weekend = day_of_week in (“sat”, “sun”)

As a bonus this completely sidesteps the issue of what day is 0 or 1.

Well that’s an odd way of putting it ;)

Those are different kinds of fine motor skills than used when writing cursive. Ideally kids should be exposed to both.

Cursive writing helps in developing fine motor skills.

Would be interesting to figure out what causes this. Is it the bad grammar itself or some feature of our education?

Yeah, hobbit-serial architectures lack performance.

So the Fellowship of the Ring was made up of an elf, a dwarf, two humans, a maia and one hobnibble?

Oh hey, how about Madagascar?

A non-recursive recursive descent parser isn’t any easier to reason about.

I had been thinking about doing something akin to the X16 but more modern, but realised that the main challenge with launching a product like this lies not in doing the design, but in coordinating all the people that are involved in producing the hardware, software and documentation (and hype, don’t forget hype). And you’ve gotta hand it to David Murray (the 8-bit guy): he’s knows how to do this, and has demonstrated this before with Planet X3.

It’s weird in the sense that software development has moved in other directions. A tagged-architecture stack machine like the Burroughs Large System is weird as well, even though it’s been highly successful and very influential on later designs (eg. Forth, SmallTalk).

If we’d still be using bank switching and overlays I’d say learning to code assembly on a 6502 is a great introduction to modern computers, but we’re not so it’s not.

Exactly. Something in the spirit of an Amiga 500 (I never had one, so this is not nostalgia speaking) is much more suitable to beginning programmers. Something with a flat address space, an easily memorisable instruction set and rich collection of hardware (blitter, DMA controller, sound generator) to play with. And something that has modern interfaces (HDMI & USB) so the not-so-well-equipped hacker-in-training can also jump in right away.

The Commander X16 isn’t it.

There’s plenty of choices. If you want that retro vibe go for a 68k, if you want something neat but obscure (and are willing to use an FPGA) choose the pdp-11, if you want to go with the flow then use risc-v.

But please pick something that’s not actively fighting modern (that is, not 1970’s) programming techniques.

People would learn bad habits.

For example, due to parameter passing often being done via the zero page, recursion is unnecessarily hard on the 6502, whereas one could argue that recursion is one of the major skills to master for any programmer.

The 6502 was weird back in the day as well, just weird in an ubiquitous way. It’s registers are too small, it’s stack is too small, it’s address space is too small. Argument passing often had to be done using the zero page, and since none of its registers can hold a respectable portion of its address space it requires hacks to implement such obscurities as C-style pointers. No current ABI can trace its origin to the 6502 (not even ARM).

Sure, back in the day the alternatives at the price point were worse, but that doesn’t make the 6502 good.

If you want a good CPU design with a 16-bit address space, take a look at the PDP-11.

Though I really like the concept of building a new device which incorporates the inherent ease of programmability of the computers of yore, I think the 6502 is just too weird and limited for doing so. For example, in order to cram a halfway decent amount of memory into the thing they had to resort to bank switching. At the least they should’ve gone with a 65816 (apparently they tried but they initially had some problems with the '816 address bus multiplexing).

“Clearly these numbers have a ritual purpose”

Kinda looks like an impedance mismatch.

Secondly at least AC alternates, giving your muscles a break and possibly a chance to let go of the wire, DC isn’t that forgiving.

Interesting. Your comment made me read up on all of this. Note that, since V_rms = 1 ÷ √2 × V_peak, 230VAC has a V_peak of 325V, so in that respect, it should be pretty much equivalent to 300VDC. I figured that the ability for AC to induce heart fibrillations was the most dangerous factor in all of this, but I hadn’t figured in that DC induces tetanus and can also temporarily stop the heart.

It’s not the volts that kill you though, it’s the amps (the volts just make it easier). I found a table listing the effects of various amperages. It does present DC as generally more safe when compared against 60Hz AC, but I’m not sure how that generalises to the 50Hz AC we have here. I do conclude however that I should be limiting the output current to something something generally safe, like 20mA (which should be fine for a voltage reference). I’m thinking a PTC at the input and being conservative wrt capacitor sizing should do it.

Some of my co-students in university made an EKG apparatus. Our lecturer demanded that anything connected to the electrodes was to be powered by a single battery.

TBH, when it comes to an EKG apparatus I’d also be worried about common mode across the chest, or the power supply having a disastrous failure mode.

I prefer my Sn60Pb40 (…) The first couple of lead free solder brands I got just didn’t flow right.

Yeah, those were horrid. Even the supposedly excellent SAC305 gave me dull joints (tough it flowed adequately). Still, I can only recommend Sn100Ni+ (supposedly closely related to SN100C): flows well and gives me the shiny joints I crave. Having a good soldering iron (I’m using a Pinecil) helps with solderability.

I do however still have some rosin core Sn60Pb40 for reworking vintage electronics. And I do agree that it’s just better when it comes to wetting ability. The peace of mind when working with lead-free solder really is worth it though, especially with pets or small children.

my anxiety level is exponentially correlated to the working DC voltage and at 300VDC I’m definitely well in the thick rubbergloves territory.

Having been walloped by 230VAC, which is far more dangerous, I’m not too worried.

Looking at the schematic you linked above, the amperage is going to be low, which is reassuring. As a safety measure, I’m looking into running the thing off of a battery, so that if the worst comes to pass it simply won’t have the power to be dangerous (1A at 12V translates to a mere 40mA at 300V).

I’d be far more worried about using lead solder TBH (love my Sn100Ni+).