Microcontrollers are getting faster and faster, as is most of the rest of the computing world. Just like you can play Nintendo console games on the newest Nintendo handhelds, it seems that modern microcontrollers can replace CPUs on personal computers from the 80s. At least, that’s what [Dave] has shown with his latest project: an Atmel microcontroller that directly attaches to the CPU slot on a Commodore PET.
Essentially, the project started out as a test rig of sorts for the Commodore. [Dave] wanted to see if some of the hardware on the Commodore was still functional and behaving properly. From there, it somewhat snowballed. The address bus was easy enough to investigate, but adding only a few more pins on the microcontroller he was already using would be enough to access the databus too. A character table was soon added, a test algorithm, and more useful insights. It’s a masterful manipulation of this older hardware with modern technology and is definitely worth a look.
There’s a lot more going on in the retrocomputing world than meets the eye. One might think these old computers were all in landfills by now, but there is a devoted fanbase that does everything from building new hard drives for old computers or investigating their true audio-visual potential.
Thanks to [Mike w] for the tip!
Looking to add some activity to your day but don’t want to go through a lot of effort? [D10D3] has the perfect solution that enables you to take a leisurely bike ride through Skyrim. A standing bicycle combines with an HTC Vive (using the add-on driver VorpX which allows non-vr enabled games to be played with a VR headset) and a Makey Makey board to make slack-xercise — that’s a word now — part of your daily gaming regimen.
The Makey Makey is the backbone of the rig; it allows the user to set up their own inputs with electrical contacts that correspond to keyboard and mouse inputs, thereby allowing one to play a video game in some potentially unorthodox ways — in this case, riding a bicycle.
Setting up a couple buttons for controlling the Dragonborn proved to be a simple process. Buttons controlling some of the main inputs were plugged into a breadboard circuit which was then connected to the Makey Makey along with the ground wires using jumpers. As a neat addition, some aluminium foil served as excellent contacts for the handlebars to act as the look left and right inputs. That proved to be a disorienting addition considering the Vive’s head tracking also moves the camera. Continue reading “Staying In and Playing Skyrim Has Rarely Been This Healthy”
[AbyssalUnderlord’s] schedule has him packing up and moving between school, home, and internships every three months. Not an easy task when your computer is a triple monitor CAD and gaming powerhouse. To make his moves easier, he built this portable computer / monitor frame.
The design started with a CAD model. The basic materials for the build are aluminum angle and steel-slotted angle stock. There was no welding involved in this build. Pop rivets, nuts, and bolts hold just about everything together. An angle grinder was used for all of the cutting. [AbyssalUnderlord] used drawer slides to move his monitors from stored to deployed position. The small red extensions at the end of the drawer slides allow the monitors to be positioned in a standard 3 wide triple monitor setup. It’s a clever design.
This schedule isn’t going to last forever so [AbyssalUnderlord] didn’t want to make any permanent mods to his tower or monitors. Blue camping foam acts as a cushion between the hardware and the new case.
We’ll admit that this isn’t the prettiest of builds, but it looks plenty rugged and it gets the job done. As mentioned in the Reddit thread, a few coats of spray paint would go a long way toward improving the aesthetics. Just don’t spend too much time playing Overwatch, [AbyssalUnderlord].
If you like DIY portable setups, check this Transformers-themed portable workbench, or our Hacklet all about portable work stations and toolboxes.
Today’s computers are unimaginably complex, and so complicated it’s nearly impossible for anyone to comprehend everything a CPU can do in excruciating detail. It wasn’t always like this – the early CPUs of the 70s and 80s were relatively simple and can easily be recreated at the individual gate level. CPUs can be even simpler, as [Jack Eisenmann] demonstrates with a single instruction computer, the DUO Compact 2, made entirely out of 74-series logic chips and a bunch of memory.
[Jack] has a long history of building strange computers out of individual chips, including a TTL logic CPU and a significantly more complicated single instruction computer. The latest, though, is as simple as it gets. It’s just twenty chips, capable of calculating prime numbers, sorting strings, and everything else a computer is able to do.
With every one-instruction computer, there is the obvious question of what instruction this computer uses. For the DUO Compact 2 it’s a single instruction that accepts three arguments, A, B, and C. The instruction copies a byte from A to B, then jumps to the instruction at C. Is it even possible for a computer to add two numbers with this instruction? Yes, if you have massive look up tables stored in 2 Megabytes of Flash and 512 kB of RAM.
In the video below, [Jack] goes over how his tiny computer works and demonstrates prime number generation (it’s slow), string sorting (also slow), and displaying ’99 bottles of beer on the wall’ on the computer’s LCD. All the files to replicate this computer are available on [Jack]’s webpage, along with an emulator in case you don’t want to break out a breadboard for this one.
Continue reading “Designing A Single Instruction Computer”
[Robert Glaser] kept all his projects, all of them, from the 1960s to now. What results is a collection so pure we feel an historian should stop by his house, if anything, to investigate the long-term effects of the knack.
He starts with an opaque projector he built in the third grade, which puts it at 1963. Next is an, “idiot box,” which looks suspiciously like “the Internet”, but is actually a few relaxation oscillators lighting up neon bulbs. After that, the condition really sets in, but luckily he’s gone as far as to catalog them all chronologically.
We especially enjoyed the computer projects. It starts with his experiences with punch cards in high school. He would hand-write his code and then give it to the punch card ladies who would punch them out. Once a week, a school-bus would take the class to the county’s computer, and they’d get to run their code. In university he got to experience the onset of UNIX, C, and even used an analog computer for actual work.
There’s so much to read, and it’s all good. There’s a section on Ham radio, and a very interesting section on the start-up and eventual demise of a telecom business. Thanks to reader, [Itay Ramot], for the tip!
[Matikas] apparently forgets to lock the screen on his computer when he gets up to grab a coffee. And he apparently works with a bunch of sharks: “If you don’t [lock it], one of your colleagues will send email to the whole company that you invite them to get some beer (on your bill, of course).” Not saying we haven’t done similar, mind you. Anyway, forgetting to lock your screen in an office environment is serious business.
So [Matikas] built a great system that remotely types the keystrokes to lock his screen, or unlock it with his password. An off-the-shelf 433 MHz keyfob is connected to an Arduino micro that simulates a keyboard attached to his computer. It’s a simple system, but it’s a great effect. (See the video demo, below.)
Continue reading “Coolest, but Least Secure, Security Device”
[John Blankenbaker] did not invent the personal computer. Museums, computer historians, and authors have other realities in mind when they say [John]’s invention, the KENBAK-1, was the first electronic, commercially available computer that was not a kit, and available to the general population.
In a way, it’s almost to the KENBAK’s detriment that it is labelled the first personal computer. It was, after all, a computer from before the age of the microprocessor. It is possibly the simplest machine ever sold and an architecturally unique machine that has more in common with the ENIAC than any other machine built in the last thirty years..
The story of the creation of this ancient computer has never been told until now. [John], a surprisingly spry octogenarian, told the story of his career and the development of the first personal computer at the Vintage Computer Festival East last month. This is his story of not inventing the personal computer.
Continue reading “The Man Who Didn’t Invent The Personal Computer”