Moondream title with man's face visible in background.

Using Moondream AI To Make Your Pi “See” Like A Human

[Jaryd] from Core Electronics shows us human-like computer vision with Moondream on the Pi 5.

Using the Moondream visual language model, which runs directly on your Raspberry Pi, and not in the cloud, you can answer questions such as “are the clothes on the line?”, “is there a package on the porch?”, “did I leave the fridge open?”, or “is the dog on the bed?” [Jaryd] compares Moondream to an alternative visual AI system, You Only Look Once (YOLO).

Processing a question with Moondream on your Pi can take anywhere from just a few moments to 90 seconds, depending on the model used and the nature of the question. Moondream comes in two varieties, based on size, one is two billion parameters and the other five hundred million parameters. The larger model is more capable and more accurate, but it has a longer processing time — the fastest possible response time coming in at about 22 to 25 seconds. The smaller model is faster, about 8 to 10 seconds, but as you might expect its results are not as good. Indeed, [Jaryd] says the answers can be infuriatingly bad.

In the write-up, [Jaryd] runs you through how to use Moonbeam on your Pi 5 and the video (embedded below) shows it in action. Fair warning though, Moondream is quite RAM intensive so you will need at least 8 GB of memory in your Pi if you want to play along.

If you’re interested in machine vision you might also like to check out Machine Vision Automates Trainspotting With Unique Full-Length Portraits.

Continue reading “Using Moondream AI To Make Your Pi “See” Like A Human”

Photo of the Haasoscope Pro

Haasoscope Pro: Open-Everything 2 GHz USB Oscilloscope

Our hacker [haas] is at it again with the Haasoscope Pro, a full redesign of the original Haasoscope, which was a successful Crowd Supply campaign back in 2018.

This new Pro version was funded on Crowd Supply in April this year and increases the bandwidth from 60 MHz to 2 GHz, the vertical resolution from 8 to 12 bits, and the sample rate from 125 MS/s to 3.2 GS/s. Selling for $999 it claims to be the first open-everything, affordable, high-bandwidth, real-time sampling USB oscilloscope.

The firmware and software are under active development and a new version was released yesterday.

Continue reading “Haasoscope Pro: Open-Everything 2 GHz USB Oscilloscope”

A photo of the internal wiring.

Imagining The CPS-1: An Early 70s 4-bit Microcomputer From Canada

[Michael Gardi] wrote in to let us know about his project: CPS-1: Imagining An Early 70s 4-bit Microcomputer.

The CPS-1 was the first Canadian microprocessor-based computer. It was built by Microsystems International Ltd. (MIL) in Ottawa between 1972 and 1973 and it is unknown how many were made and in what configurations. The CPS-1 supported a 12-bit address bus and a 4-bit data bus. MIL also developed the supporting hardware including RAM. The processor was called the MIL 7114.

[Michael] worked in collaboration with [Zbigniew Stachniak] from York University Computer Museum. [Zbigniew] had developed a MIL CPS-1 Emulator and [Michael]’s job was to implement a front panel hardware interface for the emulator which runs on a Raspberry Pi. The only complication: there are no remaining CPS-1 computers, and no known photographs, so no one can say for sure what a real front panel might have looked like!

With a bit of guess work and 3D printing, as well as some inspiration from contemporaneous hardware such as the DEC PDP-11, [Michael] came up with an implementation. He used an IO extender HAT which adds 32 IO pins to the existing Pi GPIO pins that are accessible via an 3-wire I2C interface. This was enough hardware to support the 26 switches and 29 LEDs on the panel. There’s a brief demo of the custom printed switches in the video embedded below.

If you’re interested in old school 4-bit tech you might also like to check out 4-bit Single Board Computer Based On The Intel 4004 Microprocessor.

Continue reading “Imagining The CPS-1: An Early 70s 4-bit Microcomputer From Canada”

Photo of Microtronic 2090

The Microtronic Phoenix Computer System

A team of hackers, [Jason T. Jacques], [Decle], and [Michael A. Wessel], have collaborated to deliver the Microtronic Phoenix Computer System.

In 1981 the Busch 2090 Microtronic Computer System was released. It had a 4-bit Texas Instruments TMS1600 microcontroller, ran at 500 kHz, and had 576 bytes of RAM and 4,096 bytes of ROM. The Microtronic Phoenix computer system is a Microtronic emulator. It can run the original firmware from 1981.

Between them the team members developed the firmware ROM dumping technology, created a TMS1xxx disassembler and emulator, prototyped the hardware, developed an Arduino-based re-implementation of the Microtronic, designed the PCB, and integrated the software.

Unlike previous hardware emulators, the Phoenix emulator is the first emulator that is not only a re-implementation of the Microtronic, but actually runs the original TMS1600 firmware. This wasn’t possible until the team could successfully dump the original ROM, an activity that proved challenging, but they got there in the end! If you’re interested in the gory technical details those are here: Disassembling the Microtronic 2090, and here: Microtronic Firmware ROM Archaeology. Continue reading “The Microtronic Phoenix Computer System”

The schematic on the left and the assembled circuit on the right.

How To Make A Simple MOSFET Tester

Over on YouTube our hacker [VIP Love Secretary] shows us how to make a simple MOSFET tester.

This is a really neat, useful, elegant, and simple hack, but the video is kind of terrible. We found that the voice-over constantly saying “right?” and “look!” seriously drove us to distraction. But this is a circuit which you should know about so maybe do what we did and watch the video with subtitles on and audio off.

To use this circuit you install the MOSFET you want to test and then press with your finger the spare leg of each of two diodes; in the final build there are some metal touch pads attached to the diodes to facilitate this. One diode will turn the MOSFET off, the other diode will turn the MOSFET on, and the LED will show you which is which.

Continue reading “How To Make A Simple MOSFET Tester”

What Is The Fourier Transform?

Over at Quanta Magazine [Shalma Wegsman] asks What Is the Fourier Transform?

[Shalma] begins by telling you a little about Joseph Fourier, the French mathematician with an interest in heat propagation who founded the field of harmonic analysis in the early 1800s.

Fourier’s basic insight was that you can represent everything as a sum of very basic oscillations, where the basic oscillations are sine or cosine functions with certain parameters. [Shalma] explains that the biology of our ear can do a similar thing by picking the various notes out from a tune which is heard, but mathematicians and programmers work without the benefit of evolved resonant hairs and bone, they work with math and code.

[Shalma] explains how frequency components can be discovered by trial and error, multiplying candidate frequencies with the original function to see if there are large peaks, indicating the frequency is a component, or if the variations average to zero, indicating the frequency is not a component. [Shalma] tells how even square waves can be modeled with an infinite set of frequencies known as the Fourier series.

Taking a look at higher-dimensional problems [Shalma] mentions how Fourier transforms can be used for graphical compression by dropping the high frequency detail which our eyes can barely perceive anyway. [Shalma] gives us a fascinating look at the 64 graphical building blocks which can be combined to create any possible 8×8 image.

[Shalma] then mentions James Cooley and John Tukey and the development of the Fast Fourier Transform in the 1960s. This mathematical tool has been employed to study the tides, to detect gravitational waves, to develop radar and magnetic resonance imaging, and to support signal processing and data compression. Even quantum mechanics finds use for harmonic analysis, and [Shalma] explains how it relates to the uncertainty principle. The Fourier transform has spread through pure mathematics and into number theory, too.

[Shalma] closes with a quote from Charles Fefferman: “If people didn’t know about the Fourier transform, I don’t know what percent of math would then disappear, but it would be a big percent.”

If you’re interested in the Fourier transform and want to dive deeper we would encourage you to read The Fastest Fourier Transform In The West and Even Faster Fourier Transforms On The Raspbery Pi Zero.

Header image: Joseph Fourier, Attributed to Pierre-Claude Gautherot, Public domain.

Inside and outside the Contrib Cal.

Reify Your GitHub Commit History With Contrib Cal

Over on Instructables, [Logan Fouts] shows us the Contrib Cal GitHub desk gadget. This build will allow you to sport your recent GitHub commit activity on your wall or desk with an attractive diffuse light display backed by a 7×4 matrix of multicolor LEDs. Motivate yourself and impress your peers!

This humble project is at the same time multifaceted. You will build a case with 3D printing, make a diffuse screen by gluing and cutting, design a LED matrix PCB using KiCad, solder everything together, and then program it all with Python. The brains of the operation are a Raspberry Pi Zero W.

The Instructables article will run you through the required supplies, help you to print the case, explain how to solder the LEDs, tell how to install the heat-set inserts for high quality screw attachments, explain wiring and power, tell you about how to use the various screws, then tell you about where to get more info and the required software on GitHub: Contrib Cal v2.

Of course this diffuse LED matrix is only one way to display your GitHub progress, you can also Track Your GitHub Activity With This E-Ink Display.