Illustrated Kristina with an IBM Model M keyboard floating between her hands.

Keebin’ With Kristina: The One With The Curvy Centerfold

What do you get when you combine a Raspberry Pi 4B, a Kaypro keyboard, and a 9″ Apple ], you get the coolest AVR development workstation I’ve seen in a while.

A Raspberry Pi-based AVR workstation that uses a Kaypro keyboard and 9" monochrome Apple ][c display.
Image by [John Anderson] via Hackaday.IO
As you may have guessed, I really dig the looks of this thing. The paint job on the display is great, but the stripes on the keyboard and badging on are on another level. Be sure to check out the entire gallery on this one.

About that keyboard — [John] started this project with two incomplete keyboards that each had a couple of broken switches. Since the two keyboards were compliments of each other parts-wise, they made a great pair, and [John] only had to swap out three switches to get it up and clacking.

In order to make it work with the Pi, [John] wrote a user-mode serial driver that uses the uinput kernel module to inject key events to the kernel. But he didn’t stop there.

Although the Pi supports composite video out, the OS doesn’t provide any way to turn off the chroma color signal that’s modulated on top of the basic monochrome NTSC signal, which makes the picture look terrible. To fix that, he wrote a command-line app that sets up the video controller to properly display a monochrome NTSC signal. Happy AVRing on your amazing setup, [John]! Continue reading “Keebin’ With Kristina: The One With The Curvy Centerfold”

Building The Spectacular Fibonacci128 Simple Add-On

This year, we not only challenged Supercon attendees to come up with their own Simple Add-Ons (SAOs) for the badge, but to push the envelope on how the modular bits of flair work. Historically, most SAOs were little more than artistically arranged LEDs, but we wanted to see what folks could do if they embraced the largely unused I2C capability of the spec.

[Squidgeefish] clearly understood the assignment. This first-time attendee arrived in Pasadena with an SAO that was hard to miss…literally. Looking directly at the shockingly bright 128 RGB LED array packed onto the one-inch diameter PCB was an experience that would stay with you for quite some time (ask us how we know). With the “artistically arranged LEDs” aspect of the nominal SAO handled nicely, the extra work was put into the design so that the CPU could control the LED array via simple I2C commands.

Continue reading “Building The Spectacular Fibonacci128 Simple Add-On”

Single Crystal Electrode Lithium Ion Batteries Last A Long Time

Researchers have been testing a new type of lithium ion battery that uses single-crystal electrodes. Over several years, they’ve found that the technology could keep 80% of its capacity after 20,000 charge and discharge cycles. For reference, a conventional cell reaches 80% after about 2,400 cycles.

The researchers say that the number of cycles would be equivalent to driving about 8 million kilometers in an electric vehicle. This is within striking distance of having the battery last longer than the other parts of the vehicle. The researchers employed synchrotron x-ray diffraction to study the wear on the electrodes. One interesting result is that after use, the single-crystal electrode showed very little degradation. According to reports, the batteries are already in production and they expect to see them used more often in the near future.

The technology shows promise, too, for other demanding battery applications like grid storage. Of course, better batteries are always welcome, although it is hard to tell which new technologies will catch on and which will be forgotten.

There are many researchers working on making better batteries. Even AI is getting into the act.