Another World On The Apple II

August 26, 2019 by Maya Posch 11 Comments

What’s more fun than porting an old game released for an old system such as the Apple IIgs to its 10-year-older predecessor, the Apple II from 1977? Cue [Deater]’s port of the classic video game ‘Another World‘ to the original Apple II. As was fairly obvious from the onset, the main challenges were with the amount of RAM, as well as with the offered graphics resolutions.

Whereas the Apple II could address up to 48 kB of RAM, the 16-bit Apple IIgs with 65C816 processor could be upgraded to a maximum of 8 MB. The graphics modes offered by the latter also allowed ‘Another World’ to run at a highly playable 320×200, whereas the ported version is currently limited to the ‘low resolution’ mode at 40×48 pixels.

The game itself still needs a lot of work to add missing parts and fix bugs, but considering that it has been implemented in 6502 assembler from scratch, using just the gameplay of the IIgs version as reference, it’s most definitely an achievement which would have earned [Deater] a lot of respect back in the late ’80s as well.

Feel free to check out the Github page for this project, grab a floppy disk image from the project page and get playing. Don’t forget to check out the gameplay video linked after the break as well.

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Quantum Radar Hides In Plain Sight

August 26, 2019 by Al Williams 38 Comments

Radar was a great invention that made air travel much safer and weather prediction more accurate, indeed it is even credited with winning the Battle of Britain. However, it carries a little problem with it during times of war. Painting a target with radar (or even sonar) is equivalent to standing up and wildly waving a red flag in front of your enemy, which is why for example submarines often run silent and only listen, or why fighter aircraft often rely on guidance from another aircraft. However, researchers in Italy, the UK, the US, and Austria have built a proof-of-concept radar that is very difficult to detect which relies upon quantum entanglement.

Despite quantum physics being hard to follow, the concept for the radar is pretty easy to understand. First, they generate an entangled pair of microwave photons, a task they perform with a Josephson phase converter. Then they store an “idle” photon while sending the “signal” photon out into the world. Detecting a single photon coming back is prone to noise, but in this case detecting the signal photon disturbs the idle photon and is reasonably easy to detect. It is likely that the entanglement will no longer be intact by the time of the return, but the correlation between the two photons remains detectable.

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Debug Superpowers Bring An STM32 Back From The Dead

August 26, 2019 by Kerry Scharfglass 5 Comments

When a processor has a fault it can leave what looks to be precious little in the way of cause and effect. Debug-by-print-statement works surprisingly well in simple cases, but where in a desktop environment you would drop into a debugger to solve trickier problems this can be an onerous task on an embedded system. [Ross Schlaikjer]’s excellent blog post walks through setting up one of our favorite Open Hardware debug probes and shows us that with the right tooling in place, unexpected faults aren’t quite so impenetrable. Continue reading “Debug Superpowers Bring An STM32 Back From The Dead” →

3D Printed Pen Plotter Is As Big As You Need It To Be

August 26, 2019 by Tom Nardi 16 Comments

There’s nothing quite like building something to your own personal specifications. It’s why desktop 3D printers are such a powerful tool, and why this scalable plotter from the [Lost Projects Office] is so appealing. You just print out the end pieces and then pair it with rods of your desired length. If you’ve got some unusually large computer-controlled scribbling in mind, this is the project for you.

The design, which the team calls the Deep Ink Diver (d.i.d) is inspired by another plotter that [JuanGg] created. While the fundamentals are the same, d.i.d admittedly looks quite a bit more polished. In fact, if your 3D printed parts look good enough, this could probably pass for a commercial product.

For the electronics, the plotter uses an Arduino Uno and a matching CNC Shield. Two NEMA 17 stepper motors are used for motion: one to spin the rod that advances the paper, and the other connected to a standard GT2 belt and pulley to move the pen back and forth.

We particularly like the way [Lost Projects Office] handled lifting the pen off the paper. In the original design a solenoid was used, which took a bit of extra circuitry to drive from the CNC Shield. But for the d.i.d, a standard SG90 servo is used to lift up the arm that the pen is attached to. A small piece of elastic puts tension on the assembly so it will drop back down when the servo releases.

If this plotter isn’t quite what you’re after, don’t worry. There’s more where that came from. We’ve seen a number of very interesting 3D printed plotters that are just begging for a spot in your OctoPrint queue.

Candy-Colored Synth Sounds Sweet

August 26, 2019 by Kristina Panos 14 Comments

Let’s face it, synthesizers are awesome. But commercial synths are pretty expensive. Even the little toy ones like the KORG Volca and the MicroKORG will run you a few hundred bucks. For the most part, they’re worth the price because they’re packed with features. This is great for experienced synth wizards, but can be intimidating to those who just want to make some bleeps and bloops.

[Kenneth] caught the mini-synth bug, but can’t afford to catch ’em all. After a visit to the Moog factory, he was inspired to engineer his own box based on the Moog Sirin. The result is KELPIE, an extremely portable and capable synth with 12 voices, 16 knobs, and 4 LED buttons. KELPIE is plug and play—power and a MIDI device, like a keyboard, are the only requirements. It has both 1/8″ and 1/4″ jacks in addition to a standard MIDI DIN connection. [Kenneth] rolled his own board based on the Teensy 3.2 chip and the Teensy audio shield.

Part of the reason Kenneth built this synthesizer is to practice designing a product from the ground up. Throughout the process, he has tried to keep both the production line and the DIYer in mind: the prototype is a two-part resin print, but the design could also be injection molded.

We love that KELPIE takes its visual design cues from the translucent candy-colored Game Boys of the late 90s. (We had the purple one, but always lusted after the see-through kind.) Can we talk about those knobs? Those are resin-printed, too. To color the indicators, [Kenneth] used the crayon technique, which amounts to dripping molten crayon into the groove and scraping it off once hardened. Don’t delay; glide past the break to watch a demo.

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Linux Fu: It’s A Trap!

August 26, 2019 by Al Williams 14 Comments

It is easy to think that a Linux shell like Bash is just a way to enter commands at a terminal. But, in fact, it is also a powerful programming language as we’ve seen from projects ranging from web servers to simple utilities to make dangerous commands safer. Like most programming languages, though, there are multiple layers of complexity. You can spend a little time and get by or you can invest more time and learn about the language and, hopefully, write more robust programs.

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Parallax Update Hack Chat

August 26, 2019 by Dan Maloney 8 Comments

Join us on Wednesday, August 28th at noon Pacific for the Parallax Update Hack Chat with Chip and Ken Gracey!

For a lot of us, our first exposure to the world of microcontrollers was through the offerings of Parallax, Inc. Perhaps you were interested in doing something small and light, and hoping to leverage your programming skills from an IBM-PC or an Apple ][, you chanced upon the magic of the BASIC Stamp. Or maybe you had a teacher who built a robotics class around a Boe-Bot, or you joined a FIRST Robotics team that used some Parallax sensors.

Whatever your relationship with Parallax products is, there’s no doubting that they were at the forefront of the hobbyist microcontroller revolution. Nor can you doubt that Parallax is about a lot more than BASIC Stamps these days. Its popular multicore Propeller chip has been gaining a passionate following since its 2006 introduction and has found its way into tons of projects, many of which we’ve featured on Hackaday. And now, its long-awaited successor, the Propeller 2, is almost ready to hit the market.

The Gracey brothers have been the men behind Parallax from the beginning, with Chip designing all the products and Ken running the business. They’ll be joining us on the Hack Chat to catch us up on everything new at Parallax, and to give us the lowdown on the P2. Be sure to stop be with your Parallax questions, or just to say hi.

Our Hack Chats are live community events in the Hackaday.io Hack Chat group messaging. This week we’ll be sitting down on Wednesday, August 28 at 12:00 PM Pacific time. If time zones have got you down, we have a handy time zone converter.

Click that speech bubble to the right, and you’ll be taken directly to the Hack Chat group on Hackaday.io. You don’t have to wait until Wednesday; join whenever you want and you can see what the community is talking about.