KnightOS was an interesting operating system

When I was a school IT admin, I saw students try a lot of creative things.<p>Some of the best, were thanks to KnightOS.<p>There are a lot of stories, but I might relate what might have to be my proudest.<p>The teacher had caught the students fooling around with BASIC to share notes, and for some reason thought that sharing notes about what they were talking about was counterproductive to the lesson, so asked me to erase the capability.<p>I didn&#x27;t want to, but orders are orders, and I could only appeal all the way up the food chain to the principal, who barely managed to use his email on his best days.<p>So as I was doing as instructed, I noticed one of the calculators that came across my desk had KnightOS. This one hadn&#x27;t been part of the note sharing, but had an interesting program on board that was still being written.<p>I called the student in excitedly, to ask them to explain, hoping I was right. I was. They were making a program that transmitted a minimal MIMEfile across the 2.5mm cable from one device to another. They were implementing email.<p>This was the first C-compiler that they&#x27;d be allowed to touch. Their parents strongly believed that girls had no place in IT, and did everything they could to keep her away from the computer at home. Her calculator with KnightOS was her only outlet.<p>When it came time to hand all the calculators back, I casually mentioned the program she wrote to one or two of the students.<p>Within the week, everyone in the class was running KnightOS and sending each other emails of notes in the class.<p>When the teacher came back and complained, I then had the power to appeal to the principal that the teacher was complaining that her students were using email, using a program that a student had built herself to send email.<p>When the principal heard that, it wasn&#x27;t note passing anymore, because he knew what email was. It went from potential punishment, to the girl who wrote an email program getting called up in assembly to be congratulated in front of everyone.<p>I didn&#x27;t really keep taps on anyone, but from what I&#x27;ve heard, that girl now works for a game development company in town.

I feel like constraints are where developers get to shine. On a system with (relative) unlimited resources, many developers seem to be able to complete the same tasks. But when there is scale involved or some constraint (like 4 mb of storage) you get to find out who is willing to learn what they need to learn to get the job done.

When I was in high school, I always wanted to build a better OS for the TI-84, but I did not have the skills or attention span to do it on my own. When KnightOS came along, I got involved and was able to take on individual features or issues as bite size chunks. I was able to make real contributions to a project that resonated with me on a fundamental level. In the process, I learned z80 assembly, how OSs work, but also most importantly how to contribute to a real open source project.<p>Thanks, Drew.

KnightOS is a system I&#x27;ve been wanting to try for years, although I don&#x27;t have the hardware for it. It&#x27;s an admirable achievement.<p>How hard would it be to get KnightOS to be able to self-host? Something like an 8080 or Z80 is probably the wimpiest processor that it makes sense to try to build a self-hosted development environment on; although there were compilers that could run on the PDP-8 (address space: 4096 12-bit words), John Cowan tells me that in practice people did most software development for the -8 on bigger machines like a PDP-10.<p>CP&#x2F;Mish is the other free-software operating system for the Z80 (and also runs on the 8080), but it&#x27;s pretty far from self-hosting. As I mentioned in Dercuano, there&#x27;s a free-software C compiler for CP&#x2F;M which can run under CP&#x2F;Mish (BDS C) but its dialect of C is not the one CP&#x2F;Mish is written in.<p>A really small bootstrapping environment like this could go a long way to making computers comprehensible and making the Karger–Thompson attack infeasible.

&gt; In fact, the “userspace” task switching GUI would read the kernel’s process table directly to make a list of running programs.<p>This is great. A perfect learning project is trying to build something yourself, then learning how other developers solved the problems or larger OSes handle it (or working backwards from that point and simplifying).<p>I noticed some &quot;#ifdef FLASH4MB&quot; in the linked source code, was it difficult to update it for 4mb or were similar constraints in place where it was basically the same with more memory?

Relevant: Ndless[1], a jailbreak for TI-Nspire calculators (Nspire {CX ,}{CAS,}). I&#x27;ve played around with the source code[2] as well as compiling Rust[3], Nim[4], and Zig[5] to target it. It&#x27;s all pretty neat, there&#x27;s a gba emulator for the TI-Nspire floating around somewhere as well.<p>[1]: <a href="https:&#x2F;&#x2F;ndless.me" rel="nofollow">https:&#x2F;&#x2F;ndless.me</a><p>[2]: <a href="https:&#x2F;&#x2F;github.com&#x2F;ndless-nspire&#x2F;Ndless" rel="nofollow">https:&#x2F;&#x2F;github.com&#x2F;ndless-nspire&#x2F;Ndless</a><p>[3]: <a href="https:&#x2F;&#x2F;github.com&#x2F;coolreader18&#x2F;rsspire" rel="nofollow">https:&#x2F;&#x2F;github.com&#x2F;coolreader18&#x2F;rsspire</a><p>[4]: <a href="https:&#x2F;&#x2F;github.com&#x2F;coolreader18&#x2F;Nim&#x2F;tree&#x2F;tinspire" rel="nofollow">https:&#x2F;&#x2F;github.com&#x2F;coolreader18&#x2F;Nim&#x2F;tree&#x2F;tinspire</a><p>[5]: <a href="https:&#x2F;&#x2F;github.com&#x2F;coolreader18&#x2F;zigspire" rel="nofollow">https:&#x2F;&#x2F;github.com&#x2F;coolreader18&#x2F;zigspire</a>

Obstacles and difficulty make us better at things. Lack of obstacles makes us complacent. This is a known phenomenon.<p><a href="https:&#x2F;&#x2F;www.ted.com&#x2F;talks&#x2F;tim_harford_how_frustration_can_make_us_more_creative" rel="nofollow">https:&#x2F;&#x2F;www.ted.com&#x2F;talks&#x2F;tim_harford_how_frustration_can_ma...</a>

Also interesting: PunixOS, a sadly-dead project to port 4.4BSD to Motorola 68k calculators like the TI-89. Not just a Unix-alike, but a Real Unix (tm), with pre-emptive multitasking and everything.<p><a href="http:&#x2F;&#x2F;punix-os.blogspot.com&#x2F;" rel="nofollow">http:&#x2F;&#x2F;punix-os.blogspot.com&#x2F;</a>

As a former small-time contributor, KnightOS was an exciting dream. From the programmer&#x27;s perspective, it got a lot of things <i>right</i> and really modernized the 6MHz environment from feeling like something designed in the 80s to something you felt like you could build a real piece of software on. I had written a computer algebra system for the 84 Plus and I was considering porting it to KnightOS because it would have gotten rid of a lot of baggage I had to do to support TI&#x27;s operating system.<p>KnightOS never had the momentum it really deserved, and the calculator hacking community was far more involved with equally impressive projects in other genres (for example, the Axe Parser was an onboard compiler for a high level language designed for writing games on the 84 Plus). Still cool to go back and play with the website.

Neat. Would be interested to see a quick video&#x2F;GIF tour.

There goes my day.

Also, Lunix (C64)

At first I confused it with Temple OS. That was also very interesting but maybe less useful

With no MMU or hardware supervisor mode, this would be more of a simple task executor than an OS in any reasonably-modern sense. Still impressive though.