Usually, designing a CPU is a lengthy process, especially so if you’re making a new ISA too. This is something that can take months or even years before you first get code to run. But what if it wasn’t? What if one were to try to make a CPU as fast as humanly possible? That’s what I asked myself a couple weeks ago.
Continue reading “What Happens If You Speedrun Making A CPU?”
It’s been about a decade since Amazon began to fly its delivery drones, aiming to revolutionize the online shopping experience with rapid delivery of certain items. Most recently Amazon got permission from the FAA to not only start flying from its new Arizona-based location, but also to fly beyond-visual-line-of-sight (BVLOS) missions with the new MK30 drone. We reported on this new MK30 drone which was introduced earlier this year along with the news of the Amazon Prime Air delivery service ceasing operations in California and moving them to Arizona instead.
This new drone has got twice the range as the old MK27 drone that it replaces and is said to be significantly quieter as well. The BLOS permission means that the delivery drones can service areas which are not directly visible from the warehouse with its attached drone delivery facility. With some people within the service range of the MK27 drones having previously complained about the noise levels, we will see quickly enough whether the MK30 can appease most.
As for the type of parcels you can have delivered with this service, it is limited to 2.27 kg (~5 lbs), which is plenty for medication and a range of other items where rapid delivery would be desirable.
[David Bryant] clearly has an awareness of the impact of an excess concentration of CO2 in the local environment and has designed an SAO board to add a CO2 traffic light indicator to one of the spare slots on the official Hackaday Supercon 2024 badge.
The part used is the Sensirion SCD40 ‘true’ CO2 sensor, sitting atop an Adafruit rider board. [David] got a leg up on development by creating a simple SAO breakout board, which could have either the male and female connectors fitted, as required. Next, he successfully guessed that the badge would be based around the RP2040 running MicroPython and hooked up an Adafruit Feather RP2040 board to get started on some software to drive the thing. This made hooking up to the official badge an easy job. Since the SAO has only two GPIOs, [David] needed to decode these to drive the three LEDs. There are a few ways to avoid this, but he wanted to relive his earlier EE college years and do it the direct way using a pair of 74HC00 quad NAND gate chips.
We’ve seen a few CO2 monitors over the years. This sleek little unit is based around the Seeeduino XIAO module and uses an LED ring as an indicator. Proper CO2 monitors can be a little pricey, and there are fakes out there. Finally, CO2 is not the only household pollutant; check out this project.
Ideally, if you are going to transmit, you want a properly-tuned resonant antenna. But, sometimes, it isn’t practical. [Ham Radio Rookie] knew about random wire antennas but didn’t want a wire antenna. So, he took carbon fiber extension poles and Faraday tape and made a “random stick” antenna. You can check it out in the video below.
We aren’t sure what normal people are doing with 7-meter-long telescoping poles, but — as you might expect — the carbon fiber is not particularly conductive. That’s where the tape comes in. Each section gets some tape, and when you stretch it out, the tape lines up.
It’s been nearly four years since the Arecibo Telescope collapsed, an event the world got to witness in unprecedented detail thanks to strategically positioned drones. They captured breathtaking video of one of the support cables pulling from its socket as well as the spectacularly destructive results of 900 tons of scientific instruments crashing into the 300-meter primary reflector. But exactly why did those cable sockets fail?
A new report aims to answer that question, and in the process raises some interesting questions of its own. The proximate causes of the collapse have been known for a while, including the most obvious and visible one, the failure of the zinc “spelter sockets” that were cast around the splayed ends of the wire ropes to hold them in place. The new report agrees with this conclusion, at least in part, implicating “zinc creep,” or the tendency for zinc to deform over time under load. Where it appears to differ, though, is with the quality of workmanship on the sockets, finding no issues with the way the individual wires in the failed support cable were manually splayed within the socket before the molten zinc was poured. The report also points out that the collapse probably started when Hurricane Maria swept over Puerto Rico 39 months before the collapse, after which zinc creep in the sockets seemed to accelerate.
But why did the sockets fail? As the report points out, spelter sockets are commonly used to anchor cables that support heavy loads under conditions similar to the tropical climate at Arecibo. After ruling out every other cause, the committee was left with the conclusion that Arecibo itself may have been to blame for the accelerated zinc creep, thanks to electrical currents induced in the cables and sockets when the telescope’s powerful transmitters were used. They call this “long-term, low-current electroplasticity.” Electroplastic effects have been observed since the 1950s, and while far from certain that’s what happened here, the thought is that skin-effect currents induced in the support cables flowed to ground through the zinc sockets, increasing the plasticity of the metal and accelerating the zinc creep that ultimately led to collapse.
Case closed? Hardly. The electroplasticity mechanism for the Arecibo collapse offered by this report is almost a “diagnosis of exclusion” situation. It makes sense, though; since no other spelter sockets have ever failed this way in a century of use, there’s a good chance that the root cause was specific to Arecibo, and since it was once the world’s most powerful radio transmitter, it seems like a red flag that bears further investigation.
As we all know, when developing software for any platform or simply hacking a bit of code to probe how something works, the ability to deploy code rapidly is a huge help. [Martin Donlon], aka [wickerwaka], is well known in retro gaming and arcade hardware reverse engineering circles and had the usual issues figuring out how an arcade CPU board worked while developing a MiSTer core. Some interesting ASICs needed quite a bit of poking, and changing the contents of socketed ERPOMs is a labour-intensive process. The solution was PicoROM, a nicely designed ROM emulator in a handy DIP-32 form factor.
As the title suggests, PicoROM is based on the Raspberry Pi RP2040. It emulates an 8-bit ROM up to 2MBits in size with speeds up to 100ns. Since it uses the RP2040, USB connectivity is simple, enabling rapid uploading of new images to one (or more) PicoROMs in mere seconds. A vertically orientated USB-C connector allows multiple PicoROMs to be cabled to the host without interfering with neighbouring hardware. The firmware running on core 1 passes data from the internal 264K SRAM, using the PIO block as a bus interface to the target. A neat firmware feature is the addition of a mechanism to use a ROM region as a bidirectional control channel, which the software running on the target can use to communicate back to the host computer. This allows remote triggering of actions and the reporting of responses. Responses which may not be physically observable externally. [Martin] is using this feature extensively to help probe the functionality of some special function chips on the target boards, which is still a slow process but helped massively by reducing that critical software iteration time. The PCB was designed with KiCAD. The project files for which can be found here.
This isn’t the first time we’ve seen the RP2040 used for ROM emulation; here’s a pile of wires that does the same job. It just isn’t as pretty. Of course, if you really must use EPROMs, then you could give this sweet programmer a look over.
Here’s a design for a split-flap clock that doesn’t do it the usual way. Instead of the flaps showing numbers , Klapklok has a bit more in common with flip-dot displays.
It’s an art piece that uses custom-made split-flaps which flutter away to update the display as time passes. An array of vertically-mounted flaps creates a sort of low-res display, emulating an analog clock. These are no ordinary actuators, either. The visual contrast and cleanliness of the mechanism is fantastic, and the sound they make is less of a chatter and more of a whisper.
The sound the flaps create and the sight of the high-contrast flaps in motion are intended to be a relaxing and calming way to connect with the concept of time passing. There’s some interactivity built in as well, as the Klapklok also allows one to simply draw on it wirelessly with via a mobile phone.
Klapklok has a total of 69 elements which are all handmade. We imagine there was really no other way to get exactly what the designer had in mind; something many of us can relate to.
Split-flap mechanisms are wonderful for a number of reasons, and if you’re considering making your own be sure to check out this easy and modular DIY reference design before you go about re-inventing the wheel. On the other hand, if you do wish to get clever about actuators maybe check out this flexible PCB that is also its own actuator.
Continue reading “Split-Flap Clock Flutters Its Way To Displaying Time Without Numbers”
