Tag Archives: porting


This is the first and ongoing phase (as of Mar. 2014). While the main purpose of Sköll is to generally get the original source to compile on Solaris (v8) it also has several sub-tasks:

Clean-up code
Smooth edges

Compile the original source

Several makefiles needed some adjustments to work with gcc (instead of suns own cc), also some tricky formatting f*ck ups needed to be corrected – (gnu)make is much more picky about this than whatever make they used back then.

Strip unnecessary parts

It’s not identified which parts are completely unnecessary, but the TI DSP code is something which can definitely go.
Other points might need to be discussed, e.g. what should happen to some very special servers (i.e. Terminalserver in Helios lingo) like SUN3 or ACORN R140?

Smoothing the edges

There are multiple strange code-constructs which should be cleaned – they lead back to buggy and awkward MSDOS compilers which needed some workarounds

Here are some examples:

The code is full of #define eq == defines. I was told that was a workaround for the “==” vs “=” issue in conditional expressions. Modern compilers warn you when a condition looks like an assignment, the Microsoft compiler they were using at the time didn’t.. Doh!

Then there’s #define elif(x) else if(x). WTF!? Well, this roots from BCPL, the ancestor of C. Most of the core-devs at Perihelion studied at Cambridge University where BCPL was invented and was used well into the 1980s. In addition to the standard if() and while() constructs, it also had unless() and until() statements, as well as elif().
To them used to these constructs, the code was more readable and boy, they do get used throughout the Helios sources way too much.


The Plan

Welcome fellow reader of ‘el Reg’... you might have come here due to this The Register post from Dec. 6th 2021… thanks for the free ad chaps!

Yeah, it is a somewhat dusty project but that might be due to the fact that I’m working on this alone. Since years. On and off… more off than on honestly. Because there’s no fun in soliloquies.
But I will be happy to chime in again as soon I see active forks on github

So have fun browsing this time-killing page… 150+ posts are waiting to make you wonder where the time went 😉

There’s a rough schedule where this project should go, given there are enough clever people joining in or at least display a certain degree of interest. So there’s a skech of the main-phases, aka “The Plan”  (without dates):


As said in the intro, Sköll is about “catching” the sun, i.e. get the original Helios 1.31 sources to compile on Solaris. This includes

  • cleaning up the code
  • weed out unneccesary parts (e.g. the TI DSP code)
  • smooth the edges (There are multiple strange code-constructs which should be cleaned)
  • get a general understanding of it all


Next phase/release/step after that will be “Hati”, the other wolf who chases the moon – less mystic, this means getting the “Helios-Sköll” sources to compile on Linux.
Some tools already do, e.g. the Transputer Assembler ‘as’… the Norcroft-C compiler is another story.

And as we all know, when Sköll and Hati finally managed to hunt down the sun and the moon, the world will be destroyed and reborn:


It’s certainly not the end of the world. I leave it open for now what that means in terms of Helios, but maybe there will be a critical mass of participants in the community to push “Helios-Hati” forward into version 1.4 running on x86 or current ARM implementations like Raspberry Pi and the like?

Secondary theater of War

Well, then there’s another part of Helios which needs some attention: The server.
This is the piece of software handling the communication between the Host (e.g. your DOS Box) and the connected Helios System (e.g. your Transputer(farm)).
There are several Server sources in the [HeliosRoot/]ioproc/server folder like DOS, Windows, RS6000, HP9000, Interactive UNIX, Sun3/4/i386, SCO etc… obviously all supporting very old versions of their OSes, e.g. Windows 3.x or Solaris 2.

So this part will need some love, too. I will mainly concentrate on DOS (that’s the [HeliosRoot/]ioproc/server/ibm folder), because that’s what I use to talk to Helios.
To support more recent ways of communication than ISA/SBUS/VME-cards, we have to create a new server, for example for Mikes USB-Link Interface.