The Tiniest Working 68K System

January 28, 2018 by Jenny List 36 Comments

68000 microprocessors appeared in the earliest Apple Macintoshes, the Commodore Amiga and Atari ST, and the Sega Genesis/Mega Drive among other familiar systems. If you were alive during the 16-bit era, there is a good chance that you will have owned a Motorola 68000 or one of its derivatives in a computer or game console. By the end of the 1990s it was clear that the 68K line had had its day on the desktop, but a new life for it at the consumer level was found in the PDA market. The first Motorola Dragonball was a 68000 series system-on-chip, and it was a few of these in a BGA package that [Plasmode] had in stock after ordering them in error believing them to be in a different package.

The Dragonball 68328 has an interesting bootstrap mode allowing it to run with no external ROM or RAM, and with only a serial connection to the outside world. Recognising this as having the potential for the smallest possible 68K system, he proceeded to make it happen with some impressive soldering direct to the solder balls of an upturned BGA package.

On a piece of PCB material are simply the 68328, a 32.768kHz crystal and capacitors, a MAX232 circuit for an RS232 serial connection, a reset button, and a power regulator. Using the Motorola DOS debug software which is still available for download after all these years, he was able to connect to his tiny 68K computer and run code. It’s not entirely useful, but of all the possible 68K configurations it has to be the smallest.

This isn’t the first minimal computer using only a processor chip and serial link, in the past we’ve shown you a PDP-11 in the same vein.

A Talking Clock For The 21st Century

January 27, 2018 by Jenny List 24 Comments

The Talking Clock service is disappearing, and it’s quite possible that few of you will be aware of its passing. One of the staples of twentieth-century technology, the Talking Clock service was the only universally consumer-available source of accurate time information away from hourly radio time signals in the days before cheap radio-controlled clocks, or GPS. You’d dial (on a real dial, naturally!) a telephone number, to be greeted with a recorded voice telling you what the time would be at the following beep. Clocks were set, phone companies made a packet, and everybody was happy with their high-tech audio horology.

[Nick Sayer] used the USNO Master Clock telephone feed to see in the New Year, but had to make do with a voice from another time zone. It seems that there are no services remaining that provide one in Pacific time. His solution to the problem for a future year? Make his own Talking Clock, one that derives its time reference from GPS.

At its heart is a SkyTraq Venus838LPx miniature GPS module coupled to an ATMega32E5 microcontroller. The speech comes in the form of pre-recorded samples stored on an SD card. There is a small on-board amplifier to drive a single speaker. For extreme authenticity perhaps it could be attached to a GSM mobile phone module to provide a dial-up service, but he’s got everything he needs for a New Years Eve.

Want to hear what that that bit of nostalgia sounded like? Check out the quick clip below. As for modern replacements, we’ve had at least one talking clock here in the past, but not one using GPS.

Continue reading “A Talking Clock For The 21st Century” →

Drink Lots Of Beer To Raise Your Monopole

January 26, 2018 by Jenny List 19 Comments

When we published a piece about an ADS-B antenna using a Coke can as a groundplane, Hackaday reader [2ftg] got in contact with us about something with a bit more… stature.

A monopole groundplane antenna is a single vertical conductor mounted on an insulator and rising up above a conductive groundplane. In radio terms the groundplane is supposed to look as something of a mirror, to provide a reflection of what would come from the other half of a dipole were there to be two conductors. You can use anything conductive as your monopole, a piece of wire, (in radio amateur humour) a piece of wet string, or even beer cans. “Beer cans?” you ask incredulously, expecting this to be another joke. Yes, beer cans, and [2ftg] has been good enough to supply us with a few examples. The first is a 57-foot stack of them welded together in the 1950s for use on the 80 metre band ( we suspect steel cans may have been more common than aluminum back then), the second is a more modest erection for the 2 metre band, and the final one consists of photographs only of an HF version that looks a little wavy and whose cans are a little less beery.

The reporting in the 1950s piece is rather cheesy, but does give a reasonable description of it requiring welding rods as reinforcement. It also gives evidence of the antenna’s effectiveness, showing that it could work the world. Hardly surprising, given that a decent monopole is a decent monopole no matter how many pints of ale you have dispatched in its making.

The Coke can ADSB can be seen in all its glory here, and if all this amateur radio business sounds interesting, here’s an introduction.

Beer cans picture: Visitor7 [CC BY-SA 3.0].

This Home-Made PDA Is A Work Of Art

January 24, 2018 by Jenny List 39 Comments

There was a time, back in the 1990s, when a PDA, or Personal Digital Assistant, was the height of mobile computing sophistication. These little hand-held touch-screen devices had no Internet connection, but had preloaded software to manage such things as your calendar and your contacts. [Brtnst] was introduced to PDAs through a Palm IIIc and fell in love with the idea, but became disillusioned with the Palm for its closed nature and lack of available software a couple of decades later.

His solution might have been to follow the herd and use a smartphone, but he went instead for the unconventional and produced his own PDA. And after a few prototypes, he’s come up with rather a well-executed take on the ’90s object of desire. Taking an ARM microcontroller board and a commodity resistive touchscreen, he’s clad them in a 3D-printed PDA case and produced his own software stack. He’s not prepared to release it just yet as he’s ashamed of some of its internal messiness, but lets hope that changes with time.

What this project shows is how it is now so much easier to make near commercial quality one-off projects from scratch. Accessible 3D printing has become so commonplace as to be mundane in our community, but it’s worth remembering just how much of a game-changer it has been.

To see the device in action, take a look at the video below the break.

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Someone’s Made The Laptop Clive Sinclair Never Built

January 21, 2018 by Jenny List 42 Comments

The Sinclair ZX Spectrum was one of the big players in the 8-bit home computing scene of the 1980s, and decades later is sports one of the most active of all the retrocomputing communities. There is a thriving demo scene on the platform, there are new games being released, and there is even new Spectrum hardware coming to market.

One of the most interesting pieces of hardware is the ZX Spectrum Next, a Spectrum motherboard with the original hardware and many enhancements implemented on an FPGA. It has an array of modern interfaces, a megabyte of RAM compared to the 48k of the most common original, and a port allowing the connection of a Raspberry Pi Zero for off-board processing. Coupled with a rather attractive case from the designer of the original Sinclair model, and it has become something of an object of desire. But it’s still an all-in-one a desktop unit like the original, they haven’t made a portable. [Dan Birch has changed all that, with his extremely well designed Spectrum Next laptop.

He started with a beautiful CAD design for a case redolent of the 1990s HP Omnbook style of laptop, but with some Spectrum Next styling cues. This was sent to Shapeways for printing, and came back looking particularly well-built. Into the case went an LCD panel and controller for the Next’s HDMI port, a Raspberry Pi, a USB hub, a USB to PS/2 converter, and a slimline USB keyboard. Unfortunately there does not seem to be a battery included, though we’re sure that with a bit of ingenuity some space could be found for one.

The result is about as good a Spectrum laptop as it might be possible to create, and certainly as good as what might have been made by Sinclair or Amstrad had somehow the 8-bit micro survived into an alternative fantasy version of the 1990s with market conditions to put it into the form factor of a high-end compact laptop. The case design would do any home-made laptop design proud as a basis, we can only urge him to consider releasing some files.

There is a video of the machine in action, which we’ve placed below the break.

Continue reading “Someone’s Made The Laptop Clive Sinclair Never Built” →

Weaving With Light: An OLED Fibre Fabric Display

January 21, 2018 by Jenny List 11 Comments

If you think of wearable electronic projects, in many cases what may come to mind are the use of addressable LEDs, perhaps on strips or on sewable PCBs like the Neopixel and similar products. They make an attractive twinkling fashion show, but there remains a feeling that in many cases once you have seen one project, you have seen them all.

So if you are tiring of static sewable LED projects and would like to look forward to something altogether more exciting, take a look at some bleeding-edge research from a team at KAIST, the Korean Advanced Institute of Science & Technology. They have created OLED fibres and woven them into fabric in a way that appears such that they can be lit at individual points to create addressable pixels. In this way there is potential for fabrics that incorporate entire LED displays within their construction rather than in which they serve as a substrate.

The especially interesting feature of the OLED fibres from the KAIST team is that their process does not require any high temperatures, meaning that a whole range of everyday textile fibres can be used as substrates for OLEDs. The results are durable and do not lose OLED performance under tension, meaning that there is the possibility of their becoming practical fabrics for use in garments.

While this technology is a little way away from a piece of clothing you might buy from a store, the fact that it does not rely on special processes during weaving means that when the fibres become commercially available we are likely to see their speedy adoption. Meanwhile you can buy conductive fabric, but you might have to take a multimeter to the store to find it.

Via EENewsLED, and thank you [Carl] for the tip.

Color Organ Dress, A Wearable With Audio Feedback

January 20, 2018 by Jenny List 5 Comments

There is a huge amount of interest among our community in wearable electronics, but it is fair to say that it is a technology that has a way to go at our level in terms of its application. Some twinkly LEDs are all very well, but unless you have the arrived-on-a-spaceship-from-the-future aesthetic of someone like [Naomi Wu] to carry them off they get old rather quickly.

What the sew-on LED sector of wearable electronics is waiting for are some applications, wearable lights that do something rather than just look pretty. And [Moko] has a project that takes them in that direction, with her color organ dress, a garment whose LEDs react to ambient sound with the aid of a MEMS microphone and an Adafruit Gemma M0 microcontroller board. The LEDs form a color wheel which rotates, and stops at a point proportional to the sound level at the time.

The write-up is an interesting one, going into a little detail as it does in the images on the construction of an electronically-enhanced piece of clothing. Wiring everything up is one thing, but there are other considerations such as the incorporation of extra panels to protect them from mechanical stress, and from sweat. From a dressmaker’s perspective it’s a well constructed garment in its own right with an attractive PCB-style pattern (Where did she get that fabric? Or did she print it herself?) and it appears that she’s the fortunate owner of a serger (overlocker).

Well-assembled clothing has made it here before, for example an impressive jellyfish skirt or this laser-cut arcsin dress. And should you wish to make a garment for your next wearable project, you’ll be sure to need a well-stocked textile bench.