An Old Video Game Controller On Even Older Computer

For those of us not old enough to remember, and also probably living in the States, there was a relatively obscure computer built by Microsoft in the early 80s that had the strong Commodore/Atari vibe of computers that were produced before PCs took over. It was known as the MSX and only saw limited release in the US, although was popular in Japan and elsewhere. If you happen to have one of these and you’d like to play some video games on it, though, there’s now a driver (of sorts) for SNES controllers.

While the usefulness of this hack for others may not help too many people, the simplicity of the project is elegant for such “ancient” technology. The project takes advantage of some quirks in BASIC for reading a touch-pad digitizer connected to the joystick port using the SPI protocol. This is similar enough to the protocol used by NES/SNES controllers that it’s about as plug-and-play as 80s and 90s hardware can get. From there, the old game pad can be used for anything that the MSX joystick could be used for.

We’ve seen a handful of projects involving the MSX, so while it’s not as popular as Apple or Commodore, it’s not entirely forgotten, either. In fact, this isn’t even the first time someone has retrofitted a newer gaming controller to an MSX: the Wii Nunchuck already works for these machines.

Classic British Phone Gets A Google Makeover

It may seem like an odd concept to younger readers, but there was once a time when people rented their phones rather than buying them outright. Accordingly, these phones were built like tanks, and seeing one of these sturdy classics of midcentury modern design can be a trip down memory lane for some of us. So retrofitting a retro phone with a Raspberry Pi and Google’s AIY seems like a natural project to tackle for nostalgia’s sake.

The phone that [Alasdair Allan] decided to hack was the iconic British desk telephone, the GPO-746, or at least a modern interpretation of the default rental phone from the late 60s through the 70s. But the phone’s looks were more important than its guts, which were stripped away to make room for the Raspberry Pi and Google AIY hat. [Alasdair] originally thought he’d interface the Pi to the rotary dial through DIOs, until he discovered the odd optical interface of the dialer — a mask rotates over a ring of photoresistors, one for each digit, exposing only one to light from an LED illuminated by a microswitch on the finger stop. The digital interface brings up the Google voice assistant, along with some realistic retro phone line sounds. It’s a work in progress, but you can see where [Alasdair] is in the video below.

If stuffing a Google Pi into a retro appliance sounds familiar, it might be this vintage intercom rebuild you have in mind, which [Alasdair] cites as inspiration for his build.

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The 1980s Called – Asking For The Z80 Membership Card

The ’80’s and early ’90’s saw a huge proliferation of “personal” computers, spawning an army of hacker kids who would go on to hone their computing chops on 8-bit and 16-bit computers from brands such as Sinclair, Commodore, Acorn, Apple, Atari, Tandy/RadioShack and Texas Instruments. Fast forward to 2017, and Raspberry-Pi, BeagleBone and micro:bit computers reign supreme. But the old 8-bit and 16-bit computer systems can still teach us a lot.

[Lee Hart] has built the amazing Z80 Membership Card — a Z80 computer that fits in an Altoids tin. His design uses generic through hole parts mounted on a PCB with large pads, thick tracks and lots of track clearances, making assembly easy. Add to this his detailed documentation, where he weaves some amazing story telling, and it makes for a really enjoyable, nostalgic build. It makes you want to get under the hood and learn about computers all over again. The Z80 Membership Card features a Zilog Z80 microprocessor running at 4 MHz with 32k RAM and 32K EPROM, loaded with BASIC interpreter and monitor programs. A pair of 30-pin headers provide connections to power, I/O pins, data, address and control signals.

To accompany this board, he’s built a couple of companion “shield” boards. The Front Panel Card has a 16-key hex pad, 7-digit 7-segment LED display and Serial port. [Lee] has packed in a ton of features on the custom monitor ROM for the front panel card making it a versatile, two board, 8-bit system. Recently, he finished testing a third board in this series — a Serial/SD-Card/RAM shield which adds bank-switchable RAM and SD-card interface to provide “disk” storage. He’s managed to run a full CP/M-80 operating system on it using 64k of RAM. The two-board stack fits nicely in a regular Altoids tin. A fellow hacker who built the three-board sandwich found it too tall for the Altoids tin, and shared the design for a 3D printable enclosure.

[Lee] provides detailed documentation about the project on his blog with schematics, assembly instructions and code. He’s happy to answer questions from anyone who wants help building this computer. Do check out all of his other projects, a couple of which we’ve covered in the past. Check out Lee Hart’s Membership Card — a similar Altoids tin sized tribute to the 1802 CMOS chip and how he’s Anthropomorphizing Microprocessors.

Finally, we have to stress this once again — check out his Assembly Manuals [PDF, exhibit #1] — they are amazingly entertaining.

Thanks to [Matthew Kelley] who grabbed one of [Lee]’s kits and then tipped us off.

3D Printed Math Grenade

Calculator hacks are fun and educational and an awesome way to show-off how 1337 your skills are. [Marcus Wu] is a maker who likes 3D printing and his Jumbo Curta Mechanical Calculator is a project from a different era. For those who are unfamiliar with the Curta, it is a mechanical calculator that was the brainchild of Curt Herzstark of Austria from the 1930s. The most interesting things about the design were the compactness and the complexity which baffled its first owners.

The contraption has setting sliders for input digits on the side of the main cylindrical body. A crank at the top of the device allows for operations such as addition and subtraction with multiplication and division requiring a series of additional carriage shift operations. The result appears at the top of the device after each crank rotation that performs the desired mathematical operation. And though all this may seem cumbersome, the original device fit comfortably in one hand which consequently gave it the nick name ‘Math Grenade’.

[Marcus Wu] has shared all the 3D printable parts on Thingiverse for you to make your own and you should really take a look at the video below for a quick demo of the final device. There is also a detailed set of images (82 or so) here that present all the parts to be printed. This project will test your patience but the result is sure to impress your friends. For those looking to dip your toes in big printed machines, check out these Big Slew Bearings for some inspiration.

Dual Trace Scope 1939 Style

If you buy a serious scope these days, it is a good bet it will have at least two channels. There is a lot of value to being able to see two signals in relation to one another at one time. Even though the dual-trace oscilloscope goes back to 1938, they were uncommon and expensive for many years. [Mr. Carlson] found a device from 1939 that would turn a single channel scope into a dual trace scope. In 1939, that was quite the engineering feat.

Today, a dual trace scope is very likely to be digital. But some analog scopes used CRTs with multiple beams to actually draw two traces on the same screen. Most, however, would draw either one trace followed by the other (alternate mode) or rapidly switch between channels (chopper mode). This Sylvania type 104 electronic switch looks like it takes the alternate approach, switching between signals on each sweep using vacuum tubes. You can see the device in action in the video, below.

The inputs and outputs of the device are just simple binding posts, but the unit looked to be in good shape except for the power cord. [Mr. Carlson] does a teardown and he even traced out a hand-drawn schematic. Fair warning. The video is pretty long. If you want to get right to the switch actually driving a scope, that’s at about one hour and seven minutes in.

We doubt we’ll see a tube-based Quake game anytime soon. If you want to get into restoring old tube-based gear yourself, you could do worse than read about radio restoration.

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Retro-Styled Raspberry Pi Radio

Ok, so you want a radio — but not just any radio. It has to be wireless, access a variety of music services, and must have a vintage aesthetic that belies its modern innards. Oh, and a tiny screen that displays album art, because that’s always awesome. This 1938 Emerson AX212-inspired radio delivers.

Building on the backbone of a Raspberry Pi Zero W and an Adafruit MAX 98357 mono amp chip, the crux of this single-speaker radio is the program Mopidy. Mopidy is a music player that enables streaming from multiple services, with the stipulation that you have a premium Spotify account. Once signed up, [Tinkernut] helpfully outlines how to set up Mopidy to run automatically once the Pi boots up. The addition of a screen to display album art adds flair to the design,  and Adafruit’s 1.8″ TFT LCD screen is small enough to fit the bill.

But wait — there’s more!

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Restoring A Retro 747 Control Display Unit

Anyone who’s into retro aviation gear falls in love with those mysterious displays, dials, keypads, banks of knife switches. There’s a lot of sexy in those devices, built with high standards in a time when a lot of it was assembled by hand.

[Jeremy Gilbert] bought a 747-200’s Control Display Unit (CDU)– the interface with the late ’70s in-flight computer–and is bringing it back to life in a Hackaday.io project. His goal is to get it to light up and operate just as if it were installed in a 747.

Of particular interest is the display, which turned out to consist of a series of 5×7 matrices (seen on the right) controlled by chips no one uses any more. However, [Jeremy] found a blog post where someone had hacked out Arduino code for a cousin of the chip, saving him a lot of time. However, he’s got a lot more sleuthing yet to do.

If you’re into retro displays, we’ve mentioned a number of good ones, including the legendary Apollo DSKY and an awesome retrocomputer.