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.

source https://hackaday.com/2020/07/19/this-68k-board-is-about-as-simple-as-it-gets/

Motion capture is a technology used in many films, particularly the animated variety. It makes giving characters realistic movements a cinch, as they’re all based on those of a real person. [Checkered Bug] worked with a middle school group who were looking to get started, so he whipped up a capable rig on a budget.

The rig is based around a chest unit that connects out to several satellite units placed at points on the body. Each unit contains a Bosch IMU which is used to measure the acceleration and rotation of the user’s various body parts. The data is fed back to an Arduino Mega, where it’s then passed to a PC running Blender. Motion sequences can be recorded live in Blender, or saved to an SD card and imported later. Files are available on Github for those keen to recreate the project.

It’s a tidy setup that does good motion capture on a low budget. Such a rig would have been inordinately expensive back in the day, but can now be whipped up for just a few hundred dollars. We’ve seen other motion capture systems before, too. Video after the break.

source https://hackaday.com/2020/07/19/building-a-motion-capture-suit-on-the-cheap/

The prevalence of drones has made airborne photography much more widespread, especially among hobby photographers and videographers. However, drone photos aren’t without their problems. You have to deal with making the drone follow the shot which can be difficult unless you have a very expensive one. Worse, you can’t really fly a drone through heavily wooded or otherwise obstructed terrain.

[Makesome’s] friend faced these issues and wanted to buy a cable cam — a mount for the camera that could go back and forth on a cable strung between two trees or other structures. Instead of a design from scratch, they decided to cannibalize a cheap RC car along with an HP printer and the effect — as you can see in the video below — is pretty good.

Repurposing toys is an honored tradition and, after all, what do you need but a motor that goes forward and reverses? We can’t help but notice though that toy hacking is much easier now that you can 3D print custom widgets to connect everything together.

The video isn’t really a tutorial because you will likely start with a different car and have different needs. But there’s enough info there to give you some ideas. It looks like the car’s contribution was mostly the RF remote control portions. There’s also an Arduino and some drive electronics to take care of the motor donated by an old printer.

If you prefer to slide your camera on a rail, we’ve seen many setups for that. Or try a camera dolly on wheels.

source https://hackaday.com/2020/07/19/rc-car-becomes-cable-cam/

In June, many owners of Samsung Blu Ray players found that their devices were no longer usable. Stuck in a boot loop, speculation was rife as to the cause of the issue. Now it seems that the issue has become clear – a badly formatted XML file may be responsible for the problems (via The Register).

The problem stems from the logging system that stores user data and passes it back to Samsung over the Internet. Which data is logged and sent back is managed by an XML file which contains the policy settings that control this behaviour. According to a source known only as “Gary”, the XML file posted on Samsung’s servers on June 18 featured a malformed list element. This caused a crash in the player’s main software routine, leading the player to reboot.

The failure was exacerbated by the fact that the XML file is parsed very early in the boot sequence, even before checking for firmware updates or a new XML file. This has prevented Samsung from rolling out an update or fix over the air, and is why the player gets stuck in a loop of continuous reboots.

Reportedly, the file can be found at this URL, though is now an updated version that shouldn’t brick players. Samsung have had to resort to a mail-in repair scheme, wherein technicians with service tools can manually remove the offending XML file from the player’s storage, allowing it to boot cleanly once again. While this shows our initial assumptions were off the mark, we’re glad to see a solution to the problem, albeit one that requires a lot of messing around.

[Thanks to broeckelmaier for the tip!]

source https://hackaday.com/2020/07/19/the-real-story-how-samsung-blu-ray-players-were-bricked/

Anyone old enough to fondly recall the “bleep-burp-rattle” sequence of sounds of a modem negotiating a connection over a phone line probably also remembers the simple “tin-can telephone” experiment, where a taut string transmits sound vibrations from the bottom of one tin can to another.  This tin can modem experiment puts both of those experiences together in a single project.

As [Mike Kohn] notes, this project was harder than it would seem that it should be. He actually had a much harder time getting the tin can phone part of the project optimized than getting the electronics sorted out, resulting in multiple tries with everything from the canonical tin cans to paper coffee cups before eventually settling on a pair of cardboard nut cans, the kinds with the metal bottoms. Linked together with a length of kite string — dental floss didn’t work — [Mike] added a transmitter on one end and a receiver on the other.

The transmitter used an ATtiny 2313 and everyone’s favorite audio amplifier, the LM386, while the receiver sported an electret mike preamp board, an LM566 tone decoder, and an MSP430 microcontroller. The modulation scheme was as simple as possible — a 400 Hz tone whose length varies whether it’s a one or a zero, or a stop or start bit. Connected to a pair of terminal programs, [Mike] was able to send his name over the wire string at what he calculates to be six or seven baud.

This project has all the hallmarks of lockdown boredom, but we don’t care because it’s good fun and a great learning opportunity, particularly for the young ones. There’s plenty of room for optimization, too — maybe it could even get fast enough for the Hackaday Retro 300-baud challenge.

source https://hackaday.com/2020/07/18/a-tin-can-modem-just-for-fun/