Wednesday, 31 January 2018

1970s Computer Adverts... an occasional series

Need to work on the name.

Sunday, 28 January 2018

Bell Labs' Holmdel Computing Center training videos

What was intended as a training video for new employees to Bell Labs' iconic Holmdel Computing Center (which after all was where the likes of C and Unix originated) in 1973 is now a fascinating insight to high-end computing back in the pre-PC age and a nostalgia fest of old iron. This reminds me of my minicomputer days at university, writing programmes on a Prime using a Volker-Craig terminal and then going to the library to collect my print outs on big fan fold paper...

Wednesday, 24 January 2018

Jupiter Ace

One characteristic was common to the microcomputers of the late 1970s and early 1980s, they all tended to have BASIC included on a system ROM. Well there was one notable exception, the Jupiter Ace. It was the first home computer to be based on Forth instead of BASIC [1]. The Ace was developed by British company Jupiter Cantab and released in 1982.

Apart from Forth the Ace was quite typical of the period having a Z80A CPU and 1KB of RAM, in terms of form it was not unlike the Sinclair ZX81 though a different colour of course and with rubber keys. It also had quite a different internal arrangement not unlike the Spectrum (the designers were ex-Sinclair who had worked on the ZX81 and Spectrum).

Forth was chosen as it was considered ideal for a computer like the Ace being fast and compact and a structured language compared to the BASICs of the time. Unfortunately the Ace didn't catch on, the lack of BASIC ended up being a massive hinderance not a bonus. When you are swimming against the flow you need to be really really good and the Ace, despite some nice features, was not. Its graphics were low resolution black and white (64x48) and it lacked decent sound. Forth was also not as easy for beginners to learn compared to BASIC.

For the average home user it was not really that attractive though the inclusion of Forth and the ability to expand the Ace to 51K meant it had appeal to hobbyists. However there were not enough of them to make it a hit.

Around 5000 of the original Ace and 800 of the Ace 4000 with an improved case are reported to have been sold. The Ace was discontinued in 1984.

[1] Max Philips, Microcomputer Catalogue (Marshall Cavendish, 1983) p. 14

Sunday, 21 January 2018

Apple Macintosh Keyboards (M0110 and M0110A)

A Macintosh is nothing without a mouse but also is a bit pointless without a keyboard as well. M0110 was the original Macintosh keyboard dating from 1984. It was connected to the Mac via a telephone style connector. It isn't a bad keyboard to be honest with a reasonable feel and has a nice chunky solid feel about it.

Apple wanted people to only use the mouse to select items so the keyboard has no arrow keys. It also didn't have a numeric keypad, a separate keypad was available for the Mac.

Later on in 1986 came with the M0110A keyboard for the Macintosh Plus and included the missing keypad. Both keyboards are displayed below, the M0110A is a fair bit bigger and also has arrow keys though has a similar feel.

Saturday, 20 January 2018

Thursday, 18 January 2018

ALGOL (ALGOrithmic Language)

ALGOL is a family of high-level programming languages originally developed in the late 1950s. ALGOL is a mathematical language [1] indeed the name comes from ALGOrithmic Language [2]. The language has had a major influence on modern languages like C and Pascal. Modern languages like these are sometimes referred to as "Algol-like".

ALGOL was originally created at a committee of American and European computer scientists in 1958. It was developed to try and rectify what were saw as problems with other early languages like  FORTRAN. ALGOL has been a major research and teaching language and became the standard for the publication of algorithms. This ensured its influence on future language development.

There have been three standards of ALGOL, the first was ALGOL 58 as originally defined. It was followed by ALGOL 60 and finally ALGOL 68 which added new elements to the language. However ALGOL 60 remained the most popular version as some thought the ALGOL 68 changes went a bit too far and could be considered a whole new language.

As well as usage in academia and research examples of ALGOL usage include software on the Soviet Buran space shuttle, computer systems of the Royal Air Force in the Cold War and a number of operating systems from companies like ICL and Burroughs. It is still used on Unisys mainframes as a system language and elsewhere on "legacy" systems (including some UK government departments).

Finally lets look at some code examples of ALGOL 60. Even if you are unfamiliar with the language and never seen it before if you know a bit of C, Pascal or similar then ALGOL is perfectly understandable:

for n:= 5 step 1 until 10 do
begin x:=n/5

if fract(p) > 0.5 then a := p;

day := day + days[month];

One thing ALGOL 60 did lack was input and output facilities. This was left to individual implementations of the language and thus differed between computer manufacturers.

[1] Eric Foxley & Henry R. Neave, A First Course in ALGOL 60 (Addison-Wesley, 1968) p. 5
[2] Graham C. Lester, Data Processing Vol 1: Hardware & Programming (Polytech, 1980) p. 203

Tuesday, 16 January 2018

Dr Who advertises Prime

As said in the history of Prime Computer, the minicomputer manufacturer was pretty big in its heyday in the early 1980s. So much so they even got the then-Dr Who Tom Baker and his assistant Romana (Lalla Ward) to make some adverts for them!

Friday, 12 January 2018

Macintosh External Floppy Drive (M0130)

The Macintosh came with a built-in 3.5" floppy drive - but in the days before hard drives being commonplace (unless you had a lot of money) having two floppy drives was a boon. M0130 was an external floppy drive for the original Macintosh, the follow-on 512K, the Mac Plus and the SE. It would not work with an Apple II.

The disk drive used 400K floppies formatted in the Macintosh File System format. And came in a nice neat beige box to match the original Mac.

Monday, 8 January 2018

Floppy disks

The floppy disk is a very rare beast these days, though the look of them is still very well known. The image of one is used on many applications to represent "Save" (and the joke is that when kids see a real floppy disk they think someone has made a model of the Save icon). Floppy disks are a portable data storage medium which first appeared in the 1960s and early 1970s in 8" form. Over the years the floppy disk has gradually decreased in physical size but the amount of storage held on it has increased dramatically.

Floppy disks is a magnetic storage medium, the data being encoded on a disk which is protected by an exterior cover or sleeve. Early covers were soft and flexible (hence floppy) sleeves though later disks were rigid plastic enclosures.
Some of my floppy disks... or 3-D printed save icons if you prefer

The 5.25" floppy disk first appeared in the mid-1970s and held sway as the major data storage format for personal computers well into the 1980s. In the mid-1980s the 3.5" floppy disk appeared and this remained the standard disk format until the concept of the disk itself was obsolete in the early 2000s. There were smaller disks formats around such as the 2" floppy used on the the Zenith minisport (a photo of my one below) though these did not find much favour.
Zenith minisport

Indeed in the case of the Zenith the 2" disks were hard to find (and pretty expensive if you did) so an external 3.5" floppy disk drive tended to be used instead. This reduced the usefulness of the computer as a "portable" of course.

The end of the floppy disk drive as the major removable storage medium came fairly quick. The Apple iMac was released in 1998 and was the first high-profile personal computer from a major manufacturer without a floppy disk drive. Although external drives sold well at first many people (including myself) learned to live without a floppy disk drive. By the 2000s computers were increasingly being sold without the drives. A major reason being the limited capacity of floppy disks and the rise of better alternatives.

The 3.5" floppy drive usually held 720KB or 1.4MB (earlier floppies held less, some could hold as much as 2.8MB). As software grew more complicated and powerful file sizes increased dramatically - floppy disks became an inconvenient as a medium for software installation. Major pieces of software such as OS/2 came on as many as 30 disks (i have read that there was a floppy disk release of Windows XP that came on 250 disks though cannot verify if that is true), even applications like Quattro Pro came on over half a dozen. Installing software, and having to switch disks every few minutes was a pain - especially in a commercial environment. It became much easier to install off a CD-ROM, and later over the network.

Using floppies to transfer files between computers was very common, even in the same office before local area networks became ubiquitous. Such means of transfer was jokingly known as a "sneakernet".

Saving your work to floppy became increasingly inconvenient as file sizes increased too. Even a virtually empty Word file can be a few 100KB now. The Photoshop file of this blog's header is 1.1MB, and so would still fit on a high density floppy disk though you would have little space left for anything else! People did transfer files bigger than the capacity of a single floppy as there were ways of getting around this such as using split archives which chopped a file up into "floppy-able" parts which could then be combined on the target machine.

Alternative disk technologies to the floppy disk such as the Iomega Zip (which could typically hold 80MB) became popular in the late 1980s and 90s as did CD-RW burners though no alternative format ever approached the popularity of the basic floppy. Now you would be hard pressed to find a computer with any sort of drive, even CD/DVD drives are becoming rare. The network (that mysterious "cloud") is where all the data appears to be now.

Sunday, 7 January 2018

Tektronix 4404 Smalltalk Demo

Here is a fascinating demo of Smalltalk running on the Tektronix 4404. Smalltalk is a programming language developed in the early 1970s at Xerox PARC and was hugely influential in the development of object orientated programming and graphical user interfaces. There are indeed elements of the interface shown in the video still in Mac OSX nowadays (the browser for example). However the freedom and flexibility of the interface seems far beyond what we are allowed to do these days.

Thursday, 4 January 2018

Monday, 1 January 2018

Return of the TwiggyMac

The Twiggy Mac is the stuff of myth surely? The Apple Macintosh, up until a fairly late stage in the project (which was finally released in 1984 of course) was going to use the same 5 1/4 inch "Twiggy" disk drive as used in the Apple Lisa. Unfortunately the Twiggy drive was rubbish and often failed. Luckily Sony had just bought out their new 3.5 inch floppy drive format and the rest was history...

It was assumed that none of the Twiggy drive equipped Macintosh prototypes had survived as Apple had had them all recalled and destroyed in 1983. However one was found and later on another one turned up too!

After some restoration work the Twiggy Macs now work again and could boot from the original Twiggy system disks which included a beta version of Mac OS from August 1983. This version of the eventual first release of Mac OS included some intriguing differences from the final version including "Steve sez" in dialogue boxes. The whole story is recounted in the highly enjoyable Twiggy Mac website.
Heres how it ended up looking, my 512K