Author: Bryan Cockfield

1783 Articles

Misleading GPS, Philosophy Of Maps, And You

September 10, 2024 by 19 Comments

The oft-quoted saying “all models are wrong, but some are useful” is a tounge-in-cheek way of saying that at some level, tools we use to predict how the world behaves will differ from reality in some measurable way. This goes well beyond the statistics classroom it is most often quoted in, too, and is especially apparent to anyone who has used a GPS mapping device of any sort. While we might think that our technological age can save us from the approximations of maps and models, there are a number of limitations with this technology that appear in sometimes surprising ways. [Kyle] has an interesting writeup about how maps can be wrong yet still be incredibly useful especially in the modern GPS-enabled world. Continue reading “Misleading GPS, Philosophy Of Maps, And You” →

Mobile Coffee Table Uses Legs To Get Around

September 10, 2024 by 22 Comments

For getting around on most surfaces, it’s hard to beat the utility of the wheel. Versatile, inexpensive, and able to be made from a wide array of materials has led to this being a cornerstone technology for the past ten thousand years or so. But with that much history it can seem a little bit played out. To change up the locomotion game, you might want to consider using robotic legs instead. That’s what [Giliam] designed into this mobile coffee table which uses custom linkages to move its legs and get itself from place to place around the living room.

Continue reading “Mobile Coffee Table Uses Legs To Get Around” →

Rescuing High-Res Displays From Older Macs

September 10, 2024 by 25 Comments

When Apple started rolling out its Retina displays, it multiplied the amount of pixels compared to their standard, non-Retina displays by four. This increased pixel density while keeping the standard screen size — idea for those needing a lot of detail for their work. But, as is common with Apple, using these displays outside of the Apple ecosystem can be quite a challenge. Retina displays have been around for about a decade now, though, with some third-party hardware able to break them free of their cage. This post details how [Kevin] liberated the 5K display from a 2017 iMac for more general use with support for USB-C.

The first step was to find a used iMac for the right price, and then sell off most of its parts to recoup most of the initial cost. That brought the cost of the panel itself to about $250. The key to getting the display working without all of the Apple hardware is the R1811 driver board, which can be had for around $300. A new 156 watt power supply was added to the mix, and [Kevin] also put in a few extras like a USB cable extension and a latching push-button which kills the display’s power. Additionally, he attempted to get the original iMac speakers working with this setup too, but none of his attempts resulted in anything close to quality sound so he’s mostly abandoned that extra feature for now.

With that all buttoned up, he has a 27″ 5K display with USB-C input for around $650 which is quite a deal. The MacRumors thread that [Kevin] added his project to currently has around 1,700 posts about similar builds too, so it can be a wealth of information for all kinds of models. As Apple drops support for their older machines, these displays will become more and more common and projects like these can keep a lot of e-waste out of the landfill while also providing decent hardware at a bargain price. Don’t just look for iMacs and MacBooks though; there’s a similar process to use various iPad displays for other things as well.

Large Language Models On Small Computers

September 7, 2024 by 6 Comments

As technology progresses, we generally expect processing capabilities to scale up. Every year, we get more processor power, faster speeds, greater memory, and lower cost. However, we can also use improvements in software to get things running on what might otherwise be considered inadequate hardware. Taking this to the extreme, while large language models (LLMs) like GPT are running out of data to train on and having difficulty scaling up, [DaveBben] is experimenting with scaling down instead, running an LLM on the smallest computer that could reasonably run one.

Of course, some concessions have to be made to get an LLM running on underpowered hardware. In this case, the computer of choice is an ESP32, so the dataset was reduced from the trillions of parameters of something like GPT-4 or even hundreds of billions for GPT-3 down to only 260,000. The dataset comes from the tinyllamas checkpoint, and llama.2c is the implementation that [DaveBben] chose for this setup, as it can be streamlined to run a bit better on something like the ESP32. The specific model is the ESP32-S3FH4R2, which was chosen for its large amount of RAM compared to other versions since even this small model needs a minimum of 1 MB to run. It also has two cores, which will both work as hard as possible under (relatively) heavy loads like these, and the clock speed of the CPU can be maxed out at around 240 MHz.

Admittedly, [DaveBben] is mostly doing this just to see if it can be done since even the most powerful of ESP32 processors won’t be able to do much useful work with a large language model. It does turn out to be possible, though, and somewhat impressive, considering the ESP32 has about as much processing capability as a 486 or maybe an early Pentium chip, to put things in perspective. If you’re willing to devote a few more resources to an LLM, though, you can self-host it and use it in much the same way as an online model such as ChatGPT.

It’s Spreadsheets All The Way Down For This 80s Handheld

September 5, 2024 by 9 Comments

Unlike the today’s consumer computer market, the 1980s were the wild west in comparison. There were all kinds of different, incompatible operating systems, hardware, and programs, all competing against one another, and with essentially no networking to tie everything together. Some of these products were incredibly niche as well, only running one program or having a limited use case to keep costs down. Such was the Convergent WorkSlate, a computer that ran only a spreadsheet with any programs also needing to be built into a spreadsheet.

Upon booting the device, the user is presented with a fairly recognizable blank spreadsheet, albeit with a now-dated LCD display (lacking a backlight) and a bespoke keyboard and cursor that wouldn’t have allowed for easy touch typing. The spreadsheet itself is quite usable though, complete with formatting tools and the capability to use formulas like a modern spreadsheet program would. It also hosted a tape deck for audio and data storage, a modem for communicating with other devices, and an optional plotter-style printer. The modem port is how [Old VCR] eventually interfaces with the machine, although as one can imagine is quite a task for a piece of small-batch technology from the 80s like this. After learning how to send and receive information, a small game is programmed into the machine and then a Gopher interface is built to give the device limited Internet connectivity.

The investigation that [Old VCR] goes into on this project to get this obsolete yet unique piece of hardware running and programmed to do other tasks is impressive, and worth taking a look at especially because spreadsheets like this aren’t Turing-complete, leading to a few interesting phenomenon that most of us wouldn’t come across in the modern computing world. Since only around 60,000 units were ever made it’s difficult to come across these machines, but if you want to take a look at the spreadsheet world of the 80s without original hardware you can still run Lotus 1-2-3 natively in Linux today.

Thanks to [Cameron] for the tip!

A Clean Linux Installation For An Android TV Box

September 3, 2024 by 21 Comments

Although Android technically runs on top of Linux, generally most Android devices abstract away the underlying Linux-ness of these machines. In theory this is a good thing; we wouldn’t necessarily want to live in a world where we have to log in to a command-line interface just to make a phone call. But too much abstraction often needlessly restricts the capabilities of the underlying hardware. [Murray] a.k.a [Green Bug-Eyed Monster] has an Android TV box with just such a problem, as the Android OS included with it allows for watching TV just fine, but with a few tweaks it can run a full Linux installation instead, turning it into a much more versatile machine.

This specific Android TV box is based on the Rockchip 3566, a popular single-board computer used in a wide array of products. As such it is one of the easier targets for transforming a limited TV machine into a fully capable desktop computer. The first step is to compile an Armbian image for the machine, in this case using an x86 installation of Ubuntu to cross-compile for the ARM-based machine. With a viable image in hand, there’s an option to either solder on a microSD slot to the included pins on the computer’s PCB or to flash the image directly to the on-board eMMC storage by tricking the machine into thinking that the eMMC is missing. Either option will bring you into a full-fledged Linux environment, with just a few configuration steps to take to get it running like any other computer.

[Murray] began this process as an alternative to paying the inflated prices of Raspberry Pis over the past few years, and for anyone in a similar predicament any computer with the Rockchip 3566 processor in it could be a potential target for a project like this. You might need to make a few tweaks to the compile options and hardware, but overall the process should be similar. And if you don’t have an RK3566, don’t fret too much. We’ve seen plenty of other Android TV boxes turned into similar devices like this one which runs RetroPie instead.

Universal Power Bank Customized To Your Liking

August 31, 2024 by 10 Comments

One of the most troubling trends of almost every modern consumer product that uses electricity is that the software that controls the product is likely to be proprietary and closed-source, which could be doing (or not doing) any number of things that its owner has no control over. Whether it’s a computer, kitchen appliance, or even a device that handles the electricity directly, it’s fairly rare to find something with software that’s open and customizable. That’s why [Traditional-Code9728] is working on a power bank with an open-source firmware.

From a hardware perspective the power bank is fairly open as well, with a number of options for connecting this device to anything else that might need power. It sports a bidirectional USB-C port as well as a DC barrel plug, either of which can either charge other devices or receive energy to charge its own battery. These ports can also accept energy from a solar panel and have MPPT built in. There’s also dual USB-A ports which can provide anywhere from five to 12 volts at 25 watts, and a color screen which shows the current status of the device.

While this is a prototype device, it’s still actively being worked on. Some future planned upgrades to the power bank include a slimmer design, charge limiting features to improve battery life, and more fine-tuned control of the output voltage and current on the USB-C port. With all of the software being open-source, as well as the circuit diagram and 3D printing files, it could find itself in plenty of applications as well. This power bank also stays under the energy limits for flying on most commercial airlines as well, but if you don’t plan on taking your power bank on an airplane then you might want to try out this 2000-watt monster instead.