Tuesday 2 May 2017

Commodore PET 40 year anniversary theme for E2B

The Commodore PET was first announced, and later released, in 1977 (40 years ago).

It was a complete All-In-One computer with built-in keyboard, monitor and storage media and was months ahead of the Apple II or TRS80 (Trash80!). In essence, it was an early Macintosh and was one of the first computers suitable for business use, rather than hobbyists.

On a side note, the PET never really took off in France for some reason (apparently 'pet' is slang for another word!). Later, Commodore released the VIC, which did not sell too well in Germany either, as it sounded like you were asking for a 'fick' which is German for something quite different!

At the time, my family ran a small 12th-Century hotel in Oxford, now made famous by my late friend Colin Dexter, who wrote the world famous Inspector Morse books (Colin reviewed examination papers with his colleagues, ate, drank and sometimes slept at our hotel). Our hotel was even featured on the front cover of one of the paperback versions of 'The Secret of Annexe 3'. Colin even gave me a few first edition signed copies of various Inspector Morse books over the years, which I guess must be worth a few pennies now!

When I was a boy, I was interested in computers and had built and programmed several of my own, but I really wanted a new Commodore PET...

Now, payroll software for the PET was non-existent at that time, but in early 1978 I persuaded my father to buy me a new PET, on the promise that I would write a complete staff wages program for the hotel. I explained that this would save him hours of pouring over his H.M. Gov tax tables and Kalamazoo wages sheets every week to work out the pay packets for the 12+ staff we had working at the hotel!


I eventually got the PET and (after playing one or two games), I spent many hours writing, testing and perfecting the payroll program for him (written in Basic).

When I had finished it, I showed him how he could just select the staff member's name from a list, put in the number of hours they worked and instantly see their wages for the week so that he could make up the staff pay packets. It also displayed the National Insurance deductions (his and theirs) and cumulative Gross, Net and Tax figures. He could add or delete staff names. It also had to account for different hourly rates for different types of work. The program and the results were loaded from, and saved to, the built-in audio cassette recorder (which took about 10 minutes!).

The problem was, he didn't trust it because the final figures were always very slightly different from the figures that he obtained when he used the tax tables manually. It turned out that the tax tables were always rounded down, whereas the PET calculations were extremely accurate (to the nearest penny). He didn't like that!

So I had to revise the program to use the same rounding formula that the tax tables used (after I had worked out what the formula was that they used to make the tax tables!).

After about a month of running both systems in parallel, my father eventually trusted the payroll results and used it for many years (and even bought a printer).

To celebrate the 40th anniversary of the PET, I have made a new E2B theme, the Commodore_PET_THEME.zip file is available from the Themes folder on the E2B Alternate Downloads sites (copy the two files to the  \_ISO folder).

The E2B Commodore PET theme - Install Windows 10 to the Commodore PET (not really!)

After writing the payroll program, I had intended to write a hotel reservations program for the PET, however, I soon realised that the cassette system used by the PET to load and save data and programs was far too unreliable and slow.

In fact, the lack of fast and reliable storage held back the use of personal computers for small business use until cheap hard disks became available. In 1983 the IBM PC\XT included a whopping 10MB(!) internal hard disk, but the XT was rather too expensive for UK small businesses to invest in (especially as there was a lack of software for it). It was not until later IBM PCs, Compaq and AST  PCs started appearing that PCs for small business use started to become a viable proposition.

One of the biggest failings of the Sinclair computer range was the lack of reliable storage. The UK could have become a world leader in the home PC business if only they had realised that a home PC needed these qualities:

  1. Reliability
  2. Sturdy construction
  3. Fast and reliable storage
  4. Good quality keyboard and monitor
  5. Full documentation (programming, OS and hardware) to encourage software developers

It did not help that the affordable and thus highly popular Amstrad 2386 PC used the Seagate ST277R 5 1/4" 20MB hard disk which had a fatal thermal problem (off-track writes). Many people lost months of work because the disk drive heads had the nasty habit of writing data to the wrong track and thus irretrievably overwriting or corrupting sectors. Alan Sugar also writes about this in his autobiography (#ad) which I highly recommend as a good read.

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