Modern In-Circuit Emulator For The 6809

The Motorola 6809, released in 1978, was the follow-up to their 6800 from four years earlier. It’s a powerful little chip with many 16-bit features, although it’s an 8-bit micro at heart. Despite its great improvements over the 6800, and even technical superiority over the Z80 and 6502 (hardware multiply, for example!), it never reached the same levels of success that those chips did. However, there are still some famous systems, such as the TRS-80 Colour Computer, which utilized the chip and are still being hacked on today. [Ted] is clearly a fan of the 6809, as he used a Teensy 4.1 to create a cycle-exact, drop-in 6809 emulator!

A small interposer board rearranges the Teensy pinout to match the 6809, as well as translating voltage levels from 3.3V to 5V. With careful design, the Teensy matches the cycle diagrams in the Motorola datasheet precisely, and so should be able to run any applications written for the chip! A great test was booting Extended Colour BASIC for the TRS-80 CoCo 2 and running some test BASIC programs. Any issues with opcode decoding or timing would certainly be exposed while running an interpreted language like BASIC. After this successful test, it was time to let the Teensy’s ARM Cortex-M7 rip and see what it could do.

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Watch This RC Jet Thrust System Dance

An EDF (electric duct fan) is a motor that basically functions as a jet engine for RC aircraft. They’re built for speed, but to improve maneuverability (and because it’s super cool) [johnbecker31] designed a 3D-printable method of adjusting the EDF’s thrust on demand.

Before 3D printers were common, making something like this would have been much more work.

The folks at Flite Test released a video in which they built [john]’s design into a squat tester jet that adjusts thrust in sync with the aircraft’s control surfaces, as you can see in the header image above. Speaking of control surfaces, you may notice that test aircraft lacks a rudder. That function is taken over by changing the EDF’s thrust, although it still has ailerons that move in sync with the thrust system.

EDF-powered aircraft weren’t really feasible in the RC scene until modern brushless electric motors combined with the power density of lithium-ion cells changed all that. And with electronics driving so much, and technology like 3D printers making one-off hardware accessible to all, the RC scene continues to be fertile ground for all sorts of fascinating experimentation. Whether it’s slapping an afterburner on an EDF or putting an actual micro jet engine on an RC car.

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Five Ways To Repair Broken PCB Traces

When everything used wires, it was easy to splice them or replace them. Not so much with PC boards, but everyone has their favorite method for repairing a broken trace. [Mr. SolderFix] has his five favorite ways, as you can see in the video below.

Of course, before you can repair a trace, you probably have to expose it since most boards have solder mask now. Unless you plan to shut the trace at both ends, exposing the actual trace is probably the first step.

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Hackable Ham Radio Gives Up Its Mechanical Secrets

Reverse-engineered schematics are de rigeur around these parts, largely because they’re often the key to very cool hardware hacks. We don’t get to see many mechanical reverse-engineering efforts, though, which is a pity because electronic hacks often literally don’t stand on their own. That’s why these reverse-engineered mechanical diagrams of the Quansheng UV-K5 portable amateur radio transceiver really caught our eye.

Part of the reason for the dearth of mechanical diagrams for devices, even one as electrically and computationally hackable as the UV-K5, is that mechanical diagrams are a lot less abstract than a schematic or even firmware. Luckily, this fact didn’t daunt [mdlougheed] from putting a stripped-down UV-K5 under a camera for a series of images to gather the raw data needed by photogrammetry package RealityCapture. The point cloud was thoughtfully scaled to match the dimensions of the radio’s reverse-engineered PC board, so the two models can work together.

The results are pretty impressive, especially for a first effort, and should make electromechanical modifications to the radio all the easier to accomplish. Hats off to [mdlougheed] for the good work, and let the mechanical hacks begin.

Solar Dynamics Observatory: Our Solar Early Warning System

Ever since the beginning of the Space Age, the inner planets and the Earth-Moon system have received the lion’s share of attention. That makes sense; it’s a whole lot easier to get to the Moon, or even to Mars, than it is to get to Saturn or Neptune. And so our probes have mostly plied the relatively cozy confines inside the asteroid belt, visiting every world within them and sometimes landing on the surface and making a few holes or even leaving some footprints.

But there’s still one place within this warm and familiar neighborhood that remains mysterious and relatively unvisited: the Sun. That seems strange, since our star is the source of all energy for our world and the system in general, and its constant emissions across the electromagnetic spectrum and its occasional physical outbursts are literally a matter of life and death for us. When the Sun sneezes, we can get sick, and it has the potential to be far worse than just a cold.

While we’ve had a succession of satellites over the last decades that have specialized in watching the Sun, it’s not the easiest celestial body to observe. Most spacecraft go to great lengths to avoid the Sun’s abuse, and building anything to withstand the lashing our star can dish out is a tough task. But there’s one satellite that takes everything that the Sun dishes out and turns it into a near-constant stream of high-quality data, and it’s been doing it for almost 15 years now. The Solar Dynamics Observatory, or SDO, has also provided stunning images of the Sun, like this CGI-like sequence of a failed solar eruption. Images like that have captured imaginations during this surprisingly active solar cycle, and emphasized the importance of SDO in our solar early warning system.

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The Flash Memory Lifespan Question: Why QLC May Be NAND Flash’s Swan Song

The late 1990s saw the widespread introduction of solid-state storage based around NAND Flash. Ranging from memory cards for portable devices to storage for desktops and laptops, the data storage future was prophesied to rid us of the shackles of magnetic storage that had held us down until then. As solid-state drives (SSDs) took off in the consumer market, there were those who confidently knew that before long everyone would be using SSDs and hard-disk drives (HDDs) would be relegated to the dust bin of history as the price per gigabyte and general performance of SSDs would just be too competitive.

Fast-forward a number of years, and we are now in a timeline where people are modifying SSDs to have less storage space, just so that their performance and lifespan are less terrible. The reason for this is that by now NAND Flash has hit a number of limits that prevent it from further scaling density-wise, mostly in terms of its feature size. Workarounds include stacking more layers on top of each other (3D NAND) and increasing the number of voltage levels – and thus bits – within an individual cell. Although this has boosted the storage capacity, the transition from single-level cell (SLC) to multi-level (MLC) and today’s TLC and QLC NAND Flash have come at severe penalties, mostly in the form of limited write cycles and much reduced transfer speeds.

So how did we get here, and is there life beyond QLC NAND Flash?

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Hackaday Links: July 7, 2024

Begun, the Spectrum Wars have. First, it was AM radio getting the shaft (last item) and being yanked out of cars for the supposed impossibility of peaceful coexistence with rolling broadband EMI generators EVs. That battle has gone back and forth for the last year or two here in the US, with lawmakers even getting involved at one point (first item) by threatening legislation to make terrestrial AM radio available in every car sold. We’re honestly not sure where it stands now in the US, but now the Swiss seem to be entering the fray a little up the dial by turning off all their analog FM broadcasts at the end of the year. This doesn’t seem to be related to interference — after all, no static at all — but more from the standpoint of reclaiming spectrum that’s no longer turning a profit. There are apparently very few analog FM receivers in use in Switzerland anymore, with everyone having switched to DAB+ or streaming to get their music fix, and keeping FM transmitters on the air isn’t cheap, so the numbers are just stacked against the analog stations. It’s hard to say if this is a portent of things to come in other parts of the world, but it certainly doesn’t bode well for the overall health of terrestrial broadcasting. “First they came for AM radio, and I did nothing because I’m not old enough to listen to AM radio. But then they came for analog FM radio, and when I lost my album-oriented classic rock station, I realized that I’m actually old enough for AM.”

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