Anyone remember the team used a model railway as a demonstration in the early days of Erlang development?

I did a forum search for “railway” and this is where I landed!

What I’m actually seeking is some reference to the early days of Erlang development, where - if my memory hasn’t failed me - the team used a model railway as a demonstrator. Anyone recall this, or better yet, have a link to a resource that mentions it?

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I’ve split your post into a new thread Phil as more people will see it this way :smiley:

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The history of Erlang mentions it on page 6-13:

Another memorable event of 1993 was the Erlang display at the
trade fair held in October in Stockholm. The main demonstrator at
the display was a program which simultaneously controlled a small
telephone exchange15 and a model train. Figure 8 shows Robert
Virding hard at work in the Lab programming the model train.
To the immediate right of the computer behind the train set is the
MD100 LIM. Following the trade fair, for several years, we used
the train set for programming exercises in Erlang courses, until the
points wore out through excessive use. While the control software
was fault-tolerant, the hardware was far less reliable and we were
plagued with small mechanical problems.



What do you want to know?
Robert Virding wrote the control logic for the model railway (Märklin) and Magnus Fröberg and myself wrote the GUI interface.

For the GUI interface we created a simple “language” where each railway piece, which had an ID in the Märklin catalog, could be put in a list which we then traversed and draw an exact replica (scaled down) of what it looked on Roberts desk which hosted the physical railway (including burnmarks we later found out to Bjarnes horror… :stuck_out_tongue: ).

Apart from presenting it at that large fair in Älvsjö, we also used the railway as an student exercise for the Erlang courses that we held in the Lab.

(Bjarne and myself at the IT fair in Älvsjö)

Cheers, Tobbe


there’s one mention with a color picture here:


That’s the picture I had in mind!

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