Friday 22 June 2018

Thomson 8-bit computers, a history

In March 1986, my dad was in the market for a Thomson TO7/70. I have the circled classified ads in “Téo” issue 1 to prove that :)



TO7/70 with its chiclet keyboard and optical pen, courtesy of MO5.com

The “Plan Informatique pour Tous” was in full swing, and Thomson were supplying schools with micro-computers. My dad, as a primary school teacher, needed to know how to operate those computers, and eventually teach them to kids.

The first thing he showed us when he got the computer, on the living room TV, was a game called “Panic” or “Panique” where you controlled a missile, protecting a town from flying saucers that flew across the screen from either side, faster and faster as the game went on. I still haven't been able to locate this game again.

A couple of years later, the TO7/70 was replaced by a TO9, with a floppy disk, and my dad used that computer to write an educational software about top-down additions, as part of a training program run by the teachers schools (“Écoles Normales” renamed to “IUFM“ in 1990).

After months of nagging, and some spring cleaning, he found the listings of his educational software, which I've liberated, with his permission. I'm currently still working out how to generate floppy disks that are usable directly in emulators. But here's an early screenshot.


Later on, my dad got an IBM PC compatible, an Olivetti PC/1, on which I'd play a clone of Asteroids for hours, but that's another story. The TO9 got passed down to me, and after spending a full summer doing planning for my hot-dog and chips van business (I was 10 or 11, and I had weird hobbies already), and entering every game from the “102 Programmes pour...” series of books, the TO9 got put to the side at Christmas, replaced by a Sega Master System, using that same handy SCART connector on the Thomson monitor.

But how does this concern you. Well, I've worked with RetroManCave on a Minitel episode not too long ago, and he agreed to do a history of the Thomson micro-computers. I did a fair bit of the research and fact-checking, as well as some needed repairs to the (prototype!) hardware I managed to find for the occasion. The result is this first look at the history of Thomson.



Finally, if you fancy diving into the Thomson computers, there will be an episode coming shortly about the MO5E hardware, and some games worth running on it, on the same YouTube channel.

I'm currently working on bringing the “TeoTO8D emulator to Flathub, for Linux users. When that's ready, grab some games from the DCMOTO archival site, and have some fun!

I'll also be posting some nitty gritty details about Thomson repairs on my Micro Repairs Twitter feed for the more technically enclined among you.

Tuesday 12 June 2018

Fingerprint reader support, the second coming

Fingerprint readers are more and more common on Windows laptops, and hardware makers would really like to not have to make a separate SKU without the fingerprint reader just for Linux, if that fingerprint reader is unsupported there.

The original makers of those fingerprint readers just need to send patches to the libfprint Bugzilla, I hear you say, and the problem's solved!

But it turns out it's pretty difficult to write those new drivers, and those patches, without an insight on how the internals of libfprint work, and what all those internal, undocumented APIs mean.

Most of the drivers already present in libfprint are the results of reverse engineering, which means that none of them is a best-of-breed example of a driver, with all the unknown values and magic numbers.

Let's try to fix all this!

Step 1: fail faster

When you're writing a driver, the last thing you want is to have to wait for your compilation to fail. We ported libfprint to meson and shaved off a significant amount of time from a successful compilation. We also reduced the number of places where new drivers need to be declared to be added to the compilation.

Step 2: make it clearer

While doxygen is nice because it requires very little scaffolding to generate API documentation, the output is also not up to the level we expect. We ported the documentation to gtk-doc, which has a more readable page layout, easy support for cross-references, and gives us more control over how introductory paragraphs are laid out. See the before and after for yourselves.

Step 3: fail elsewhere

You created your patch locally, tested it out, and it's ready to go! But you don't know about git-bz, and you ended up attaching a patch file which you uploaded. Except you uploaded the wrong patch. Or the patch with the right name but from the wrong directory. Or you know git-bz but used the wrong commit id and uploaded another unrelated patch. This is all a bit too much.

We migrated our bugs and repository for both libfprint and fprintd to Freedesktop.org's GitLab. Merge Requests are automatically built, discussions are easier to follow!

Step 4: show it to me

Now that we have spiffy documentation, unified bug, patches and sources under one roof, we need to modernise our website. We used GitLab's CI/CD integration to generate our website from sources, including creating API documentation and listing supported devices from git master, to reduce the need to search the sources for that information.

Step 5: simplify

This process has started, but isn't finished yet. We're slowly splitting up the internal API between "internal internal" (what the library uses to work internally) and "internal for drivers" which we eventually hope to document to make writing drivers easier. This is partially done, but will need a lot more work in the coming months.

TL;DR: We migrated libfprint to meson, gtk-doc, GitLab, added a CI, and are writing docs for driver authors, everything's on the website!