SBC

50 Articles

MC68k SBC with a monitor, keyboard and mouse

Motorola 68000 SBC Runs Again With A Raspberry Pi On Top

August 31, 2021 by 30 Comments

Single-board computers have been around a long time: today you might be using a Raspberry Pi, an Arduino, or an ESP32, but three decades ago you might find yourself programming a KIM-1, an Intel SDK-85, or a Motorola 68000 Educational Computer Board. These kind of boards were usually made by processor manufacturers to show off their latest chips and to train engineers who might use these chips in their designs.

[Adam Podstawczyński] found himself trying to operate one of these Motorola ECBs from 1981. This board contains a 68000 CPU (as used in several Macintoshes and Amigas), 32 kB of RAM, and a ROM program called TUTOR. Lacking any keyboard or monitor connections, the only way to communicate with this system is a pair of serial ports. [Adam] decided to make the board more accessible by adding a Raspberry Pi extended with an RS232 Hat. This add-on board comes with two serial ports supporting the +/- 12 V signal levels used in older equipment.

It took several hours of experimenting, debugging, and reading the extensive ECB documentation to set up a reliable connection; as it turns out, the serial ports can operate in different modes depending on the state of the handshake lines. When the Pi’s serial ports were finally set up in the right mode, the old computer started to respond to commands entered in the terminal window. The audio interface, meant for recording programs on tape, proved more difficult to operate reliably, possibly due to deteriorating capacitors. This was not a great issue, because the ECB’s second serial port could also be used to save and load programs directly into its memory.

With the serial connections working, [Adam] then turned to the aesthetics of his setup and decided to make a simple case out of laser-cut acrylic and metal spacers. Custom ribbon cables for the serial ports and an ATX break-out board for power connections completed the project, and the 40-year-old educational computer is now ready to educate its new owner on all the finer points of 68000 programming. In the video (embedded after the break) he shows the whole process of getting the ECB up and running.

[Adam] made a similarly clever setup with a Commodore 64 and an Arduino earlier. [Jeff Tranter] recreated a similar 68000 development board from scratch. And a few years ago we even featured our own custom-built 68k computer.

Continue reading “Motorola 68000 SBC Runs Again With A Raspberry Pi On Top” →

WiFiWart Boots Linux, Moves To Next Design Phase

July 26, 2021 by 12 Comments

Over the last few months we’ve been keeping an eye on WiFiWart, an ambitious project to develop a Linux single-board computer (SBC) small enough to fit inside a USB wall charger. Developer [Walker] says the goal is to create an easily concealable “drop box” for penetration testing, giving security researchers a valuable foothold inside a target network from which to preform reconnaissance or launch attacks. Of course, we don’t need to tell Hackaday readers that there’s plenty of other things you can do with such a tiny open hardware Linux SBC.

Today we’re happy to report that [Walker] has gotten the first version of the board booted into Linux, though as you might expect given a project of this complexity, there were a few bumps along the way. From the single missing resistor that caused U-Boot to throw up an error to the finer points of compiling the kernel for an embedded board, the latest blog post he’s written up about his progress provides fascinating insight into the little gotchas of bringing up a SBC from scratch.

Once the board was booted into Linux, [Walker] started testing out different aspects of the system. A memory benchmark confirmed the finicky DDR3 RAM was working as expected, and he was able to load the kernel modules for the dual RTL8188 interfaces and connect to a network. While the two WiFi modules are currently hanging off the board’s full-sized USB ports, they will eventually be integrated into the PCB.

Critically, this prototype board is also allowing [Walker] to get an idea of what the energy consumption of the final hardware might be. Even at full tilt, this larger board doesn’t go over 500 mA at 5 VDC; so if he designs the power supply with a maximum output of 1 A, he should have a nice safety margin. As mentioned in the previous post, the plan is currently to put the PSU on its own board, which will allow more effective use of the charger’s internal volume.

With the software and hardware now largely locked in, [Walker] says his attention will be turned towards getting everything small enough to fit into the final form factor. This will certainly be the most challenging aspect of the project, but with a growing community of hackers and engineers lending their expertise to the cause, we’re confident the WiFiWart will soon be a reality.

Putting An Ultra-Tiny Linux Board In A Phone Charger…Eventually

May 6, 2021 by 67 Comments

Among security professionals, a “drop box” is a device that can be covertly installed at a target location and phone home over the Internet, providing a back door into what might be an otherwise secure network. We’ve seen both commercial and DIY versions of this concept, and as you might expect, one of the main goals is to make the device look as inconspicuous as possible. Which is why [Walker] is hoping to build one into a standard USB wall charger.

This project is still in the early stages, but we like what we see so far. [Walker] aims to make this a 100% free and open source device, starting from the tools he’s using to produce the CAD files all the way up to the firmware the final hardware will run. With none of the currently available single-board computers (SBCs) meeting his list of requirements, the first step is to build a miniature Linux machine that’s got enough processing power to run useful security tools locally. Obviously such a board would be of great interest to the larger hacker and maker community.

The RTL8188CUS is likely to get integrated later on.

So far, [Walker] has decided on his primary components and is working on a larger development board before really going all-in on the miniaturization process. As of right now he’s planning on using the Allwinner A33 to power the board, a sub-$10 USD chipset most commonly seen in low-cost Android tablets.

The A33 boasts a quad-core Cortex-A7 clocked at 1.2 GHz, and offers USB, I2C, and SPI interfaces for expansion. It will be paired with 1 GB of DDR3 RAM, and an SD card to hold the operating system. Naturally a device like this will need WiFi, but until [Walker] can decide on which chip to use, the plan is to just use a USB wireless adapter. The Realtek RTL8188CUS is a strong contender, as the fact that it comes in both USB and module versions should make its eventual integration seamless.

Even if you’re not interested in the idea of hiding security appliances inside of everyday objects, this project is a fascinating glimpse into the process of creating your own custom Linux board. Whether you’re looking to put into a wall wart or a drone, it’s pretty incredible to think we’ve reached the point where an individual can spin up their own miniature SBC.

New Part Day: Hackboard 2, An X86 Single-Board Computer

December 22, 2020 by 121 Comments

From the old Gumstix boards to everyone’s favorite Raspberry Pi, common single-board computers (SBCs) have traditionally had at least one thing in common: an ARM processor. But that’s not to say hackers and makers haven’t been interested in an SBC with a proper x86 processor. Which is why the $99 Hackboard 2 is so exciting. With a modern x86 chip at the core it’s akin to a small footprint desktop motherboard, but with all the extra features that we’ve come to expect in a hacker-friendly SBC.

So what’s the big deal? In a word, compatibility. The fact that these diminutive computing devices shied away from the x86 architecture that most of us have been using on our desktops and laptops since the 1980s originally introduced software compatibility issues, but this was largely outweighed by the advantages of ARM. The latest NVIDIA Jetson is running on an ARM chip for the same reason the smartphone in your pocket is: they’re smaller, cheaper, and more energy efficient than x86.

However they’re rarely more powerful. Even the latest and greatest Raspberry Pi 4, often touted as a viable desktop replacement thanks to its quad core Cortex-A72, will get absolutely trounced by the pokiest of Intel’s Celeron CPUs. The performance gap is just too great. While the Pi can admirably handle most of the tasks the hacker community asks of it, there will always be a call for a board that puts raw processing power before anything else.

Sucking down nearly 40 watts at full tilt, the Hackboard 2 isn’t the SBC you’d want to use for a solar powered weather station. But if you’re putting together a set top box to play back video and run the occasional emulator, its Celeron N4020 processor and Intel UHD 600 GPU represent the most powerful combination available for a device of this size.

Continue reading “New Part Day: Hackboard 2, An X86 Single-Board Computer” →

Help, I’m Buried Alive By Tablets!

November 10, 2020 by 50 Comments

It’s fair to say that many Hackaday readers will have a propensity for hoarding electronic or tech junk. Who hasn’t hung on to something because “It might be useful someday”? Spare a thought for [Mike Drew], who in his own words is “buried alive by tablets”. In this case the tablets are Intel-based ones that look as though they ran one of those cut-down Windows versions, and they appear to be rejects from a repair shop processing customer returns that he saved from the dumpster. They are missing their backs, and not all of their screens work, but they amount to a tidy pile of Stuff That’s Too Good To Throw Away.

The exact spec is a 1.4 GHz quad-core Atom with 4 GB of RAM and 32 GB of Flash, and appear from the photos to have HDMI and USB 3 interfaces. Happily they run Linux Mint 20 so they have plenty of potential, but there is only so much that one person can do with them before running out of ideas. He tells us he’s made a Folding@Home cluster, but beyond that he’s open to suggestions. Depending on the age of the commenter no doubt he’ll be exhorted to run Beowulf or mine Bitcoin, but we’d suggest more sensible ideas.

So, what would you do with them? They lack the handy GPIO port of a Raspberry Pi, but with suitable USB peripherals could you use them in any lowish-power distributed node project where the popular SBC would be the usual choice? Perhaps something like WeeWX, or OpenEnergyMonitor. Or how about distributed mesh network nodes, after all there’s an x86 port of LibreMesh. It’s obvious that there’s plenty of potential to be found, so help [Mike] with his problematic bounty in the comments.

Odyssey Is A X86 Computer Packing An Arduino Along For The Trip

August 7, 2020 by 58 Comments

We love the simplicity of Arduino for focused tasks, we love how Raspberry Pi GPIO pins open a doorway to a wide world of peripherals, and we love the software ecosystem of Intel’s x86 instruction set. It’s great that some products manage to combine all of them together into a single compact package, and we welcome the recent addition of Seeed Studio’s Odyssey X86J4105.

[Ars Technica] recently looked one over and found it impressive from the perspective of a small networked computer, but they didn’t dig too deeply into the maker-friendly side of the product. We can look at the product documentation to see some interesting details. This board is larger than a Raspberry Pi, but its GPIO pins were laid out in exactly the same order as that on a Pi. Some HATs could plug right in, eliminating all the electrical integration leaving just the software issue of ARM vs x86. Tasks that are not suitable for CPU-controlled GPIO (such as generating reliable PWM) can be offloaded to an on-board Arduino-compatible microcontroller. It is built around the SAMD21 chip, similar to the Arduino MKR and Arduino Zero but the pinout does not appear to match any of the popular Arduino form factors.

The Odyssey is not the first x86 single board computer (SBC) to have GPIO pins and an onboard Arduino assistant. LattePanda for example has been executing that game plan (minus the Raspberry Pi pin layout) for the past few years. We’ve followed them since their Kickstarter origins and we’ve featured creative uses here and there. LattePanda’s current offerings are built around Intel CPUs ranging from Atom to Core m3. The Odyssey’s Celeron is roughly in the middle of that range, and the SAMD21 is more capable than the ATmega32U4 (Arduino Leonardo) on board a LattePanda. We always love seeing more options in a market for us to find the right tradeoff to match a given project, and we look forward to the epic journeys yet to come.

This 68k Board Is About As Simple As It Gets

July 19, 2020 by 15 Comments

For those of us who remember the Motorola 68000 microprocessor, it’s likely that a sizeable quantity of those memories will come in the form of a cream or grey box with a Commodore, Atari, or Apple logo on it These machines were the affordable creative workstations of their day, and under the hood were a tour de force of custom silicon and clever hardware design. We might, therefore, be excused for an association between 68000 based computers and complexity, but in reality, they are as straightforward to interface as the rest of the crop of late-1970s silicon. We can see it in [Matt Sarnoff]’s 68k-nano, about as simple a 68000-based single-board computer as it’s possible to get.

But for all its simplicity, this board is no slouch. It packs a megabyte of RAM, 64k of ROM, a 16550 UART, and an IDE interface for a CompactFlash card. There is also provision for a real-time clock module, through an interesting bit-banged SPI interface from the 16550’s control lines. There appears also to be a 50-pin expansion header.

Software-wise there is a ROM monitor that provides test and housekeeping functions, and which loads an executable from the card plugged into the IDE interface if there is one. This feature makes the board especially interesting, as it opens up the possibility of running a μClinux or similar kernel for a more fully-featured operating system.

The 68k doesn’t receive the attention here that some of its 8-bit contemporaries do, but it still appears from time to time. We’ve certainly featured at least one other 68000-based SBC in the past.

Thanks [Anton] for the tip.