Hackaday Retro Edition And Retro Roundup

January 25, 2014 by Brian Benchoff 24 Comments

Retro-Roundup

About a year and a half ago, We launched the Hackaday retro edition, a small off-shoot of the main edition that is written in pure HTML, with no Javascript or any other Web 2.0 cruft. It’s designed so you can load this edition on any computer, from an Apple Newton to a Commodore 64. And people have done just that.

After a long period of neglect, we’re re-launching the retro edition with a new feature: every hour or so, five random Hackaday pages, going all the way back to the very first post will show up on the retro site. Yes, this was a feature we originally planned for the retro site, but now Hackaday has awesome devs working behind the scenes. I mean, they can set up a cron job! It’s amazing!

As always, you’re more than welcome to load our retro site with any vintage hardware, take a picture, and send it in. Odds are, we’ll plaster it up in one of these semi-frequent retro roundup posts.

No retro roundup post would be complete without a few examples of people loading the retro edition on old hardware. You can check a few out after the break.

Continue reading “Hackaday Retro Edition And Retro Roundup” →

Minicomputers On Microcontrollers

January 24, 2014 by Brian Benchoff 28 Comments

Developed in the very late 60s and through the 70s, the PDP-11 series of minicomputers was quite possibly the single most important computer ever created. The first widely distributed versions of Unix and C were developed on the PDP-11, and it’s hardware influence can be found in everything from the Motorola 68000 to the MSP430.

When [Dave Cheney] saw the recent 8086 simulator written in 4kB of C code, he realized simulating entire computer systems doesn’t actually require a whole lot of resources outside a big chunk of memory. Armed with an Arduino Mega clone, he set out on one of the coolest projects we’ve seen in a while: simulating a PDP-11 on an AVR.

[Dave] used an ATMega2560-powered Arduino Mega clone with an Ethernet module for the hardware of this build. Attached to it is a shield filled up with a pair of RAM chips that expand relatively limited amount of RAM on the ‘Mega.

So far, [Dave] has his simulated system booting Unix V6 off an SD card. For PDP-11 storage, he’s also simulating an RK05 disk drive, a massive 14 inch platter containing 2.5 Megabytes of data. Compared to the original PDP-11/40, [Dave] estimates his machine is about 10 times slower. Still, an original 11/40 system fills multiple server racks, and the most common installations consume several kilowatts of power. The Arduino Mega can fit in a pocket and can be powered over USB.

Future developments for this system include improving the accuracy of the simulator, running more advanced operating systems and the DEC diagnostic programs, and possibly speeding up the simulation. We’d suggest adding some switches and blinkenlights on an additional shield, but that’s just us.

All the code can be found on [Dave]’s git, with a description of his SPI RAM shield coming shortly.

Sega Master System On A STM32 Development Board

January 14, 2014 by Eric Evenchick 19 Comments

Some hackers have managed to convert an STM32 development into a Sega Master System emulator. This means Sonic the Hedgehog running on an ARM Cortex-M4.

This hack has a number of parts. First, [Alessandro Rocchegiani] showed off a video of his Sega Master System emulator running on the STM32F429 Discovery development board. This first version used the on board 2.4″ TFT LCD screen.

[Fabrice] was working with this STM32 Discovery board already. He had developed an expansion board that added a number of features to the development kit, including an R-2R DAC for video output. When [Fabrice] found out about the Sega Master System emulator, he worked with [Alessandro] and his son [Fabrizio] to get VGA output working. They also added support for the Wii controller using [Fabrice]’s Wii library. The result is a Sega Master System emulator with VGA output at 640 x 480, with 16 bit color and Wii controller support.

You can watch a video of both the LCD and VGA versions of the hack after the break.

Continue reading “Sega Master System On A STM32 Development Board” →

A DiskVaccuum For Obsolete Disk Formats

January 10, 2014 by Brian Benchoff 24 Comments

drive

[Jim] has a box of disks for a very old Compucolor II computer, and with bit rot slowly setting in he figured it might be time to dump all those disks to a more permanent format. After reviewing the existing tools to read these disks, he decided to build his own floppy disk interface that he calls the DiskVaccuum.

The DiskVaccuum is based on a Papilio Pro FPGA board and a few chips worth of level conversion. The FPGA is able to read bits and move the head of the disk with ease, saving everything to the drive of a much more modern computer.

On the USB side of the Papilio board, [Jim] wrote a shell of sorts in Python to capture tracks on the disk, read out the track listing, save an image file, and do all the things a proper DOS should. Right now the project is only for the Compucolor II disk drive, but [Jim] played around with KiCAD enough to create a Papilio-to-disk-drive interface board with connectors for most of the disk drives of this particular vintage. The hope is to generalize the hardware and software to read disks for other systems, including those with 8-inch drives.

[Jim] put up a video describing the hardware and demoing his Python capture utility. You can check that out below.

Continue reading “A DiskVaccuum For Obsolete Disk Formats” →

Drawing With Legos

January 10, 2014 by Marsh 82 Comments

WritingMachineFrontLarge

There are a number of elaborate Lego creations out there, but you probably haven’t seen something quite like [Andrew Carol’s] Lego drawing machine. He drew inspiration from the film Hugo and from automata of the 1800’s, specifically [Jaquet-Droz]’s Draughtsman, which we featured in a Retrotechtacular article not too long ago.

[Andrew’s] hand-cranked creation is divided into three components: a plotter, an “encoded pen stroke program”—which stores messages in links of pieces—and a reader that translates the links into pen strokes. The plotter moves the pen in the Y axis and moves the paper in the X to mark on the page, and also has a simple lift mechanism that temporarily raises the pen on the Z axis to interrupt pen strokes between letters (or drawings).

[Andrew] describes the chain reader by comparing it to a film projector, feeding the message through the mechanism. Although you won’t find a detailed how-to guide explaining the devices’ inner-workings on his site, there are some clues describing basic components and a couple of videos, both of which are embedded below.

Continue reading “Drawing With Legos” →

Acoustic Delay Line Memory

January 7, 2014 by Brian Benchoff 48 Comments

Back in the olden days when computers were both analog and digital, making RAM was actually very hard. Without transistors, the only purely electronic means of building a memory system was vacuum tubes; It could have been done, but for any appreciable amount of RAM means an insane amount of tubes, power, and high failure rates.

One of the solutions for early RAM was something called a delay line. This device used ultrasonic transducers to send a pulse through a medium (usually mercury filled tubes heated to 40°C) and reads it out at the other end. The time between the pulse being sent and received is just enough to serve as a very large, small capacity RAM.

Heated tubes filled with hundreds of pounds of mercury isn’t something you’d want sitting around for a simple electronics project. You can, however, build one out of a Radio Shack Electronics Learning Lab, a speaker, and a microphone.

[Joe] designed his delay line using an op-amp to amplify the train of acoustic pulses traveling through the air. A compactor picks up these pulses and sends them into a flip-flop. A decade counter and oscillator provide the timing of the pulses and a way to put each bit in the delay line. When a button on the electronics lab is pressed, a ‘tick’ is sent into the speaker where it travels across [Joe]’s basement, into the microphone, and back into the circuit.

The entire setup is able to store ten bits of information in the air, with the data conveniently visualized on an oscilloscope. It’s not a practical way to store data in any way, shape, or form, but it is an interesting peek into the world before digital everything.

Video below.

Continue reading “Acoustic Delay Line Memory” →

Overhauling An IC Programmer

January 6, 2014 by Eric Evenchick 16 Comments

[NeXT] needed an EPROM programmer to work with chips from vintage computers. Starting with a low cost programmer, he built this custom IC programmer to handle all of his programming needs.

The device is based on the Willem 5.0e programmer. [NeXT] was not satisfied with the device, noting that it had to be carefully isolated from metal surfaces during use and required setting many annoying jumpers.

To solve these problems, he started off by dismantling the programmer. The IC sockets were moved to a daughter board, which could be mounted cleanly into the metal enclosure. Replacing the jumpers was a bit more complicated, a combination of toggle and rotary switches were chosen to make changing settings easier.

Soldering the boards together looks like it was not an easy task, with 200 solder joints needed to connect the sockets and switches. After debugging some shorts and dead connections, [NeXT] managed to finish the 1.5 year project right before his Christmas deadline.