Translate Your CP/M Code To 8086, And Leave The 1970s Behind!

June 13, 2021 by 34 Comments

“Bring our home computing out of the 1970s and into the 1980s and beyond” is the irresistible promise made by the creator of 8088ify, a piece of software which translates CP/M executables from their 8080-based originals to assembler code that should run on an 8088 under MS/DOS. How can we resist such a futuristic promise here in 2021, even though the code wasn’t written to the sound of Donna Summer or the Village People back in the day but here in 2021 for PCjam, a celebration of the original IBM PC’s 40th anniversary.

As the writer of this code [ibara] points out that Intel intended the 8088 to be a ready upgrade path for the 8080, and designed its instruction set while not directly compatible, to make translation between the two a straightforward process. There was commercial software for the task at the time, but to this day there remained nothing with an open-source licence. It’s written in ANSI C for portability across platforms and compilers, and can even be compiled under CP/M itself.

PCjam is well worth a look, and if any of you fancy a go at writing for the earliest MS-DOS machines we’d like to suggest you create something for it. Meanwhile if you’d like to explore CP/M, you can run a bare metal emulator on the Raspberry Pi.

Header: Thomas Nguyen, CC BY-SA 4.0.

Roller Skating, Wile E. Coyote-Style

June 13, 2021 by 36 Comments

They say you learn something new every day, and they’re usually right about that. Today’s tidbit is that just anybody (including [Ian Charnas]) can exchange money for jet engines, no questions asked. Scary, huh? So once [Ian] secured the cutest little engine, he took a poll regarding possible uses for it. Jetpack rollerskating won, that’s obvious enough. So let’s get into those details.

[Ian] procured this particular jet engine from an outfit called CRX Turbines. It tops out at 98,000 RPM and 30 kg (66 lbs.) of thrust. Essentially, he is pulsing the engine’s ECU with PWM from an Adafruit RadioFruit and controlling it with a pair of stripped drills that are just being used for their convenient grips and switches. One is wired as a dead man’s switch, and the other controls the throttle signal.

In order to run the thing and test the thrust a bit before strapping it on his back, [Ian] went about this the smart way and welded together a sliding stand. And he didn’t use just any old Jansport backpack, he welded together a frame and roll cage for the engine and attached it to a full-body harness. There’s also a heat shield to keep his backside from catching fire.

At first he tested the jet pack with shoes instead of skates to make sure it was going to behave as he predicted. Then it was time to bust out the roller skates. [Ian] achieved a top speed of 17 MPH before losing his balance, but he knew it could go faster, so he invited some roller derby skaters to try it out. One of them went over 30 MPH! Be sure to check it out in the build and demo video after the break.

If you’re at all familiar with [Ian]’s videos, you know that he usually raffles off the build and gives the money to charity. Well, not this time! That wouldn’t be prudent. Instead, he’s going to choose the best suggestion for what to attach it to, build it, and raffle that off. Hopefully, he stays away from airports with that thing on his back.

Continue reading “Roller Skating, Wile E. Coyote-Style” →

Mickey’s Big Timer Makes Glider Competitions Better

June 13, 2021 by 2 Comments

There’s plenty of obscure sports in the world. Many of them could benefit from bespoke equipment like scoring displays, but are too obscure to support commercial efforts in this regard. Radio controlled glider competitions fit into just this category. This led a man named [Mickey] to develop what he calls Mickey’s Big Timer, to aid in the running of such events.

Glider events run outdoors in full sunlight, so the system uses big bright LED matrix displays to show its timing information. The system, built around the STM32 Discovery platform, uses several of the microcontroller boards to drive several displays as well as the main controller which handles timing. It also packs in an audio system for issuing instructions to competitors. It can also display pilot names as well as instructions such as when competitors should land at the end of a heat.

Some code is available on Github for those interested in how it all works. Word around the RC forums has it that [Mickey] built several systems, some of which ended up as far afield as New Zealand where they helped run many successful glider contests over the years.

We’ve seen plenty of scoreboard projects over the years; a little portable one could be useful for adding some spice to your pickup neighbourhood games. Video after the break.

Continue reading “Mickey’s Big Timer Makes Glider Competitions Better” →

Super Mario Bros. 35 Lives Again With A Fan-Made Server

June 13, 2021 by 27 Comments

If you liked playing Super Mario Bros. 35, the unique multiplayer battle royale Mario game that Nintendo released last year on the Switch to celebrate 35 years since the original NES version of Super Mario Bros, then it’s likely that you have been disappointed since April. The gaming giant ended support and removed the game’s servers once their 35 year celebrations were over, leaving the game’s players hanging. Happily there’s a solution, because [Kinnay] has presented a reverse-engineered Nintendo game server replacement along with a game patch, that should keep gamers in multi-Mario fun forever.

While it’s a boon for fans of this particular game, the real value here is in introducing us to the reverse engineering work on those Nintendo servers. We learn about their various foibles over several generations of console, and perhaps most importantly we learn something of their inner workings.

Usually when a game server is turned off it’s because the platform it supports is so ancient as to have hardly any users. This time-limited game on an up-to-date platform is unusual then, but since it was made available to subscribers to Nintendo’s online service for free it’s less of a surprise. Certainly not in the same class as the loss of servers for an entire platform.

Thanks [Digiaap] for the tip.

Header image: Elvis untot, CC BY-SA 4.0.

Waterslide Decals For Wingding Keycaps

June 12, 2021 by 24 Comments

We know this feeling all too well [YOHON!] spent $340 building, lubing, and filming a custom keyboard and it still wasn’t perfect until they got the keycaps sorted. They bought blank ‘caps because they’re awesome, but also because they wanted to make their own custom ‘caps for all those painstakingly lubed and filmed Gateron yellows. At first [YOHON!] thought about doing it DIY dye-sublimation style with a hair straightener and polyimide tape, but that is too permanent of a method. Instead, [YOHON!] wanted room to experiment, make changes, and make mistakes.

Eventually, [YOHON!] learned about waterslide decals and settled on doing them that way. Every step sounds arduous, but we think it was way worth it because these look great. Since [YOHON!] wanted the keyboard to be weird, they designed a cute little symbol for each key which gives it a cryptic-but-accessible Wingdings feel.

We think these pictograms are all totally adorable, and we particularly like the owl for O, the volcano for V, and of course, the skeleton for X is a solid choice. Oh, and there’s a tiny fidget spinner knob to round out the cuteness. Designing and applying the keycaps took longer than the entire keyboard build, but you can check out the sped-up version after the break.

Want to just throw money at the keycaps problem? You may not want an entire keyboard full of cheeseburger and hot dog keycaps, but one or two fun keycaps are pretty cool to have. If you want to make your custom keycaps more permanent and don’t like the dye sublimation trick, try 3D printing them.

Continue reading “Waterslide Decals For Wingding Keycaps” →

Bungee And Cam Assisted Actuator For OpenDog

June 12, 2021 by 17 Comments

One of the challenges of many walking robot designs is the fact that they draw current just to stay upright. This was exactly the case for one [James Bruton]’s quadruped robots, where the knee motors were getting too hot to touch. Adding springs to take some of the load is not as simple it might seem, so [James] created a bungee assisted cam mechanism to do the job.

For a normal spring-loaded lever, force is proportional to how much the spring is stretched, which will require the actuators to draw more and more current as it lifts the leg higher. For the spring force to remain constant throughout the range of motion, the length of the lever arm must become continuously shorter as the knee is bent.  [James] did this by stretching a bungee cord around a cam. The added bulk of the cam does however cause the knees to knock into each other in some scenarios, but [James] plans to adjust the robot’s gait to avoid this. He didn’t get around to actually measuring the current draw reduction, but the motor temperature has dropped significantly, only being slightly warm after a test run.

These tests were done with OpenDog V2, but [James] is already working on the design of V3, which will use 3D printed cycloidal gearboxes. At the moment, that build is still being delayed thanks to the global component shortage. Continue reading “Bungee And Cam Assisted Actuator For OpenDog” →

3D Print An Entire PC Case

June 12, 2021 by 33 Comments

With laptops having become a commodity item and single-board computers having conquered the lower end for our community, building a PC for yourself is no longer the rite of passage that it once was; except perhaps if you are a gamer. But there is still plenty of fun to be had in selecting and assembling PC hardware, especially if as [makerunit] did, you design and 3D-print your own case.

This is no motherboard in an old pizza box, but instead a highly compact and well-designed receptacle for a reasonable-performance gaming machine with an ITX motherboard. The chassis holding all the parts sits inside a slide-on textured sleeve, and particular attention has been paid to air flow and cooling. The GPU card is a little limited by the size of the case and there’s no room at all for a conventional hard drive, so a PCIe SSD board takes that role.

We’d hazard the opinion that were this case cranked out by the likes of Apple it would be hailed as some kind of design masterpiece, such is its quality. It certainly shows that there’s so much more to building your own PC than the normal rectangular tower case.

Over the decades we’ve brought you so many PC cases, a recent-ish one that’s worth a look is this Lego Minecraft one for an Intel NUC motherboard.

Continue reading “3D Print An Entire PC Case” →