Capacitive Sensing And Old IBM Keyboards

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The pen is mightier than the sword, but the IBM Model M keyboard, properly applied, can knock teeth in. There are a few more IBM keyboards even better suited to blunt force trauma – the extremely vintage beam spring keyboards made for terminals and desktop publishers. Being so very old, there’s no easy way to connect these keyboards to a modern system, so when [xwhatsit] wanted to make his work, he needed to build his own controller.

The beam spring keyboards use capacitive switches, and with 122 keys, the usual method of reading capacitance – putting a capacitor in an oscillator – would be far too slow to be of any use in a keyboard. There is another method of reading capacitance: measuring the current going through the capacitive switch. This can easily be accomplished with an LM339 comparator.

[xwhatsit]‘s keyboard controller uses this capacitive sensing circuit to read the four rows of keys, with a few shift registers taking care of the columns. An ATMega32u2 is the brains of the outfit, running LUFA to translate the key presses to USB.

If you’re lucky enough to have one of these ancient keyboards, [xwhatsit] is selling a few over on the usual mechanical keyboard forums. There’s also a controller for the Model F keyboard using the same basic circuit. If you need one just drop him a line or grab the gerbers and roll your own.

 

 

Retrotechtacular: Once Upon A Punched Card

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Ah, the heady days of the early 60s, where companies gave their salesmen exquisitely produced documentaries, filled with incidental music written by the best composers of the era, and a voice actor that is so unabashedly ordinary you would swear you’ve heard him a hundred times before. It’s a lot better than any PowerPoint presentation anyone could come up, and lucky for us, these 16mm films are preserved on YouTube for everyone to enjoy. This one was sent out to IBM sales reps pushing a strange technology called a ‘punched card’, a system so efficient it will save your company tens of thousands of dollars in just a few short years.

Like most explanations of what a punched card does, this IBM documercial begins with the history of the Jacquard loom that used punched cards for storing patterns for textile weaving. In a rare bit of historical context befitting IBM, this film also covers the 1880 US census, an important part in the evolution of punched cards being used not as instructions for a loom, but data that could be tabulated and calculated.

The United States takes a census every ten years. The tenth census of 1880 took so long to compile into the data – seven years – it was feared the next census of 1890 wouldn’t be complete until the turn of the century. This problem was solved by [Herman Hollerith] and his system of encoding census data onto punched cards for tabulation. [Hollerith] would later go on to found the Tabulating Machine Company that would later merge with two other companies to form IBM. Isn’t it great that IBM chose to include that little nugget in their film.

As a point of interest, the film does contain a short pitch for IBM punched card writers, sorters, and calculators – the backbone of IBM’s medium to large size business sales. At the time this film was produced (1964) IBM was ready to announce the System/360, what would become the de facto mainframe for businesses of all sizes.  Yes, the /360 also used punched cards, but we wonder how many angry phone calls the sales reps received months after showing this film.

Laser Etching Brings New Life To An IBM Keyboard

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[Evan] was perusing his local thrift store when he found a beautiful IBM Model M 122-key keyboard made in 1987.

“This is my keyboard, there are many like it, but this one is mine.”

~The Typist’s Creed

In [Evan's] case, this might actually be the only one like it still in use today. An idea formed in his head. What if he took this ancient keyboard, gave it a USB driver, and customized the keys on a hardware level to do exactly what he wanted.

The first step was converting it to USB. He’s using a Teensy 2.0 mostly because it is super inexpensive, and its able to act as a USB HID device. In addition to wiring up the keyboard to the Teensy he’s also added foot pedals that connect via 1/8″ stereo plugs — these kind of act like extra mouse buttons, allowing him to scroll through galleries left to right, add page breaks, and other macros to increase efficiency.

[Read more...]

Building a More Nyan Planet

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In an effort to give salespeople something impressive to hand out, IBM recently had a bunch of very cool promotional materials printed up. It’s basically a greeting card-sized cardboard folder with a bit of text, an LCD screen, buttons, battery and display controller. This video in print device is meant to display how IBM is building a smarter planet, but [Cookie] and [Stitch] over at the Hack42 hackerspace in The Netherlands decided Nyan Cat would be a much better use of this free, portable video player. (Google translationUPDATE: Site has gone down. Here’s the Google Cache but you’ll need a browser like Chrome that can do the translation for you (we can’t figure out how to link a translation of cache).

This video card uses tech licensed from Americhip, a company that has been putting video in magazines for a few years now. By connecting the USB charging port up to his computer, the guys were able to switch the device over to USB mode where the actual video files could be read and rewritten.

By encoding a few videos to match the format of what was on the card – including some old IBM promotional material by [Jim Henson] – the team were able to get videos playing on a hackable flyer. Very cool, and if you can get your hands on some sales brochures, a free source of tiny displays.

Converting an IBM PCjr joystick to USB

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Seeing this IBM joystick again really brings back memories. But it can be used on a modern system thanks to this USB conversion project.

This particular model had a connector which is foreign to us. It looks like a boxy USB-A plug, but has an eight-pin sockets which looks like it’s 0.1″ pitch. You could try to make your own male connector using a dual-row pin header, but [Gruso] just went ahead and lopped off the end of the cable. He managed to dig up the pin-out for the device and found that it could be wired up to a gameport — the connector being the only real difference. He gutted a USB gameport adapter, removing the DB15 connector and soldering directly to the board. The boxy old peripheral has just enough room to house that PCB.

If you’re looking for a few more details than this build album provides check out [Gruso's] comments in the Reddit thread.

$250,000 hard drive teardown

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Have you ever seen hard drive platters this big before? Of course you haven’t, the cost of this unit is way beyond your pay grade. But now that it’s decades old we get a chance to post around inside this beast. [Dave Jones] — who we haven’t seen around these parts in far too long — takes a look inside this $250,000 storage device.

In this episode of the EEVblog [Dave] is tearing down a late 1980’s IBM hard drive. This an IBM 3390. It stores either 1.78GB or 3.78GB. These days we’d never use a mechanical drive for that little storage as flash memory is so much cheaper. But this was cutting edge for servers of the day. And that’s why you’d pay a quarter of a million dollars for the thing.

[Dave] does what he’s known for in the video after the break. He energetically pours over every aspect of the hardware discussing function and design choices as he goes.

[Read more...]

God’s own keyboard, now with Bluetooth

For decades a thunderous roar rose from the bowels of IBM keyboards like the animus of angry and forgotten gods. These keyboards have fallen silent of late, due only to incompatibility with newer hardware. Now, Model Ms have been given a reprieve from landfills or recycling centers because of the work of [wulax] of geekhack and his Model M Bluetooth controller board.

[Read more...]

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