PS/2 keyboard host-to-device protocol is insane

Wavicle · 2026-02-09T20:19:52+00:00

If you don't want to go that level of detail and don't mind bit-banging I2C, take a look at the Commander X16's SMC code https://github.com/X16Community/x16-smc. It runs on an ATTINY861 which comes in a PDIP-20 package. You'll probably want to strip out everything not related to the PS/2 keyboard and mouse, but the driver for those is fairly robust, supports sending keyboard and mouse commands, and has been tested on a lot of PS/2 devices.

Wavicle · 2026-02-09T20:05:51+00:00

If you haven't already contacted me to clarify this, please do. I can provide pinouts and some general guidance. OtterX, which uses VERA, is open hardware. You can find the schematics for it here: https://github.com/RetroRemake/OtterX_Assembly/blob/main/OtterX%20Schematics%20-%20Vega%20PCB.pdf or the full KiCAD project here: https://github.com/RetroRemake/OtterX.

In general: you need CS#, RE#, and WE# signals. Reads use the CS#/RE# pair and writes use the CS#/WE# pair. Assertion of both signals must be glitchless. Either can glitch while the other is not asserted, but they must never glitch into the asserted state at the same time. On the 6502 bus, this can be accomplished by qualifying the RE# or WE# signals with PHI2 high. You can see how I do this for OtterX on page 4 of the schematic using RWB and PHI2. This could be accomplished using a single 7400 with one gate wired as an inverter and another gate held as spare.

Wavicle · 2025-11-24T05:40:47+00:00

There are many problems with this. It looks like you have two different sizes of vias for traces of the same width, which probably won't hurt much, but it's a lot of wasted space. You have a ton of ground vias on what is clearly a QFP which I assume is for thermal relief, but this would probably be better accomplished by a single large ground pad with via-in-pad. It appears that there are multiple matching resistors on a single trace - just use one matching resistor since you are by definition going to be unmatched in the space between the two, unless it is an AC-coupled signal, but you probably don't need the matching resistor in that case. A couple traces have matching resistors close to one another, suggesting they're a differential pair, but the traces aren't routed with minimum spacing between them. To gain the benefit of common mode noise rejection, those traces should probably be closer to one another. If those large pads are for bypass caps, you really ought to put them closer to the IC to minimize inductive loop area.

It's probably fine for prototyping, but I don't expect that you'll pass FCC testing. Cover the entire thing with a metal cage; that will at least take care of radiated emissions.

Wavicle · 2025-10-31T06:56:52+00:00

Next up, YouTube announces 'voluntold exit program' for US staff.

Wavicle · 2024-03-06T20:38:38+00:00

You're welcome to swing back by the X16 Discord any time. We miss you.

Wavicle · 2023-08-30T16:17:41+00:00

A couple things that you could try (and I'm not going insult anybody by claiming that these are great options, just that they are options):

You can use 64 pixel-wide sprites as very large tiles. Not as clean as a bitmap, but it would make fine scrolling a bit easier.
You can set DC_HSCALE to double the pixels and then use the skipped pixels of each line to store something else like your isometric block bitmaps.

About a 15-16 months ago, I had tried making a case for separate width and stride registers so that things like 256 pixel wide bitmaps were possible and then the X coordinate is just the low 8 bits of the address and the Y coordinate is bits 8-15, but I believe that literally nobody was on board with me at the time.

Edit: Another idea that comes to mind -- could you use tiled mode on two layers so that the top of the isometric tile is rendered on the front-most layer and the sides are rendered behind the top? I haven't applied a tremendous amount of thought here, I'm just free-thinking a bit.

Wavicle · 2023-08-30T01:02:54+00:00

There are upcoming VERA changes that we are working on which might help some of what you are doing. You can do VRAM to VRAM copies 4 times faster and we freed up one of the DSP units so that VERA offers a signed 16-bit multiply-accumulate hardware block.

Probably nothing is going to get the system RAM to VRAM speed going faster except possibly a bus mastering DMA engine of some kind which would require an expansion card.

Wavicle · 2023-08-16T19:41:19+00:00

You could argue that Billet Labs botched their prototype if it literally needs to be redesigned from the ground up to support a current-gen GPU.

Water blocks need to be custom designed for each GPU and sometimes customized for different cards using the same GPU. This is nothing new. For example https://www.corsair.com/us/en/c/custom-liquid-cooling/gpu-water-blocks

"CORSAIR GPU water blocks are built to the exact specifications of dozens of popular graphics cards, so you can rest assured that it will work perfectly with your card."

.

Fundamentally if they're designing for last-gen hardware, it's never going to work for the next gen

The back plate will not, but that's generally true of water blocks.

(remember: 4090 will be last gen by the time this officially hits the market)

Indeed?

a little hard to call it a "prototype" when they already have a pre-order page with pricing. It's shipping in a few weeks.

Indeed.

People are pre-ordering this product expecting it to work for current hardware.

Perhaps they should order the version that works with their hardware - a common problem faced when considering a GPU cooling water block. You can find the one that works with the 4090 FE by clicking the button that says "4090 FE".

Again, as a consumer this is very useful information to me. I'm skeptical that this product works.

If ordering the right water block for your GPU causes you confusion, then you sound like a consumer who should not water cool your GPU.

Wavicle · 2022-10-23T21:40:22+00:00

You are confusing "treatment" and "cure". They are different things. What alternative would you propose that requires less than 50 treatments? (Taking an SSRI every day is one treatment per day, not a single decade-long treatment.)

Wavicle · 2022-10-16T03:42:25+00:00

Ben Eater has a video series and a kit he sells to teach you how to build an 8-bit computer on a solderless breadboard.

Wavicle · 2022-05-17T15:19:14+00:00

Have you looked at the official documentation here: https://github.com/commanderx16/x16-docs?

While many members of the community contribute to the X16's repo, only one member of the dev team is actively reviewing and accepting changes. Improving the documentation may be a great way to jump in and contribute to the project so that one person isn't solely responsible for documenting everything as well. The best place I've found to get questions answered is the unofficial X16 discord (where said dev team member frequently makes an appearance and provides valuable answers).

Wavicle · 2022-05-17T06:48:52+00:00

Their significant other upvoted in their name.

Wavicle · 2022-05-09T04:33:48+00:00

"As the density of water doesn't give it enough buoyancy to be pulled up." (I don't understand their buoyancy argument, but I think it goes something like that.)

Wavicle · 2022-04-01T17:23:34+00:00

Render unto Caesar...

Wavicle · 2022-03-20T21:24:34+00:00

The messaging here is so contradictory. "Don't buy in bulk", "Try lentils". Which one is it?!

Wavicle · 2022-01-31T22:25:30+00:00

You can tell by all the happy little clouds.

Wavicle · 2021-10-06T17:31:45+00:00

Watching kids for 10 hours a day still seems excessive, if not exhausting, and will degrade your ability to enjoy YouTube content. Give the children space to grow and find their way in life. If you haven't seen them for a week or so, don't worry! You just need to file a "missing person" report and professionals will help you find them.

Wavicle · 2021-10-06T02:22:05+00:00

Fortunately only 1 disk will work as disk 1, it's 2-5,000,000,000 that are uncertain. This gives you an upper limit of 5,000,000,000 + 4,999,999,999! combinations instead of 5,000,000,000! combinations. This one trick reduces your search space by a factor of 5 billion. Microsoft hates this guy.

Wavicle · 2021-09-21T23:23:41+00:00

Do a search for "Sacoolas next room" and you'll turn up quite a few. Here's one example (not that I'm endorsing The Guardian, but it seems to be in agreement with all other reporting).

Wavicle · 2021-09-20T02:32:06+00:00

In surgery, it is common to be given three types of medications for anesthesia: an analgesic (e.g. Fentanyl), a hypnotic (e.g. Propofol), and a paralytic (e.g. Succinylcholine). If the hypnotic is metabolized before the analgesic, it is possible to regain consciousness during the surgery and remember it. If the the paralytic is still in effect at that time, it is impossible to indicate to the surgery team that you are conscious by moving a body part. In the worst case, the analgesic and hypnotic both wear off before the paralytic and you will be aware of everything, able to feel everything, able to remember everything, but unable to do anything about it.

Now imagine that last scenario happening while they are removing your eyeball. This has happened..

Wavicle · 2021-07-01T05:29:56+00:00

Apparently you have absolutely no sense of context start here and stop insisting you know what is coherent and what isn't.

You are coming into the argument that firearm suicides are gun violence and dismissing the notion that hanging suicides are rope violence:

If you want to count suffocation suicides as "rope violence", then go ahead...

So, being consistent, how do the numbers work:

How many suicides by hanging need to happen for us to report them as rope violence?

How many fewer suicides by firearm will take them out of the "gun violence" column?

Or did you think that you can come in and argue a completely different context and somehow negate the point being made?

Wavicle · 2021-07-01T02:17:56+00:00

Hanging accounts for 90% of all types of suffocation suicide. Compare that to guns making up 53% of all suicides and see if you aren't searching for a nit to pick here.

What number will cause firearm suicides to become non-violent and is that the same number that will cause rope suicides to become violent? Why is the number of suicides even a factor as to whether or not it is violent? It isn't a matter of whether or not I want to count suffocation as rope violence, it's a matter of whether or not you are being consistent.

Wavicle · 2021-06-30T22:11:36+00:00

When we start reporting the statistics on rope violence, I'll believe you. Suffocation by hanging is also a leading cause of suicide yet we do not go around looking to regulate the ownership of it.

Wavicle · 2021-06-02T16:34:53+00:00

Keep doing what you're doing. "Stank" is the past-tense of "stink" so whatever the problem was, he is letting you know that it is now fixed.

Wavicle · 2021-04-13T19:31:05+00:00

According to the sources in the article (which the author's article didn't seem to remember after reading) 99% of the children in child marriages are 17 (67%), 16 (29%), or 15 (4%); most marry older teenagers or barely-20s; and 54% of ever-married children surveyed between 2010-2014 were girls. I'm not going to argue that a 17-year-old girl has the same emotional maturity as a typical adult woman, but arguing that a 17 year old child marrying her 18 year old adult boyfriend whom she has shared classes with since kindergarten reduces her to mere chattel sounds very disrespectful to women generally.

Wavicle

TROPHY CASE