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Jet 80


Kent Olsson, who was in the team that developed the operating system of Jet80, adds the following;

Operating System for Jet

The company Vendel Data in Östersund was founded by me, Kent Olsson, Mats Svensson and Mats ”Matte” Eriksson. These gentlemen both originated from MIWA Electronics in Nynäshamn.

Mats Svensson was oriented at sales, Mats Eriksson was a hardware engineer, whilst I was fully focused on software.

MIWA was one of the importers of, at the time being, the expensive Onyx ”mini-computers”, and our ambition was to in some way develop a concept by which we could press down the pricing of the machines, enabling ”the common man” to buy the computer.

Onyx had an operating system based on Data General’s Basic Four or Business Basic. A plethora of so called ”butter-and-bread routines”, written in Business Basic, existed for, among others, mini-computers like DG-NOVA, TDS, Onyx etc.

It was when we scanned the Swedish market that we came into contact with one of the early prototypes of Jet80.

The contact came from a friend from the Scandia Metrics-era; Göran Waernér. During that time, Jet80 was provided with the operative system CP/M, just like all other micro computers worthy of mention. CP/M was ”like the back of my hand”, since I on earlier occasion had worked together with Gary Kindall at Digital Research.

We immediately saw the potential of the Jet80. It had a powerful Z-80, Zilog's SIO, PIO as well as DMA and plenty of memory. The problem was that there were no applications that could make it anything but yet another CP/M-based computer for a SINGLE user.

I then wrote a Business Basic interpreter/environment for the machine. I did that so that the computer could be booted straight into Business Basic without switching to CP/M. The SIO had two channels, which made it possible to run two terminals at the same time, toward the same Jet-computer.

In that way the micro computer Jet80 got access to all applications written for the ”mini-computers” TDS, DG, Onyx etc. It was anything from client accounting to programs for travel agencies. The Business Basic interpreter was totally compatible with the MAI's Basic Four.

We then brought the protorype to Karl-Johan Börjesson and presented to him the multi user system, upon which he exploded with delight. Suddenly the Jet80 could become useable also for others than solely ”computer freaks”. Furthermore, WE got access to a cheap micro computer to replace the ”mini-computer” Onyx. The fact that is was Swedish gave an extra touch of joy.

The Jet80 could now be run by two multiple users, but this was not enough. Peter Löthman then constructed a ”piggyback” to the Jet80, which enabled two additional terminals to be run. Now we had a full-fledged multiple user system for administrative routines. The problems were word processing, spreadsheets etc. For that, one needed to re-boot the machine in CP/M, but then the multiple user system vanished.

Karl-Johan Börjesson, at the same time, had been thinking about schools, and wanted to develop a network-based environment to implement the Jet-computers in schools. The concern was CP/M, that had been constructed for a SINGLE user.

The Business Basic environment enabled us to run four users, but no more. Furthermore, there was a slight chances of getting the schools to run Business Basic, which was developed for business applications. There were, thus, no alternatives to multiple user systems for Jet-80, and Karl-Johan Börjesson wanted everything to be ”fully Swedish”.

The Jet-80 would be ”The Swedish School Computer”, and that was it. It then fell upon me to create the new environment for Jet-80. The goal was to create a MULTIPLE USER SYSTEM compatible with CP/M, so to enable us to run ”standard applications”, but also to be able to have a Business Basic interpretor so that we could use the full scale and powerful business applications.

The internal code name was V/NET, or Vendel Net. Officially, it later became JetNet. John Rehn brilliantly constructed the communication interface. I developed the operative system and Staffan Wictorin, who was Karl-Johan Börjesson’s partner, wrote large parts of BIOS. He, by the way, also wrote main parts of BIOS for the standard porting of the initial CP/M.

Vendel Data was located in Östersund, and delivery was carried out daily through modem. I sent the ”insanely large files” of, at times, up to 600 kilobyte to Peter Löthman’s DEC-10, ”Kicki”, to which I had an account and line. Jet in Danderyd then downloaded these to Danderyd for testing.

V/NET, or JetNet, so became the first Swedish multiple user system for micro computers. At that time, it was practically the ”Wild West”. Karl-Johan Börjesson was utterly enthusiastic and stomped about cheering everybody on.

Anyway, we were very euphoric about the Jet-80, and we were assured that it would out-compete IBM’s ”toy computers”. Vendel Data then had become synonomous with Jet Computer, and we had no other assignments than servinng Jet with operative systems.

Vendel Data went bankrupt when Jet went ”into the closet” in the shadow of the grand venture of Compis And IBM. After this belly landing, I was in great debt. V/Net and all source code through dim routes ended up at Prosoft who created BRIDOS out of the code. Vendel Data started again under other directives in Farsta Strand, and as far as I know, they are still there.

It was all crazy, and some faith in yourself is needed if you venture to create a multiple user system that is to ”out-compete IBM”. Karl-Johan Börjesson was the driving force.

The Jet computer was later equipped with 128K ram in two banks, and then it really got fun to create enviroments for it. What more, it later came with a Z-800 that was super-fast. I remember lying on the floor, laughing myself to tears when I’ve had the first IBM computer delivered and compared its speed with the Jet-80.

”IBM should keep to typing machines, this computer will never become anything big”

That lesson has followed me through life.

John Rehn, who was in the team that developed Jet 80, adds the following;

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