Notes on the Pentium's microcode circuitry

Most people think of machine instructions as the fundamental steps that a computer performs. However, many processors have another layer of software underneath: microcode. With microcode, instead of building the processor's control circuitry from complex logic gates, the control logic is implemented with code known as microcode, stored in the microcode ROM. To execute a machine instruction, the computer internally executes several simpler micro-instructions, specified by the microcode. In this post, I examine the microcode ROM in the original Pentium, looking at the low-level circuitry.

The photo below shows the Pentium's thumbnail-sized silicon die under a microscope. I've labeled the main functional blocks. The microcode ROM is highlighted...

Link – Rendering light-trail geometries

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Link is a series of 28 generative stop-motion loops, with each sequence comprising between 32 and 224 individual long-exposure photographs. Each frame of the sequence is obtained through a long-exposure capture (~30 seconds) of a vertical LED array in motion, resulting in precise, three-dimensional light-trail geometries.

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Name that Ware, March 2025

The Ware for March 2025 is shown below.

I was just taking this thing apart to see what went wrong, and thought it had some merit as a name that ware. But perhaps more interestingly, I was also experimenting with my cross-polarized imaging setup.

This is a technique a friend of mine told me about where you put a polarizer on the light source, and then put another polarizer 90 degrees from the light source in front of your imaging lens. As you can see from the comparison above, the contrast on the part numbers is greatly enhanced — at the expense...

Winner, Name that Ware February 2025

The Ware from last month is the main board from a Lego Duplo Steam Train. As predicted, this was a much easier one to guess. Congrats to MJS for naming it (with a margin of just half an hour ahead of Will), email me for your prize! And again, thanks to spida for contributing yet another ware.

DIY PTP Grandmaster Clock with a Raspberry Pi

DIY PTP Grandmaster Clock with a Raspberry Pi

tl;dr: I set up an open source Time Pi project to build a stratum 1 PTP and NTP timeserver using a Raspberry Pi.

Time is important to modern society, and most of us have a clock on our wrist that's more accurate than at any time in human history. But highly precise time is important in many industries, especially robotics, finance, and media production. And with tech like VR working its way into homes, precise time may become more important...

Ghetto soldering tweezers

[Misc] And other 3D printed accessories

Never in a million years...

Never in a million years...

...would I have imagined my video on whether a pigeon is faster than the Internet would end up on a popular Italian quiz show, L'Eredita. Specifically, in the March 26th episode (playable in Italy, or with an account).

The question, roughly translated:

A test by the expert Jeff Geerling from 2023 proved that in transporting data the carrier pigeons can be more, what?

TinyCard Game Maker [Updated]

TinyCard is a simple text game maker to allow children to create short adventure games, interactive stories, surveys, or quizzes:

The TinyCard text game maker based on a 160x128 colour TFT display
and an ATtiny3224.

It's based on a low-cost TFT display controlled by an ATtiny3224 microprocessor. It includes four coloured buttons for interacting with the games, and there's an interface to a keyboard for entering and editing text. An optional SD card socket lets you save and load games, or give them to friends to play. The whole circuit is powered by two AAA batteries, and they act as a convenient angled...

I won't connect my dishwasher to your stupid cloud

I won't connect my dishwasher to your stupid cloud

This weekend I had to buy a new dishwasher because our old GE died.

I bought a Bosch 500 series because that's what Consumer Reports recommended, and more importantly, I could find one in stock.

After my dad and I got it installed, I went to run a rinse cycle, only to find that that, along with features like delayed start and eco mode, require an app.

Samsung / Hanwa SMT pick and place machines consumables are in stock

We operate eight such machines at Olimex and there are lot of parts which are consumables, so we keep some items always in stock to be sure there will be no accidental production stops. For instance the nozzles are wearing and need to be replaced on every 6-8 months as with the time after millions […]