Coreboot Hikes The Bay Trail To DRAM Initialization

This article is written on an open-source operating system, but not an open-source machine — the BIOS isn’t open-source, and even if it were supported by the coreboot project (formerly LinuxBIOS), there would still be a whole host of binary blobs required to get it to boot. On one vintage architecture, there’s one less blob, as coreboot can now initialize DRAM on Intel Bay Trail SOCs, as [Mate Kukri] presented in a talk at the recent Open Source Firmware Conference.

Bay Trail isn’t exactly cutting-edge hardware, to be sure — the SoCs are over a decade old at this point, and were only used in low-performance mobile applications like Chromebooks. On the other hand, coreboot has been on Chromebooks for at least as long. Getting DRAM set up is difficult because, well, you don’t have any memory to work with until you do. Traditionally, the way you did that was to call on one of the many proprietary ‘binary blobs’ provided with next to no documentation by the manufacturer. Reverse engineering that requires some serious bus-sluthing, which was done in software with the SerialICE debugger and the Unicorn Engine CPU emulator. The talk focused on that technique and how it might be applied more widely, rather than getting into the weeds of how to do DRAM init on one obsolete SOC. At some point the whole thing should be archived on the OFSC website so those of us not lucky enough to attend in person can hear what [Mate] — and all the other speakers — had to say.

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Hackaday Europe 2026: Bare Metal Made Easy

When we talk about programming in “bare metal,” it basically means writing software that runs right on the hardware with no operating system or abstraction layers in between. This gives the program the most direct possible access to peripherals and memory, with the tradeoff being that you don’t get the protection and ancillary features that come with an OS.

Sylvain Huet came down to Hackaday Europe 2026 to talk about making bare metal easy. Not just by ignoring operating systems and ever-bloating dependencies, but by rethinking the way we approach software development and by building a transparent platform from the ground up.

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If It’s Electronic Paper, Why Not Print To It?

E-ink is supposed to be the electronic version of dead-tree paper, but there’s one enormous difference: how you get your images and text onto it. For paper, you print on it. E-ink? Well, it depends on what it’s hooked up to. If it’s an ESP32C3-based Xteink X4 and X3, then you can just print to that, too, thanks to [Nishant Joshi]’s fork of the popular CrossPoint firmware.

The fork implements the Internet Printer Protocol, IPP, on the ESP32-C3. It makes loading documents a breeze: select the printer in your operating system, and press print. To the computer, the reader advertises itself as a printer that provides monochrome, single-sided output at 300 DPI on A5 paper, and accepts Apple raster and PWG raster formats. Of course these raster images are enormous compared to the paltry RAM available on the microcontroller, so pixels are received and written row-by-row — both to the screen directly, and to the SD card for later perusal. That makes a folder on the SD card the equivalent of a printer’s output tray.

This interface is amazing in its simplicity, and we’d love to see it in other E-ink devices. It reminds us somehow of AlphaSmart word processors — which are still relevant today in large part because their ‘file transfer’ mechanism is to pretend to be a USB keyboard and type the document onto your computer. As long as IPP is available, so too will you be able to get documents onto this e-reader.

Old IPad Keyboard Makes For A Modern Netbook

Netbooks were a class of tiny laptops which hit their peak over a decade ago, with the idea being that you could use the Internet and do your computing on the move with ease. Unfortunately manufacturers were scared of them eating their profits from bigger computers, and they were invariably built to a very disappointing spec. That doesn’t lessen the appeal of small form factor laptops though, and [bob-foss] is here with a simple hack to make one.

He’s taken a hinged keyboard case made for one of the previous generations of iPad Mini, and paired it with a high-end Lenovo gaming tablet by way of a 3D printed replacement for the original Apple-grabber. We said it was a simple hack and it is, but it’s no less elegant for that as the detail is what matters. This isn’t a mess-of-wires cyberdeck, instead it’s a machine you could pull out on a train and get some work done.

Meanwhile, if you’d like to take a wallow in what that netbook thing was all about, we took a look at the phenomenon back in 2020.

Repairing Traces On A Delidded Pentium III CPU Gone Wrong

Delidding a CPU involves removing the integrated heat spreader (IHS) that’s put over the bare die and the substrate that it is mounted on. The reason for this is usually to improve cooling performance, as the IHS is effectively a small heatsink between the die and the large heatsink, adding more problematic thermal interfaces. If delidding is done improperly it can cause severe damage to the substrate, as in the case of a very nice 1.3 GHz Tualatin Pentium III CPU that [Bits und Bolts] got in an eBay lot with nasty delidding damage.

With the delidding enthusiast presumably having used brute force and ignorance combined with a prying implement, around a dozen of tiny traces on the substrate got severed, requiring tedious trace repair to fix. After confirming that with the severed traces the CPU is indeed busted, enough of the soldermask is removed to make a repair.

Any traces that were still good got covered with soldermask, while for the remainders the thinnest available copper wire was used to create new traces. Although very much doable with a good microscope and a steady hand, this is definitely one of those things that’s much easier to prevent than to fix.

With IHSes having become standard on CPUs, delidding continues to this day, with increasing risks of severed traces and ripped-off capacitors should it go wrong. Although those newer CPU substrates are probably not repairable, repairing these older CPUs instead of tossing them as e-waste seems plausible at least.

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“I’m Not Dead Yet!” Reverse Polish Notation Calculators You Can Still Buy

If you used a scientific calculator in the 1970s or 1980s, there was a fair chance that it worked differently from almost every calculator you see today. Instead of typing:

2 + 3 =

you entered:

2 ENTER 3 +

There wasn’t even an equals key. Hewlett-Packard made this system — Reverse Polish Notation, or RPN — practically synonymous with serious scientific calculators until other players like TI and Casio got serious. Once you got used to it, ordinary algebraic calculators could feel annoyingly clumsy.

Today, RPN calculators look like a nearly extinct species. HP left the calculator market, licensing the HP calculator line to Moravia Consulting. Old HP-15Cs, 16Cs, 32Ss, 42Ss, and 48s have become collectibles. But RPN isn’t dead. You can still buy new hardware, build your own, or turn almost any computer or phone into a very capable RPN machine. There are reasons some of us still want to.

But Why Polish?

The name goes back to Polish logician [Jan Łukasiewicz], who devised a notation in which operators precede their operands. Instead of writing:

A + B

you can write:

+ A B

The big advantage is that parentheses aren’t required. The structure of the expression tells you exactly what operates on what. Reverse Polish notation simply puts the operator at the other end:

A B +

[Łukasiewicz] wasn’t designing calculators, of course, but the same idea turned out to be extremely convenient for computers and calculators. Your software doesn’t have to remember what operation is in progress. Each operator is ready to go and can simply work on the operands that you’ve already read.

RPN isn’t exactly the way people calculate with pencil and paper, and it certainly wasn’t derived from the slide rule, but there is a similarity in the way you work. With a slide rule, you generally establish some value, operate on it, and continue from the result. When doing a long-hand calculation, you often calculate a subexpression, write down the answer, and use that answer in the next step. You will probably start with the inner parenthesis and work outward, just like someone with an RPN calculator does. RPN formalizes that process with a stack.

Suppose you want:

(3 + 4) × (5 + 6)

On a conventional calculator, you either need parentheses, or you have to calculate one result and remember it. On an RPN calculator:

3 ENTER

4 +

5 ENTER

6 +

×

The first + leaves 7 on the stack. The second leaves 11 above it. The multiply consumes both and leaves 77.

Notice what’s missing: parentheses, an equals key, and any need to tell the calculator about precedence. This isn’t much of a win for a five-key calculation. It becomes more apparent with something like computing the value of a bunch of parallel resistors:

R=1/(1/R1+1/R2+1/R3…)

An RPN user can calculate each reciprocal, add it to the running result on the stack, and finally take the reciprocal. Intermediate answers stay in the calculator naturally instead of being stuffed into memory registers or enclosed in increasingly impressive collections of parentheses.

Is RPN better? Calculator users have been arguing about that for half a century. But once RPN gets wired into your fingers, it can be surprisingly hard to give up.

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All The Best Computers Boot To BASIC

Anyone whose first computing experience came in the form of an 8-bit home computer will tell you about booting straight into a BASIC interpreter. The machine invited you to program it, and no doubt many of our middle aged readers are here today because they ran with that.

Modern computers with their fancy 64-bit multitasking supercomputer operating systems may have lost that experience, but now thanks to [Tarjan] you can bring it back. They’ve produced Thoreau BASIC, a bootable bare-metal BASIC interpreter for x86 machines with UEFI.

It’s largely GW-BASIC compatible, but with a few upgrades for the 21st century. The available memory is now whatever the system reports, so imagine a BASIC machine with gigabytes of the stuff. And while it has all the old-style BASIC you know and love, it also has high-res 24-bit graphics, and can load bitmaps. There can even be multiple text windows, it’s BASIC as you have never seen it before.

We are not sure how many will take this interpreter and run with it, after all maybe those modern 64-bit operating systems can be rather useful at times. But we’re guessing there will be plenty who’ll at least have a play with it for old time’s sake. Meanwhile, BASIC is not the only piece of UEFI goodness we’ve brought you.