If you have never heard of the Bellmac-32, you aren’t alone. But it is a good bet that most, if not all, of the CPUs in your devices today use technology pioneered by this early 32-bit CPU. The chip was honored with the IEEE Milestone award, and [Willie Jones] explains why in a recent post in Spectrum.
The chip dates from the late 1970s. AT&T’s Bell Labs had a virtual monopoly on phones in the United States, but that was changing, and the government was pressing for divestiture. However, regulators finally allowed Bell to enter the computing market. There was only one problem: everyone else had a huge head start.
There was only one thing to do. There was no point in trying to catch the leaders. Bell decided to leap ahead of the pack. In a time when 8-bit processors were the norm and there were nascent 16-bit processors, they produced a 32-bit processor that ran at a — for the time — snappy 2 MHz.
It is no secret that we like slide rules around the Hackaday bunker, and among our favorites are the cylindrical slide rules. [Chris Staecker] likes them, too, and recently even 3D printed a version. But spurred by comments on his video, he decided to try something that might be unique: a helical slide rule. You can see how it works in the video below.
With a conventional slide rule, the scale is rotated around a cylinder so that it is the same length as a much longer linear scale. However, this new slide rule bends the entire rule around a cylinder and allows the slide to move, just like a conventional slide rule. If you have a 3D printer, you can make your own.
For those of us who’ve spent far too long hammering rubber keys into submission, a glorious solution has arrived. [Lee Smith] designed the ZX Mechtrum Deluxe, the ultimate keyboard upgrade for your beloved ZX Spectrum 48k. Thanks to [morefunmakingit], you can see this build-it-yourself mechanical mod below. It finally brings a proper spacebar and Spectrum-themed Wraith keycaps into your retro life.
The Metrum Deluxe is a full PCB redesign: no reused matrices or clunky membrane adapters here. [Lee Smith] got fed up with people (read: the community, plus one very persistent YouTuber) asking for a better typing experience, so he delivered. Wraith keycaps from AliExpress echo the original token commands and BASIC vibe, without going full collector-crazy. Best of all: the files are open. You can download the case on Printables and order the PCB through JLCPCB. Cherry on top (pun intended): you’ll finally have a spacebar your thumbs can be proud of.
So whether you’re into Frankenstein rigs or just want your Spectrum to stop feeling like an air mattress, check this video out. Build files and link to the keycaps can be found on Youtube, below the video.
Tip: if you foster a secret love for keyboards, don’t miss the Keebin’ with Kristina’s series on all sorts of keyboards.
Have you ever heard of INTERCAL? If you haven’t, don’t feel bad. This relatively obscure language dates back to 1972 with the goal of being difficult to read and write. It is the intellectual parent of systems like brainf**k and other bad languages. Now, you can read the INTERCAL-72 source code thanks to a found printout. It will help if you can read SPITBOL, another obscure language that is a compiled version of SNOBOL (which is like an old-fashioned non-Unix awk program).
How strange it INTERCAL? Well, one of the statements is PLEASE. If you don’t use it enough, you’ll offend the interpreter, who will then ignore your program. But if you use it too much, then you are a suck up and, therefore, your program will be ignored again. If you think GOTO is a bad idea, you’ll just hate COME FROM, although that was from a later version of INTERCAL.
If you’re into retro CPUs and don’t shy away from wiring old-school voltages, [Mark]’s latest Intel 8080 build will surely spark your enthusiasm. [Mark] has built a full system board for the venerable 8080A-1, pushing it to run at a slick 3.125 MHz. Remarkable is that he’s done so using a modern Microchip FPGA, without vendor lock-in or proprietary flashing tools. Every step is open source.
Getting this vintage setup to work required more than logical tinkering. Mark’s board supplies the ±5 V and +12 V rails the 8080 demands, plus clock and memory interfacing via the M2GL005-TQG144I FPGA. The design is lean: two-layer PCB, basic level-shifters, and a CM32 micro as USB-to-UART fallback. Not everything went smoothly: incorrect footprints, misrouted gate drivers, thermal runaway in the clock section; but he managed to tackle it.
What sets this project apart is the resurrection of a nearly 50-year-old CPU. It’s also, how thoroughly thought-out the modern bridge is—from bitstream loading via OpenOCD to clever debugging of crystal oscillator drift using a scope. [Mark]’s love of the architecture and attention to low-level detail makes this more than a show-off build. Continue reading “Vintage Intel 8080 Runs On A Modern FPGA”→
It does, more-or-less, what it says as on the tin: it is an HTTP proxy that retrieves pages from the Internet Archive’s Wayback Machine, or the Oocities archive of old Geocities sites. (Remember Geocities?) It is meant to sit on a Raspberry Pi or similar SBC between you and the modern internet. A line in a config file lets you specify the exact date. We found this via YouTube in a video by [The Science Elf] (embedded below, for those of you who don’t despise YouTube) in which he attaches a small screen and dial to his Pi to create what he calls the “Internet Time Machine” using the Wayback Proxy. (Sadly [The Science Elf] did not see fit to share his work, but it would not be difficult to recreate the python script that edits config.json.)
What’s the point? Well, if you have a retro-computer from the late 90s or early 2000s, you’re missing out a key part of the vintage experience without access to the vintage internet. This was the era when desktops were being advertised as made to get you “Online”. Using Wayback Proxy lets you relive those halcyon days– or live them for the first time, for the younger set. At least relive those of which parts of the old internet which could be Archived, which sadly isn’t everything. Still, for a nostalgia trip, or a living history exhibit to show the kids? It sounds delightful.
As you might imagine, this project got its start with the RP2040-based Pico Mac project by [Matt Evans], which we covered
The collector’s edition will come with a lovely box, but what’s in it is still open source so you can make your own.
before. [Nick] saw that, built it, and was delighted by it enough to think that if the Mac could run on such tiny hardware, how small could build a fully-usable replica Mac? The answer was 63 mm tall– at 5.5:1, that’s technically under the 6:1 scale that Barbie operates on, but if we had such a dollhouse we’d absolutely put one of these in it. (You just know Barbie’s an Apple kind of girl.)
The size was driven by the screen, which is a 2″ TFT panel with 480 x 640 pixel native resolution. Here [Nick] cheats a tiny bit– rather than trying to rewrite the PicoMac to output 640 x 480 and rotate the screen, he keeps the screen in portrait mode and drives it at 480 x 342 px. Sure, it’s not a pixel-perfect output, but no LCD is going to be a perfect stand in for a CRT, and who is going to notice 32 pixels on a 2″ screen? Regardless, that set the height of the computer, which is built around the portrait display. A highly detailed, and to our eyes, accurate replica of the original Macintosh case was printed to fit the LCD, coming in at the aforementioned 63mm tall.
Unfortunately this means the floppy drive could not be used for micro SD access– there is an SD card reader on this unit, but it’s on the back, along with a USB-C port, which is roughly where the mouse and keyboard ports are supposed to be, which is a lovely detail. Also delightful is the choice of a CR2 lithium battery for power, which is a form factor that will look just a bit familiar if you’ve been inside one of these old Macs.
