.

Not long after the launch of the T68, Ericsson merged their mobile phone business with Sony to create Sony Ericsson. The T68 received a slight cosmetic makeover and had a software update to become the Sony Ericsson T68i, the first phone to carry that branding. Eventually the camera add-on became a standard accessory, helping to popularise the idea of cameraphones.

Sony Ericsson T68i with Communicam
Sony Ericsson T68i with Communicam

When it eventually arrived, the replacement for the T68 was the stylish T610 and there was a successful run of handsets after that. Today, used prices for the T68i and T68m are pretty healthy with really good ones selling for £100 or more, although sub-£50 is more common. The Communicam camera add-on is available as new old stock from £50 or more, all pretty healthy for a 20 year old feature phone..

Image credits:
The Norwegian Telecom Musuem via Wikimedia Commons - CC BY-SA 4.0
Science Museum Group - CC BY-NC-SA 4.0


Tuesday, 6 July 2021

Renault 4 (1961)

Introduced July 1961

One of world’s most successful single models of car, the Renault 4 sold over eight million units in 33 years of production. It was an enduring success, utilising several technologies which were novel in the 1960s but commonplace in later years.

Although the Renault 4 is shaped like a small station wagon or estate car, it was actually the world’s first mass-produced hatchback. It was also front-wheel drive, at a time when almost everything else on the road was rear wheel drive. Indeed, the engine was in the front as well when rear-engined cars were still a thing.

Renault 4
Renault 4


The design was modern by early 1960s standards, and the target market was people who up until then had been buying the Citroën 2CV. Despite the rival 2CV having been introduced in 1948, it was still a strong seller due to its practicality and simplicity. However, the Renault 4 offered more power, more comfort and lower maintenance costs.

Unlike modern cars, the Renault 4 is built on an independent chassis with the body being placed on top. The chassis provided all the structural strength, allowing more windows and thinner pillars in the car itself giving better visibility. A range of engines were available – the smallest was in the Renault 3 (fundamentally the same car as the Renault 4), giving 22 horsepower. The Renault 4 had up to 32 horsepower. The rival 2CV thrashed around on just 12 horsepower at the time.

It was a practical car, and comfortable too. Although it maybe lacked the charm of the 2CV, it went on to be a massive sales success worldwide. Licence-built versions of the Renault 4 were made in such diverse countries as Argentina, Ireland, Morocco, Australia, Mexico and Yugoslavia. There was a popular van ("fourgonnette") version, plus a pickup and dozens of quirky custom versions made by converters and enthusiasts.

Renault 4 fourgonnette
Renault 4 fourgonnette

After the Renault 4’s launch came a host of other front-wheel drive hatchbacks, both from Renault and other manufacturers. The 4 lingered on though, with French production going on until 1992 (and until 1994 in Slovenia). Eventually it was replaced with the first-generation Twingo which successfully built upon the 4’s design philosophy – becoming a modern classic in its own right.

Today the Renault 4 is a rare sight on British roads – much rarer than the rival 2CV – with prices starting at just a few thousand pounds for a slice of Gallic charm. 

Image credits:
Spline Splinson via Wikimedia Commons – CC BY 2.0
Gzzz via Wikimedia Commons – CC BY-SA 3.0


Sunday, 27 June 2021

Chromebook (2011)

Introduced June 2011

Chromebooks are boring. Not as sleek as a tablet, not as powerful as a laptop. They’re for people who think a chicken korma might be a bit spicy and whose automobile of choice is an off-brand South-East Asian compact people carrier which just reliably gets them, their family and the dog from A to B with the minimum of fuss.

Based on Google’s Chrome OS - derived from the open source (but still largely Google) Chromium OS which is essentially a lightweight version of Linux – Chromebooks are inexpensive laptop-like devices designed for running web applications and a somewhat limited range of native apps, plus on many devices that ability to run applications designed for Android.

Currently most Chromebooks run on Intel-compatible processors, especially lower-end Celeron CPUs. Alternatively some variant of the ARM processor can be used, but these seem to be losing popularity. Like laptops there are a variety of configurations, mostly different screen sizes and CPUs. Internal storage is usually very limited as it is expected that most storage will be done in Google’s cloud. Similarly, there’s only limited functionality available without an internet connection.


HP Somethingorother
HP Somethingorother

Bland? Well, when you consider that people shell out thousands for high-end devices such as Macbooks but only use them for web browsing, they are certainly better value for money… in the same way that most expensive four-wheel drive SUVs never go further off the road than the supermarket car park. Since most Chromebooks tend to cost a few hundred pounds, they are usually a decent value proposition.

There are irritations, one of which being that Google got rid of the CAPS LOCK key to replace it with a search button. Printing can be difficult, but anyone who has tried to print from a smartphone will know that feeling too. You can’t run heavyweight native apps either because the hardware is generally underpowered and there is minimal storage space, but Chromebooks don’t pretend to be laptops. On the plus side they are inexpensive and have a real keyboard which makes them more suitable for real work than a tablet.

One key advantage is security – Windows devices are plagued with viruses and other malware, and so are Macs and even iOS and Android devices to a lesser extent. Although Chromebooks aren’t to security flaws, for all practical purposes they are much safer than using a traditional PC. On the other hand, software updates for Chromebook models have a much shorter lifespan than (say) a Windows PC, especially in early models which led to some hardware becoming obsolete in just a few years.


Chromebooks in a school environment
Chromebooks in a school environment


Did I mention they were boring? Well, really they are... but Chrome OS has a greater market share than the Mac (if you count a Chromebook as a laptop and not a door wedge), and in markets such as education they have a much larger share still. Is the idea a success? It’s a slow burn to be sure, but it does seem that Google and its partners have managed to come up with a viable alternative to Windows, Macs and tablets. Will they be around for another ten years? Given Google's habit of dropping products I would not bet on it..

Image credits:
BUF Simrishamn via Flickr - CC BY 2.0
TechnologyGuide TestLab via Flickr - CC BY 2.0



Sunday, 20 June 2021

Frogger vs Centipede (1981)

Introduced June 1981

Early popular arcade games tended to be space-themed shoot-‘em-ups, which tended to appeal to male customers. However, games such as Pac-Man had a much broader audience and were especially popular with female players.

Fighting for a share of this market - and introduced roughly at the same time as each other – were Frogger (by Konami and Sega) and Atari’s Centipede. Both these games are regarded as classics of the golden age of arcade machines, but both had very different gameplay.

The origin story for Frogger is as cute as the game itself. Konami employee Akira Hashimoto was watching a frog trying to cross the road from his car, and was thinking about the difficulties the poor creature was having… which led to the inspiration for creating the game. Only the poor old frog in Frogger has an even tougher time.


Frogger machine from Seinfeld
Frogger machine from Seinfeld


In the game, the player starts at the bottom of the screen and tries to make it to the frogs’ homes at the top. To do this, the frog has to cross several lanes of traffic, and then cross a river on floating logs and diving turtles while avoiding alligators. There are many ways to die. Colourful graphics and a catchy soundtrack added to the appeal of the game, and it was a huge hit.

Centipede was another animal-themed game, but very different in execution. From a gameplay perspective, this was closer to a traditional shooter game, but here the adversaries were various bugs that you had to defend yourself against, primarily a long centipede which wound its way down the screen and which would split up if you shot it. Fleas, spiders and scorpions appeared with different behaviours, and the playfield was full of mushrooms which changed the course of the centipede when it hit.


Atari Centipede
Atari Centipede

Like Frogger, Centipede was a huge hit particularly with female players. Both games were widely ported – officially and unofficially – to the booming home computer and console markets. Indeed, both arcade machines shared many hardware parts with theses home machines – Frogger ran on a Zilog Z80 with the versatile AY-3-8910 sound chip and Centipede used the MOS Technology 6502 with Atari’s own POKEY sound chips which found their way into every Atari product of the time. This symmetry in hardware capabilities allowed this generation of video games to be a huge hit away from the arcades. Eventually powerful home computers and then consoles would end the golden age of arcades but by 1981 that was still some way off…

Image credits:
Arturo Pardavila III via Wikimedia Commons - CC BY 2.0
Matt M via Flickr – CC BY-NC-ND 2.0