The article Home Computers Behind the Iron Curtain sparked a lot of interest, which made me very happy. Therefore, I decided to introduce more computer curiosities from the Iron Curtain period, especially from the former Czechoslovakia (CSSR).
As I mentioned in the previous article, the lack of spare parts, literature and technology in Czechoslovakia forced geeks to solve it themselves: by improvisation and what we would today call “hacking.” Hobbyist projects of one person or a small party was eventually taken over by a state-owned enterprise, which then began to manufacture and deliver to stores with some minor modifications. These projects most often involved a variety of peripherals that could only be found in the Czechoslovakia with great difficulty.
Much like the production of components, the production of peripherals was also distributed throughout the eastern block so that each country was specializing in certain types of peripherals. For example, East Germany produced matrix printers, and Bulgaria made floppy disks drives. This meant industrial enterprises had to wait for vital computer parts, because the production in another country was not sufficient to cover even the local requirements, let alone the home user.
Continue reading “Peripherals Behind The Iron Curtain”
We’ve all seen Daft Punk helmet builds, but [George’s] project is a homemade LED helmet that takes no shortcuts and packs the visor full of hundreds of individual lights. He started with a prototype that uses a PIC 18F4580 microcontroller connected to a MAX7221 LED driver, which gave him control over some dot matrix displays to test the wiring and sample script. He then used this prototype setup to develop a scrolling text function.
With testing complete, [George] wired hundreds of LEDs into 8×8 block sections, using a cardboard jig to keep everything straight. He could have stopped there, but [George] took the build further, adding an LCD display and a 7-segment clock module to the inside of the helmet, in view of the wearer. The clock displays the helmet’s current beats per minute rate, while the LCD shows the content being displayed (pattern, text / Pacman, stripes). It’s possible to see out between the bottom of the display and the chin of the helmet. If you need better visibility we’d recommend a bike helmet matrix that isn’t as dense.
You can watch a video of the helmet running different patterns below. (Warning: music). When you’re done with that, why not LED all the things: from Infinity Mirrors to LED Sneakers.
Continue reading “Homemade LED helmet”
Earlier this month, [Kenneth] picked up an old dot matrix printer at the Silicon Valley Flea Market and subsequently found two cases of tractor feed printer paper. It’s a marriage made in heaven for a dot matrix twitter printer.
[Kenneth] used a BeagleBone – a tiny single board computer running Linux – to connect to the Internet and fetch any new tweets mentioning KWF every minute or so. The BeagleBone spits out these tweets over the USB port which is connected to the ancient printer by means of a cheap adapter cable.
Interestingly, [Kenneth] wrote the code for this project as a shell script. A lot of effort went into scrubbing the input of any escape characters, but he still implores his admirers to not attempt to break his project.
In case you’re wondering, at couple Twitter accounts announced this post’s headline to the Twitterverse when this story was published. This should have immediately sent [Kenneth]’s printer into motion, recording that harsh mistress that is sending a build log of a Twitter connected device into Hackaday.
After the break you can see [Kenneth]’s demo. Be sure to share this post on Twitter!
A while back, [DragonMinded] picked up a bunch of old arcade and pinball parts from a guy on Craigslist. These parts sat around for a while until a really neat plasma dot matrix display was found in the corner of a box in his garage. Doing the only reasonable thing, [DragonMinded] figured out how to interface this ancient display with a microcontroller.
After extensive Internet research on his display, [DragonMinded] could only find a one page datasheet for his APD-128G064A-1 display. Luckily, this datasheet had voltage requirements, and since the display only had six input pins he could probe the circuit to see what goes where.
After generating a crude schematic, [DragonMinded] prototyped a driver circuit with an Arduino. When the function of each pin was discovered, the Arduino libraries were discarded and replaced with raw register access.
It was a fair amount of work, but [DragonMinded] eventually got to the point where he could draw anything he wanted on the screen. Next on the to-do list is turning it into a terminal or Twitter machine, as with all good display hacks.
What uses a fire extinguisher, a bike pump, and provides hours of probation, community service, and possibly jail time? If you said an automatic graffiti writer you’re correct! [Olivier van Herpt] calls this little job the Time Writer. We call it defacing property… but tomato, tomahto.
Details are a bit scarce, but you get a fine overview of the system from the video after the break. [Olivier] tagged the post as Arduino; it’s obviously running the dot matrix printer made up of seven solenoid valves on a metal rod. These are fed ink via a tube connected to a fire extinguisher which serves as the reservoir. The bike pump is used to pressurize the enclosure so that a pump isn’t necessary when out and about.
Obviously you shouldn’t try this at home, but let’s talk about possible improvements as an academic exercise. First off the mix of the ink/paint needs to be reigned in to get rid of the dripping. We’d also like to see the inclusion of some proper spray can nozzles to tidy up the results. That, paired with an IMU board should be able to smooth out the printed designs.
This might make an interesting add-on to that rainbow graffiti writer.
Continue reading “Weapon of mass graffiti”
[Kevin] sent in his almost finished open source dot matrix clock. Sporting a hefty 40 x 16 display powered by a PIC 18F he has complete pixel by pixel control of the graphics. Combined with with a triple buffer he is at least able to output 15fps, with planned 30fps. While this has great potential for a clock, what about going further? Twitter updates, chat messages, weather updates, the current airspeed velocity of an unladen swallow; it will be tough to beat the competition without some more features. Either way, its an awesome project and we can’t wait to see it completed.
Ok, there aren’t any usefull applications we can think of for this one, but we want one really badly. This is a combination of a miniPOV, some UV LEDs, a CNC rig, and some glow in the dark paper. The Ghost matrix works similar to a dot matrix printer where it flashes the UV light to activate the paper. The final effect is very nice. Great job on this one.
[via Laughing Squid]