What is IBM SNA System Network Architecture?

Another neat IBM promotional video from the early 1970s.

IBM System/3 Advert

A rather odd at times but fascinating advert for the IBM System/3 minicomputer.

More clicky fun

I have an obsession with loud clicky keyboards. I use a Tecknet mechanical switch keyboard with my Mac mini, of course have bought a number of typewriters this year, and now i have bought a mechanical switch Bluetooth keyboard for use with my MacBook Air. It is not quite as loud as the Tecknet but is very nice, i can also type very quickly on it already (i can almost touch type). The keyboard is an Epomaker NT68 and is recommended, if you like noise.

Evolution of the scroll bar

This is an interesting website showing the evolution of the GUI scroll bar from the earliest days of Xerox to the modern day. Personally i think the Mac scroll bar reached it's peak with System 7 and 8. The scroll bars of the current day are rather anemic. 

A tale of CD-ROM formats

As with most things in computing, with CD-ROMs there is a standard (ISO9660), but also other formats one of which was another defacto standard. 

When computing started using the then-new CD format for data storage in the early 1980s, a standard was needed for organising the data. In 1985 a number of leading computer companies came together to create the High Sierra format (named after the hotel where the companies' representatives met).

High Sierra became the defacto CD-ROM data format until the finalised ISO9660 standard a couple of years later. However, software support for the standard lagged it's introduction for a while which meant the High Sierra format continued to be used. As the format was supported even after ISO9660 replaced it, companies like Microsoft and IBM continued to publish CD-ROMs in High Sierra format well into the 1990s. This article is an interesting look at the format.

Not actually having an active computer with a CD-ROM anymore i don't know if my copy of OS/2 Warp is High Sierra or not, though as the follow-on version apparently was still in that format there is a good chance it is.

A room of old iron

A glorious photo of a computer lab from the Convair/General Dynamics Astronautics Atlas Negative Collection. Large disks, loud printers, what could be better?

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 and their derivatives which have gone on to dominate the world. 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 such as 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 includes the 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
end;

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

The joy of old computer fonts

This is a great selection of 1980s (and earlier) computer fonts from well-known microcomputers like the Apple II and C64 to some less well-known machines. The original bitmap fonts have been converted to Truetype so they can be used on modern computers for some retro fun. Below are some of the fonts used on the Apple Lisa.

Apple & Unix : The early years

Since 2001 and the release of MacOSX, the operating system of Apple Macintosh computers has been Unix based but this was not the first time Apple developed and released a Unix for the Mac. 

In 1988 Apple released A/UX which was based on Unix System, it came with a version of the Apple Mac graphical user interface and ran on select Motorola 68K Macs. It was able to run Mac and X-Windows applications. Unix commands could be run via a dialog box which also allowed the user to select command line options in a user friendly way. The initial version of A/UX included the System 6 Finder with the Finder switching to System 7's with A/UX version 3.0.

Despite the positive reaction to A/UX from some quarters, A/UX was never a great success for Apple and today remains in obscurity. Apple thought A/UX could help them get the Mac into big business and the growing enterprise market. Apple finally dropped A/UX in 1995, the already announced v4.0 never seeing the light of day.

This wasn't the end of Apple's pre-MacOSX Unix efforts though. In 1994 they released the Macintosh Application Environment for Solaris and HP/UX. It could allow Macintosh applications to be run on Unix computers from Sun and HP. It again used a version of the Mac OS 7 Finder and special tools for importing and exporting to and from the Mac and X environments. MAE was discontinued in 1998. Thus ending Apple's involvement with Unix... well for the time being...

Screenshot from WinWorld https://winworldpc.com/product/a-ux/3x

Welcoming Sophie

My Chromebook Pixel has had a good hard life but it has finally come time to replace it. The screen is flickering, the keyboard slightly broken and Google support ends later this year. The Pixel has been replaced by a MacBook Air. This is my first computer with an ARM based chip (not counting the various iPhones and iPads I have had in the past). Hopefully, Sophie (as she has been called) will have just as long a working life as the Pixel (though I will try and not break the keyboard on this one!)

Of course, I bought a Mac mini last year called Emily which remains my main workstation, whereas Sophie is my personal assistant. For the first time I have two new (or new-ish) computers to hand. Which is nice.

Apple beige

Apple Computer attracts the kind of obsessive attention to detail from users and fans which no other computer manufacturer has ever achieved. Let's face it, only Apple could drive someone to delve into great lengths to discover what actual colour the company's earliest computers were. They were supposed to be Apple beige but like everything else surviving examples (like my Apple IIe below - this model was a slightly darker beige than earlier Apple IIs by the way) may have shifted in colour after exposure to light. So, what actual colour was the beige these computers were created in during the late 1970s and early 1980s? The article is worth visiting alone for the photo of the Apple Computer beige touch-up paint jar, that must be a very very rare surviving Apple artifact!

IBM 360 and Social Security

A lovely little film which shows how the IBM 360 mainframe works behind the scenes at a Social Security office.

The strange beauty of historic computers

Wired have a great article on the sights and smells of historic computing, the strange beauty indeed of the "olden days" of computing : mainframes, minicomputers, line printers and other historic computing artifacts. Many of the computers and peripherals at places like the Computer History Museum in California (somewhere i must visit one day!) or at the National Museum of Computing in Bletchley (which i have been to) still work after being restored adding an extra dimension to the experience. The sound and heat of a punched card reader...

It was a very different tech world to now, a bigger world too. Computers filled huge rooms with printers being the size of small cars, plus tape units the size of wardrobes. That is part of the fascination i feel, its just so different to the computing we use now.

Unfortunately by the time i entered work the world was largely moving past the age of old iron, though i did get to use a Prime minicomputer at university. This was great fun but the closest i ever got to the hardware were the rooms full of dumb terminals and a large remote printer (though that made a wonderful noise). 

The biggest computer i've ever had physical access to is a HP PC server which was the size of a small fridge. Big but not the same as a room full of IBM 360 or an ICL...

Photo from Flickr Commons

Before Excel there was VisiCalc...

A nice little video about the creators of VisiCalc. I have blogged about this pioneering piece of software before.

Copland, the mythical beast unveiled

Copland was one of Apple's biggest failures. It was an attempt to bring MacOS up-to-date in the early to mid 1990s but after several years of expensive development and project chaos, Apple was left with a mess which would crash even if you blinked too fast. Copland was cancelled, not even making it to a proper developer release and Apple looked elsewhere for the future, which ended up being MacOSX...

But Copland has been lost to time, or has it? A few builds did make it out into the wild and on this blog the sheer horror of build D7E1 is revealed (yes it crashes a lot). It did introduce a lot of technology which made it into subsequent versions of MacOS however. To me Copland is a bit of a mythical beast so seeing this video is like seeing footage of Bigfoot walking down Erdington High Street.

Upgrading our systems

After eight successful years our Macbook (Miriam) has entered semi-retirement and has been replaced by Emily, who is a Mac Mini. We've gone back to a "desktop" style computer after a decade of laptops - one reason being Miriam, and the Macbook before her (Suzy), never actually moved from the desk. You can get more bang for your buck with a desktop computer, and a much bigger screen.

Emily is our first main computer without a traditional hard drive (it has an SSD) and no CD drive. Although Miriam's CD drive was hardly ever used especially in recent years, it will be interesting to see if the lack of a drive on the new computer will end up being a problem or not. Miriam is always available if we need to check a CD-ROM of course...

History of the Zip

The zip file format is one of those vital pieces of computer technology that often gets overlooked. In the early days of home computing disk space was limited and internet speeds were generally slow, therefore file compression was very important. A smaller file took up less disk space and less time to download.

As this interesting page on the history and technical details of the zip file format shows in the early days of home internet use Arc was the first popular compression software but in 1989 the zip format was created by Phil Katz and very quickly became the most popular method of data compression used by millions of users on many millions of files. It is still used to this day usually embedded into other software to save file sizes and also to tidy up collections of files into a single zip.

The age of the punched card

Before the advent of modern technologies like magnetic tape and video screens the most usual way to load a program on a computer was via punched tape or card. Of course this was at a time when computers typically filled rooms and were something few people had access to. Indeed computer time was limited and expensive and computers could only do one thing at a time. They couldn't sit around waiting for a programmer to type in his latest masterpiece while there was more important work to do such as the company payroll!

Therefore programs were entered offline using a separate system called a card or key punch such as the IBM 029. The programmer would enter their program (COBOL shown below) or job control instructions and these would be printed to cards, where a line of code (up to eighty characters) fitted on a card. Holes in the card and the absense of them representing the binary data.

Once the program was written the programmer would have a stack of cards, which for a standard data processing program could consist of hundreds of cards! These were handed over at the computer centre to be loaded onto the computer when it was free by one of the operators. Often this would be during the night. The programmer would return the next day to receive the print out and see if his program had worked or not! Punched cards remained the most usual way to load programs well into the 1970s, indeed IBM were still selling card punch machines in the 1980s.

Punched cards had their drawbacks compared to later storage media of course though were durable and human readable. Dropping a stack of cards was not the end of the world, though a labourious task putting them back in order!

Restoring a 6502

Restoring a microchip is much like any other kind of restoration, just on a smaller scale. This website details how a circuit board found in a barn (literally stinking of cow manure) contained a rare early MOS 6502 CPU from May 1976. The 6502 was extracted from the board, cleaned up and still works!

The 6502 is one of the iconic early CPUs of the microcomputer revolution in the 1970s being first produced in 1975, powering the likes of the Apple II (my IIe seen below). Amazingly the CPU is still produced today and used in many embedded systems.

Flickr-ing away?

Flickr has, for a long time, been one of the cornerstones of my online digital presence. This has especially been so as i have begun to travel around the country taking photos of... well anything and then blogging about it. I find Flickr vitally useful in finding anything among the tens of thousands of photos i have now taken. If i want some photos of a railway station or church, for example, its much easier to search through my photos online than try and find it on my Mac.

Therefore the doubts being expressed about the future of Flickr by it's current owners Smugmug have been worrying. If Flickr doesn't start paying fot itself then the service may cease to exist. Unfortunately the way they are aiming to try and do this is by large price rises. Prices have doubled since the last time i renewed my PRO subscription in 2018 and with more price rises on the way there was the offer for PROs to renew early at the old prices. Now my subscription wasn't due to expire until June but i decided to renew and now i no longer have to worry about it for just under thirty months.

That is if Flickr is still around then. There have been concerns about the services' future before especially towards the end of Yahoo's reign of error. Back then i began to take measures to prepare just in case Flickr died, i now have multiple back-ups (offline and online) of my photos. So if Flickr did die then i'd have the photos, though i'd lose all the metadata of course. Lets hope Smugmug can turn things around though i think how they have handled things leaves a lot to be desired...

It is hard to say for sure what the first photo I uploaded to Flickr back in 2006 was as i deleted some old ones but i think this rather fine picture of a bus is definitely one of the earliest.