A Quite Obscure C128 Video Mode Hack

30 years ago, [Dave] found himself up a C128D creek without a paddle. His main monitor was on the fritz, and he needed to use his C128D in 40-column mode to run old C64 programs for development purposes. Normally this is only possible through the low quality composite out, but no composite monitor was available. Needs must, so he got to coding a workaround that would allow the C128D to output in 40 column mode through the higher-quality RGBI output. 

It’s a proper old-school hack in the spirit of the 8-bit era. The C64 ROM is copied into RAM, where it’s then modified to instead update a 40-column image that’s sent to the RGBI display hardware. The original C64 character ROM is also copied over to ensure everything displays correctly.

It’s not bulletproof, and a few pokes to the wrong memory locations have a high likelihood of crashing the system, seeing as the ROM is now in RAM. However, it does allow the user to enable FAST mode and use all the C128 extended keys. [Dave] recommends experimenting in an emulator first, lest you scare your vintage monitor with angry signals it can’t understand.

The C128 was Commdore’s last 8-bit computer on the market, and there’s a heck of a story behind its creation.

Building Keyboards With Resin Printers

Aside from putting a whole lot of tact switches on a board, no one has quite figured out how to make very small keyboards for wearable projects. [Madaeon] might have the answer, and it’s using a resin-based 3D printer to create a flexible keyboard without silicone.

The world of small keyboards is filled with what are effectively the squishy parts of a remote control. This uses a piece of silicone and tiny carbon ‘dots’ on the underside of each button. Press the button, and these carbon dots bridge two traces on a PCB, closing a switch. No one has yet mastered home-casting silicone, although the people behind the ESP32 WiPhone have been experimenting with aluminum molds.

Instead of going down the path of casting and curing silicone, [Madaeon] decided to use 3D printing, specifically resin 3D printing, using a very flexible resin. The build process is what you would expect — just some button-shaped objects, but this gets clever when it comes to bridging the connections on the keyboard matrix. This is done with conductive paint, carefully applied to the underside of each button.

Right now this is a viable means of getting a tiny keyboard easily. The color is a garish pink, and the labels on each button aren’t quite as visible as anyone would like, but the latter can be fixed with silkscreening, just like how it’s done on the silicone buttons for remote controls.

6th Annual Hackaday X Tindie MFBA Meetup With A New, Larger Venue

We want to hang out with you at Maker Faire Bay Area! Put our after-hours meetup on your schedule with a Sharpie, because the 6th Annual Hackaday x Tindie MFBA Meetup w/ Kickstarter will be bigger and better than ever with a new venue that has plenty of room for everyone!

The hacker crowd descends upon San Mateo weekend after next to show off a year of creations at Maker Faire. On Saturday, May 18th, the Faire will close for the evening as our meetup heats up. Bring along some hardware to show off and get the conversation started. Whether you’re attending the Faire or staffing a booth all day, this is the perfect way to unwind.

New Place with More Space!

Every year we’ve been packed to the gills and it’s time to make room for more people. This year Hackaday and Tindie have teamed up with Kickstarter to rent out the entire B Street Station in San Mateo. It’s close by and has plenty of room to hang out with friends new and old. We’ll provide light food and the first drink is on us! Please RSVP so we know how many people to expect, and like we said, grab a project to bring along! This event is open to all who are 21 years of age or older.

Begin Your Weekend with HDDG on Thursday

Start the weekend off right with the HDDG meetup on Thursday night. In keeping with tradition, this special Maker Faire edition of the Hardware Developer’s Didactic Galactic is happen at the San Francisco Supplyframe office on May 16th. You’ll find a ton of people from out of town on hand to enjoy talks ranging from non-rectangular phone design and mitigating ESD in wearables, to getting your projects funded with PR stunts. Speakers include Christina Cyr, Mary West, and Mic Black.

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Supercapacitors Propel Rocket To The Skies

OK, so this isn’t really a rocket. In the strictest definition, rockets are vehicles or projectiles that propel themselves through jettisoning mass, usually through the combustion of fuel. But with electric motors getting stronger and stronger, folks are building craft that look a lot more like rockets than airplanes. [Tom Stanton] is one such person (Youtube link, embedded below).

We’ve seen “electric rocket” builds before, but where others have used lithium batteries, [Tom] has used supercapacitors instead. Six supercaps are installed in a 3D printed mount, and supply power to a 500 W brushless outrunner motor which gives the rocket the thrust to climb into the sky.

In testing, [Tom] estimates the rocket was able to reach an altitude of approximately 60 m, or 200 ft. That’s not particularly astounding, but it does prove that supercaps can run a high current load in a real world situation. Additionally, their fast recharge rate allows [Tom] to make a repeat flights in just about the time it takes to repack the parachute. Video after the break.

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How Art Became Science In Machining

Machining is one of those fascinating fields that bridges the pre-scientific and scientific eras. As such, it has gone from a discipline full of home-spun acquired wisdom and crusty old superstitions to one of rigorously analyzed physics and crusty old superstitions.

The earliest machinists figured out most of what you need to know just by jamming a tool bit into spinning stock and seeing what happens. Change a few things, and see what happens next. There is a kind of informal experimentation taking place here. People are gradually controlling for variables and getting better at the craft as they learn what seems to affect what. However, the difference between fumbling around and actually knowing something is controlling for one’s own biases in a reproducible and falsifiable way. It’s the only way to know for sure what is true, and we call this “science”. It also means being willing to let go of ideas you had because the double-blinded evidence clearly says they are wrong.

That last part is where human nature lets us down the most. We really want to believe things that confirm our preconceived notions about the world, justify our emotions, or make us feel better. The funny thing about science, though, is that it doesn’t care whether you believe in it or not. So go get your kids vaccinated, and up your machining game with scientific precision. Let’s take a look.

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Lots Of Blinky! ESP32 Drives 20,000 WS2812 LEDs

20,000 LEDs sounds like an amazing amount of blink. When we start to consider the process of putting together 20,000 of anything, and then controlling them all with a small piece of electronics the size of a postage stamp, we get a little bit dizzy. Continue reading “Lots Of Blinky! ESP32 Drives 20,000 WS2812 LEDs”