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Sci-Fi Contest Prize Acquisition Issues — Oh Noes!

เสาร์, 03/29/2014 - 04:30

We spent quite a bit of time picking out prizes for the Sci-Fi contest. But wouldn’t you know it, literally the day after announcing the contest we cued up The Amp Hour and heard about a worldwide stock shortage (34:00) of BeagleBone Black boards. About a week later Adafruit ran an explanation of the issues. It became clear why we were having issues sources a quintet of boards so that we could deliver on our prize offer.

To further compound problems we a somewhat smaller issue sourcing Spark Core boards. We put in an order for a quintet of them when we posted the contest; at the time they were supposed to be shipping in late March, but now shipping estimates have been delayed to mid-April. Assuming no more delays these should be available by the time the contest ends at the end of April so keep your fingers crossed.

We have a good relationship with the folks over at Spark Core and can probably ask them to help us out if we do get in a bind. But we don’t think anyone is going to be able to deliver the BeagleBone Black boards (which we have on backorder) in time for the end of the contest. So here’s the deal: if you win and really want these exact boards in the prize package you select, we’re going to do what needs to be done to get it for you, eventually. If you don’t want to wait and there is a suitable alternative we’ll make that happen.

We wondered what people are doing if they don’t want to wait out these shortages. Are there any other open-hardware projects that are similar in price and functionality? Our gut says no (that’s why they’re in such high demand). But we’d love to hear about some alternatives. Let us know by leaving a comment below.


Filed under: contests

High Tech Convertible Desk Takes it Up a Notch

เสาร์, 03/29/2014 - 03:00

Standing desks seem to be all the rage today — but do you really want to commit fully to always standing? [Jeff Minton] didn’t, and when he found out how much convertible standing desks cost… he decided to make his own.

While brainstorming ways of accomplishing this he started browsing around eBay and found 18″ linear actuators for sale. They were $45 each, ran at 24V and could lift 600lbs each. Bingo. Actually, that’s kinda overkill…

He picked up a 24V power supply, an Arduino, and a 8-channel relay board.  The actuators are attached to the desk’s original legs using U-bolts which keep the legs straight and take the load of the desk. The untreated wood supports are there to reinforce the original desk, because they weren’t that sturdy in the first place.

It takes about a minute to fully actuate the legs, so while it’s not the prettiest nor the quickest solution — it does the trick and allows you to easily switch between standing and sitting.

Maybe he should try over-powering the actuators since the load is so small — could make it go a bit faster! And if you’re looking for a cheaper and more permanent solution, extended PVC legs do the trick too.


Filed under: home hacks

Hackaday’s Guide to Shanghai

เสาร์, 03/29/2014 - 00:01

We happened to be in Shanghai for Electronica trade fair this year and had a great time exploring heavy industrial gear and fantasizing about all the things we could do with it. However, we simply couldn’t ignore the fact that there was a whole city out there that we’re completely missing out on. So after less than a day of being surrounded by businesspeople and Miss Universe-dressed promoters, we decided to pack our bags and hit the streets.

The question was, where should we go? Finding interesting things in a city that keeps shapeshifting (the whole Shanghai skyline did not exist 20 years ago) can be a challenge. Fortunately, our friend [David Li] gave us a list:

  1. Xin Che Jian
  2. Jiu Xing market
  3. Beijing Lu electronic market
  4. Qiujiang Lu CNC/lasercut market
  5. DFRobot.com

…and off we were.

 

The Country’s First Hackerspace

Xin Che Jian is China’s first hackerspace, founded in 2010 by [David Li] and is currently based in Downtown Shanghai, Xuhui district. [David] is being modest in saying that the reason behind founding Xin Che Jian was not changing the world, but rather a simple fact that his wife wanted to throw out all the hardware junk he’s been piling up in the apartment and he needed a place for it. The reality is that this place has completely transformed the ‘Maker’ scene in China (term “Hacker” is rarely used on the other side of the Great Firewall). Inspired by this example, people have started opening up spaces in different cities and the whole thing is starting to reach scary proportions with government stepping in, creating “makerspaces” in schools and providing TV coverage.

We happened to be there on a rainy Wednesday night, and the whole place had an irresistible Bladerunner feel to it. Walls of cardboard boxes, hydroponics tent, tons of electronics and all sorts of people ranging from local makers to expat “new media” artists. The night we visited was “open night” and we got to hear a lot of interesting and diverse talks. Talk topics had a very wide range. One discussed using Max/MSP to generate sound corresponding to the time lapse camera recordings of the space. Another slightly bizarre demonstration outlined the importance of insulation when dealing with high voltages, which among other things, included “spark frying” of something that moves.

Shopping for Electronics

Next stop was Beijing Lu electronics market. This one is a dream — a five-floor superstore exclusively selling electronics components. It’s a farmer’s market for silicon. We have learned that a lot of these shops are actually brick-and-mortar fronts for stores on TaoBao, but here you can buy things first hand, with a personal touch from “your guy”. If you happen to live in Shanghai, you can get components delivered the same day, pizza-style: by carrier on scooter.

Surrounding streets are even better. It’s where you can buy metal, plastic, get stuff cut, folded, CNC’d or spot-welded right on the curbside. Big blocks of steel, iron, aluminum all cut to order by artisans with decades of experience. For makers, artists and hackers this is where a lot of the real jewels lie. For an extra dystopian flavor, you can enjoy the fact that, among rows of such shops, you can find things like food stands, cleaners and grocery stores. You can get your aluminum cut in one shop and get your nails done nextdoor.

And now for something completely different..

Small Business Catering to Makers

DFRobot is something you would not ordinary expect in China. It’s offices look & feel like a proper Silicon Valley startup; it’s engineers are young, passionate and big on Open Hardware. They have great ideas and build beautifully designed products targeting the DIY community, educators and researchers. Their goal is “bringing back the joy of thinkering to daily life” – still a radical concept in China. If I were Adafruit or Sparkfun, I would watch out for these guys.

We got to hang around their office and saw a lot of great projects, but the experience we enjoyed most was in the 3D Printer room. We came into this room only to find a couple of dozen 3D printers, all printing bones! Some professor ordered a couple of hundred human bones for him to use in some kind of kinetic art installation. Weird.

For more in-depth look on Maker culture and it’s intersection with industry development in China, check out our attempt at serious investigative journalism in an interview with the fantastic [Silvia Lindtner], researcher at Fudan University.

 

 


Filed under: Featured

The Auto Parking Mecanum Robot

ศุกร์, 03/28/2014 - 21:01

A while back, Hackaday visited the Clark Magnet School in Glendale, California to sneak a peek on their STEM-focused curriculum, FIRST robotics club, awesome A/V classroom, and a shop that puts most hackerspaces to shame. We saw a few builds while we were there, but [Jack]‘s auto parking mecanum robot was in a class by itself. It deserves its own Hackaday post, and now that [Jack] is on Hackaday Projects, he’s sharing all the details.

The most impressive aspect of [Jack]‘s build is the mecanum wheels; the side plates for the wheels were designed by [Jack] himself and machined on his school’s Haas mill. When the plates came out of the mill they were flat, and each of the fifteen little tabs on the plates needed to be bent at a 45 degree angle. With a CNC jig and a lot of time on his hands, [Jack] bent the tabs for all eight plates.

In addition to the plates, the rollers were custom made from non-expandable polyurethane poured into a CNC milled mold. That’s a one-part mold; [Jack] needed to make sixty of these little parts, one at a time.

The electronics are built around an Arduino Mega communicating with a joystick via an XBee. [Jack] found the relays in the off-the-shelf motor board couldn’t handle the current, so he replaced them with much, much larger ones in a hack job we’d be proud to call our own handiwork. There’s also a little bit of code that allows this motorized cart to pull off the best parallel parking job anyone could ever wish for. You can see that and a few videos of the construction below.

 


Filed under: robots hacks

A Mini Op-Amp Based Line Following Robot

ศุกร์, 03/28/2014 - 18:01

There’s no denying it. Super small robots are just cool. [Pinomelean] has posted an Instructable on how to create a mini line following robot using only analog circuitry. This would make a great demo project to show your friends and family what you’ve been up to.

Analog circuitry can be used instead of a microcontroller for many different applications, and this is one of them. The circuit consists of two op-amps that amplify the output of two phototransistors, which control each motor. This circuit is super simple yet very effective. The mechanical system is also quite cool and well thought out. To keep things simple, the motors drive the wheel treads, rather than directly through an axle. After the build was completed, the device needed to be calibrated by turning potentiometers that control the gain of each op-amp. Once everything is balanced, the robot runs great! See it in action after the break.

While not the smallest line follower we have seen, this robot is quite easy to reproduce. What little robots have you build lately? Send us a tip and let us know!

[via Embedded Lab]


Filed under: robots hacks

An Etch-A-Sketch to Fetch the Time

ศุกร์, 03/28/2014 - 15:01

For someone who has never used stepper motors, real-time clocks, or built anything from scratch, [Dodgey99] has done a great job of bending them to his will while building his Etch-A-Sketch clock.

He used two 5V stepper motors with ULN2003 drivers. These motors are mounted on the back and rotate the knobs via pulleys. They are kind of slow; it takes about 2 1/2 minutes to draw the time, but the point of the hack is to watch the Etch-A-Sketch. [Dodgey99] is working to replace these steppers with Nema 17 motors which are much faster. [Dodgey99] used an EasyDriver for Arduino to drive them. He’s got an Arduino chip kit in this clock to save on the BOM, but you could use a regular Arduino. He left out the 5V regulator because the EasyDriver has one.

[Dodgey99] has published three sketches for the clock: one to set up the RTC so that the correct time is displayed once the Etch-A-Sketch is finished, some code to test the hardware and sample the look of the digits, and the main code to replace the test code.

The icing on this timekeeping cake is the acrylic base and mounting he’s fashioned. During his mounting trials, he learned a valuable lesson about drilling holes into an Etch-A-Sketch. You can’t shake an Etch-A-Sketch programmatically, so he rotates it with a Nema 17. Check it out after the jump.

If you’re paying attention, you’ll realize we just saw the exact opposite of this project a few hours ago: a CNC tool (laser cutter) controlled by turning Etch-A-Sketch knobs.


Filed under: Arduino Hacks, clock hacks

riotNAS: Mobile Storage for Street Photography

ศุกร์, 03/28/2014 - 12:01

You’re likely aware of the protests and demonstrations happening throughout Venezuela over the past few months, and as it has with similar public outcries in recent memory, technology can provide unique affordances to those out on the streets. [Alfredo] sent us this tip to let us know about riotNAS: a portable storage device for photos and videos taken by protesters (translated).

The premise is straightforward: social media is an ally for protesters on the ground in these situations, but phones and cameras are easily recognized and confiscated. riotNAS serves up portable backup storage via a router running OpenWRT and Samba. [Alfredo] then connected some USB memory for external storage and a battery that gives around 4 hours of operating time.

For now he’s put the equipment inside a soft, makeup-looking bag, which keeps it inconspicuous and doesn’t affect the signal.  Check out his website for future design plans—including stashing the device inside a hollowed out book—and some sample photos stored on the riotNAS system. If you’re curious what’s going on in Venezuela, hit up the Wikipedia page or visit some of the resources at the bottom of [Alfredo's] site.


Filed under: digital cameras hacks, Network Hacks

Laser Cutter Becomes An Etch A Sketch

ศุกร์, 03/28/2014 - 09:01

The mirror in a laser cutter moves along an X Y axis. An Etch A Sketch moves its stylus along an X Y axis. Honestly, this laser cutter with Etch A Sketch controls is so obvious, we’re shocked we haven’t seen it before.

The Etch A Sketch interface is extremely simple – just two rotary encoders attached to laser cut knobs set inside a small, laser cut frame. The lines from the encoders are connected to an Arduino Pro Mini that interfaces with the controller unit on the laser cutter, moving the steppers and turning on the laser only when the head is moving. There’s an additional safety that only turns on the laser when the lid is closed and the water pump is running.

The circuit is extremely simple, and with just a few connections, it’s possible to retrofit the Etch A Sketch controller to the laser cutter in just a few minutes.  Just the thing for a weekend hackerspace project.

 


Filed under: laser hacks

Developed on Hackaday: Need Card Art — Who Likes to Draw?

ศุกร์, 03/28/2014 - 04:54

Our offline password keeper project (aka Mooltipass) is quite lucky to have very active (and very competent) contributors. [Harlequin-tech] recently finished our OLED screen low level graphics library which (among others) supports RLE decompression, variable-width fonts and multiple bit depths for fonts & bitmaps. To make things easy, he also published a nice python script to automatically generate c header files from bitmap pictures and another one to export fonts.

[Miguel] finished the AES encryption/decryption schemes (using AES in CTR mode) and wrote an awesome readme which explains how everything works and how someone may check his code using several standardized tests. We highly encourage readers to make sure that we didn’t make any mistake, as it was one of you that suggested we migrate to CTR mode (thanks [mate]!).

On the hardware side, we launched into production the top & bottom PCBs for Olivier’s design. We’re also currently looking for someone that has many Arduino shields to make sure that they can be connected to the Mooltipass. A few days ago we successfully put the Arduino bootloader inside our microcontroller and made the official Arduino Ethernet shield work with it.

Finally, as you may have guessed from the picture above our dear smart card re-sellers can pretty much print anything on them (these are samples). If one of you is motivated to draw something, please contact me at mathieu[at]hackaday.com!

On a (way) more childish note, don’t hesitate to give a skull to the mooltipass on HaD projects so it may reclaim its rightful spot as “most skulled“.


Filed under: Hackaday Columns, hardware

Designing a WakeUp Light

ศุกร์, 03/28/2014 - 03:00

[Akhil] and his wife recently finished their WakeUp Light project. As the name suggests, this kind of morning alarm uses light to wake you up in the morning. The main constraints when starting this relationship-strengthening adventure were cost, ability to work with any table lamp, and having a simple but effective control interface, all while keeping all the design open. The created platform (put in the wooden box shown above) is built around a Stellaris Launchpad (ARM Cortex M4 based) and uses an AC dimmer circuit found in this instructable. For our readers interested in those, [Akhil] mentions two very interesting articles about their theory of operation here and here.

An Android application has been made to set up all the alarm parameters, which uses the phone’s Bluetooth to communicate with the (well-known) HC-05 Bluetooth transceiver connected to the Launchpad. For safety, the current design also includes an LM4876 based audio amplifier connected to the microcontroller’s PWM output. The next revision will integrate a Digital to Analog Converter and an SD-Card slot for better quality and music diversity. A presentation video is embedded after the break and you can find the official repository at GitHub.


Filed under: ARM, hardware, lifehacks

Fail of the Week: Secret Agent-Style Book Hideaway

ศุกร์, 03/28/2014 - 00:01

Ah, the movies are an inspiration for so many projects. How many times have you seen a spy movie where a cutout in the pages of a book are hiding something? This was the inspiration which led [Paul] and his crew to try using a laser cutter to remove a handgun-shaped cutout from the pages. The fail began before the project even got started. The sacrificial book they had chosen was too thick to cut directly so they tore it in thirds for the cutting process.

The hijinks are portrayed well in the clip after the break. The infectious giggling as this first trace of the laser cuts the outline makes the video worth watching. As they try to go deeper, the success falls off rapidly. This makes for a great Fail of the Week discussion: Why can’t you cut through multiple layers of a book with a laser cutter? Is this merely a focal length issue that would be solved with a higher-end cutter or is there something else at play here. Let us know what you think by leaving a comment below.

 

[Thanks Bob]

Fail of the Week is a Hackaday column which runs every Wednesday. Help keep the fun rolling by writing about your past failures and sending us a link to the story – or sending in links to fail write ups you find in your Internet travels.


Filed under: Fail of the Week, Hackaday Columns, laser hacks

Telepresence Robot Proves It’s A Small World After All

พฤ, 03/27/2014 - 21:01

[Chris] works as part of a small team of developers in Cambridge, Massachusetts in the US. [Timo], one of their core members, works remotely from Heidelberg, Germany. In order to make [Timo] feel closer to the rest of the group, they built him a telepresence robot.

It was a link to DoubleRobotics that got the creative juices flowing. [Chris] and his team wanted to bring [Timo] into the room, but they didn’t have a spare $2499 USD in their budget. Instead they mated a standard motorized pan/tilt camera base with an RFduino Bluetooth kit. An application running on [Timo's] phone sends gyroscope status through the internet to the iPad on the robot. The robot’s iPad then sends that data via Bluetooth to the RFduino. The RFduino commands pan and tilt movements corresponding with those sensed by the gyroscope.  A video chat application runs on top of all this, allowing [Timo] to look around the room and converse with his coworkers.

All the source code is available via GitHub. The design didn’t work perfectly at first. [Chris] mentions the RFduino’s Bluetooth API is rather flaky when it comes to pairing operations. In the end the team was able to complete the robot and present it to [Timo] as a Valentine’s Day gift. For [Chris'] sake we hope [Timo] doesn’t spend too much of his time doing what his homepage URL would suggest: “screamingatmyscreen.com”

[Thanks Parker]


Filed under: news

Hackaday 68k: So You Want A Kit?

พฤ, 03/27/2014 - 18:00

It’s yet another update to the Hackaday 68k, the wire-wrapped backplane computer that will eventually be serving up our retro site.

This is also a demo of Hackaday Projects, our new, fancy online documentation tool for all your adventures in making and tinkering. Did you know we’re having a contest on Hackaday Projects? Make something sci-fi, and you’re in the running for some really good prizes. There’s soldering stations, o-scopes, and a lot of other prizes being thrown at the winners. It’s awesome. First one to build a working Mr. Fusion wins.

In this update, I’m going to go over the beginnings of the video board, why Hammond enclosures are awesome and terrible at the same time, and some thoughts on turning this into a kit or product of some type. Click that, ‘Read more…’ link.

 

The Video Board

Like I’ve said before, I’m using the Yamaha V9938 video display processor as the graphics chip on this computer. It’s the easiest way I can get an 80×24 text mode – perfect for that *NIX goodness – and should be able to pull off some cool demoscene stuff. It’s pin compatible with the V9958, so I have that option, and it’s also fairly simple to interface to the rest of the computer:

That’s from the V9938 Technical Data Book. Big PDF warning there. On the right side of that graphic is the DRAM interface for the video memory and the pins for video output. There are a few different configurations ranging from 16k of VRAM to 128k of VRAM. Of course I’m going with the 128k option, using a quartet of TMS4464 DRAM chips I picked up from Jameco. Here’s the schematic of the VRAM interface:

I don’t want to wire wrap that. It’s a lot of fiddly, short bits of wire. It’s also extremely simple and won’t be seeing any changes in its design.  The solution to my laziness is, of course, to make a PCB.

Because the connections to the V9938 are just an 8-bit data bus and a few control signals, and the output is dead simple for composite output, this greatly minimizes the amount of wirewrapping I’ll need to do. Even if I tried wrapping a V9938, I’d run into a problem: the pin pitch isn’t 0.1″, rendering all my wirewrap adapters useless.

If you’re wondering about the physical size of the board, it’s just a wee bit larger than an Arduino. Yes, I know what you’re thinking, but a 128kB V99X8 will not fit on a standard Arduino shield. 16kB, maybe. In any event, when I get these boards back, I’ll have a go at driving it with an Arduino. Just because.

Mechanical Considerations

Yeah! Fancy Video!

I’ve never had any luck with Hammond enclosures. The die-cast aluminum guitar pedals? I’ve ruined dozens of them drilling holes for pots, switches, and jacks. The enclosure for the 68k is no different. It’s a beautiful case, no doubt about that, but I am cursed with a mystical ability to always mess up the drilling, painting, or some random thing when it comes to Hammond enclosures.

The original plan for this backplane + enclosure combo was to have a small extension board on the front (hence, “frontplane”) that broke out the power and reset lines so this computer would at least look the part of an early 80s homebrew computer. Also, having a power and reset switch on the outside of the case is a good idea anyway.

Because of the complete failure of my ‘frontplane’ plan with the stock front panel, I’m going for something much, much cooler: a custom CNC’d aluminum panel. Right now I have holes for a power switch, a reset button, and a 5mm LED for power indication.

The basic circuit for this frontplane is very simple: The lines on the backplane are broken out on a huge 2×32 pin header. There’s also a small three-pin header for the PS_ON and POWER_OK lines for the ATX power supply. Ground the PS_ON line with the switch, and the power… uh, turns on. The PS_ON line provides +5V when the power is on. Attach the LED to that.

The reset circuit is the same from the CPU board: a Maxim DS1812 supervisory and reset circuit in a single TO-92 package.

Creating the milled front panel and new, improved frontplane was an interesting exercise in mechanical design. First, I created the front panel as a 3D model, exported the top view as a DXF, and imported that into Eagle. Then, I took the board file for the backplane and overlaid the holes. Then it’s just a simple matter of removing the parts and traces from the backplane I don’t need – everything except the pin headers – and making a board.

Apparently the Dimension layer in Eagle has a keepout. This board is far too simple for me to care about doing it properly.

So there you go. Fun adventures in mixing mechanical design with circuit board creation. This, like just about everything else relating to the 68k project, is up on the github.

Oh yeah, a kit

For some reason I can’t comprehend, a lot of people have asked if I’m going to make the 68k into a product, or at the very least a kit. I don’t quite understand the demand; the fun of homebrew computers is designing and building them.

That doesn’t mean I won’t entertain the idea. In its current form, though, a 68k kit would be absurdly expensive, take hours and hours to assemble – the RAM card alone would be three or four hours – and would have an extremely high number of unsatisfied buyers. It only takes one misplaced wire to screw the entire thing up, you know.

So, an improved,  single-PCB kit is the only option. This is months and months in the future, but here’s what I’m thinking:

  • Uses the currently-in-production 68SEC000
  • Already assembled.
  • A MiniITX or MicroATX motherboard form factor.
  • Uses 30 or 72-pin SIMMs for the RAM.
  • Some sort of expansion port.
  • User-updatable ROM.

That last bullet is the sticking point. I’ve been turning this around in my head for a while, and I can’t come up with a good way of doing it. The problem is I need a small amount (~64kB) of EEPROM or Flash that can be accessed on a parallel bus. That means 15 address lines, 16 data lines, and control signals. I need a way of reprogramming this, in system, with few additional parts, cheaply.

The obvious solution is to throw a big FPGA in the system for address decoding, an SPI bus, and in-system reprogramming of the ROM. That may end up being the eventual solution to this problem, but I’m thinking there’s an even more clever and cheaper way of doing things.

I’ve toyed around with doing the whole ‘in system ROM reprogramming’ thing in a 6502-based retrocomputer, and it is possible by using a microcontroller and a bunch of shift registers to program the ROM. This takes up a lot of board space and is extremely kludgy.

Another solution would be something like this amazing retrocomputer that actually should be a product. It uses a 40-pin PIC microcontroller as the RAM, ROM, and ACIA. It is, without question, the most innovative project in the retrocomputing world for the past few years and presents an interesting solution to the problem of in-system ROM programming: just put the ROM on a big microcontroller.

Are any of these ideas the right solution? I don’t know, because I’m not designing this computer as a product right now. This problem has been bothering me for a while, and I’d love to hear some more ideas. In any event, there’s plenty of space on my ROM board to prototype some in-system reprogramming. Come up with a good idea and I might put it in.

That’s it for now. You can continue to follow the progress of the Hackaday 68k over on Hackaday Projects. Be sure to comment and give a skull to the project. Seriously, give the project a skull. I’m losing to [Mathieu]‘s Mooltipass project in the skull department. I need more skulls.

 

 

 


Filed under: Hackaday Columns

Hackaday 68k: So You Want A Kit?

พฤ, 03/27/2014 - 18:00

It’s yet another update to the Hackaday 68k, the wire-wrapped backplane computer that will eventually be serving up our retro site.

This is also a demo of Hackaday Projects, our new, fancy online documentation tool for all your adventures in making and tinkering. Did you know we’re having a contest on Hackaday Projects? Make something sci-fi, and you’re in the running for some really good prizes. There’s soldering stations, o-scopes, and a lot of money being thrown at the winners. It’s awesome. First one to build a working Mr. Fusion wins.

In this update, I’m going to go over the beginnings of the video board, why Hammond enclosures are awesome and terrible at the same time, and some thoughts on turning this into a kit or product of some type. Click that, ‘Read more…’ link.

 

The Video Board

Like I’ve said before, I’m using the Yamaha V9938 video display processor as the graphics chip on this computer. It’s the easiest way I can get an 80×24 text mode – perfect for that *NIX goodness – and should be able to pull off some cool demoscene stuff. It’s pin compatible with the V9958, so I have that option, and it’s also fairly simple to interface to the rest of the computer:

That’s from the V9938 Technical Data Book. Big PDF warning there. On the right side of that graphic is the DRAM interface for the video memory and the pins for video output. There are a few different configurations ranging from 16k of VRAM to 128k of VRAM. Of course I’m going with the 128k option, using a quartet of TMS4464 DRAM chips I picked up from Jameco. Here’s the schematic of the VRAM interface:

I don’t want to wire wrap that. It’s a lot of fiddly, short bits of wire. It’s also extremely simple and won’t be seeing any changes in its design.  The solution to my laziness is, of course, to make a PCB.

Because the connections to the V9938 are just an 8-bit data bus and a few control signals, and the output is dead simple for composite output, this greatly minimizes the amount of wirewrapping I’ll need to do. Even if I tried wrapping a V9938, I’d run into a problem: the pin pitch isn’t 0.1″, rendering all my wirewrap adapters useless.

If you’re wondering about the physical size of the board, it’s just a wee bit larger than an Arduino. Yes, I know what you’re thinking, but a 128kB V99X8 will not fit on a standard Arduino shield. 16kB, maybe. In any event, when I get these boards back, I’ll have a go at driving it with an Arduino. Just because.

Mechanical Considerations

Yeah! Fancy Video!

I’ve never had any luck with Hammond enclosures. The die-cast aluminum guitar pedals? I’ve ruined dozens of them drilling holes for pots, switches, and jacks. The enclosure for the 68k is no different. It’s a beautiful case, no doubt about that, but I am cursed with a mystical ability to always mess up the drilling, painting, or some random thing when it comes to Hammond enclosures.

The original plan for this backplane + enclosure combo was to have a small extension board on the front (hence, “frontplane”) that broke out the power and reset lines so this computer would at least look the part of an early 80s homebrew computer. Also, having a power and reset switch on the outside of the case is a good idea anyway.

Because of the complete failure of my ‘frontplane’ plan with the stock front panel, I’m going for something much, much cooler: a custom CNC’d aluminum panel. Right now I have holes for a power switch, a reset button, and a 5mm LED for power indication.

The basic circuit for this frontplane is very simple: The lines on the backplane are broken out on a huge 2×32 pin header. There’s also a small three-pin header for the PS_ON and POWER_OK lines for the ATX power supply. Ground the PS_ON line with the switch, and the power… uh, turns on. The PS_ON line provides +5V when the power is on. Attach the LED to that.

The reset circuit is the same from the CPU board: a Maxim DS1812 supervisory and reset circuit in a single TO-92 package.

Creating the milled front panel and new, improved frontplane was an interesting exercise in mechanical design. First, I created the front panel as a 3D model, exported the top view as a DXF, and imported that into Eagle. Then, I took the board file for the backplane and overlaid the holes. Then it’s just a simple matter of removing the parts and traces from the backplane I don’t need – everything except the pin headers – and making a board.

Apparently the Dimension layer in Eagle has a keepout. This board is far too simple for me to care about doing it properly.

So there you go. Fun adventures in mixing mechanical design with circuit board creation. This, like just about everything else relating to the 68k project, is up on the github.

Oh yeah, a kit

For some reason I can’t comprehend, a lot of people have asked if I’m going to make the 68k into a product, or at the very least a kit. I don’t quite understand the demand; the fun of homebrew computers is designing and building them.

That doesn’t mean I won’t entertain the idea. In its current form, though, a 68k kit would be absurdly expensive, take hours and hours to assemble – the RAM card alone would be three or four hours – and would have an extremely high number of unsatisfied buyers. It only takes one misplaced wire to screw the entire thing up, you know.

So, an improved,  single-PCB kit is the only option. This is months and months in the future, but here’s what I’m thinking:

  • Uses the currently-in-production 68SEC000
  • Already assembled.
  • A MiniITX or MicroATX motherboard form factor.
  • Uses 30 or 72-pin SIMMs for the RAM.
  • Some sort of expansion port.
  • User-updatable ROM.

That last bullet is the sticking point. I’ve been turning this around in my head for a while, and I can’t come up with a good way of doing it. The problem is I need a small amount (~64kB) of EEPROM or Flash that can be accessed on a parallel bus. That means 15 address lines, 16 data lines, and control signals. I need a way of reprogramming this, in system, with few additional parts, cheaply.

The obvious solution is to throw a big FPGA in the system for address decoding, an SPI bus, and in-system reprogramming of the ROM. That may end up being the eventual solution to this problem, but I’m thinking there’s an even more clever and cheaper way of doing things.

I’ve toyed around with doing the whole ‘in system ROM reprogramming’ thing in a 6502-based retrocomputer, and it is possible by using a microcontroller and a bunch of shift registers to program the ROM. This takes up a lot of board space and is extremely kludgy.

Another solution would be something like this amazing retrocomputer that actually should be a product. It uses a 40-pin PIC microcontroller as the RAM, ROM, and ACIA. It is, without question, the most innovative project in the retrocomputing world for the past few years and presents an interesting solution to the problem of in-system ROM programming: just put the ROM on a big microcontroller.

Are any of these ideas the right solution? I don’t know, because I’m not designing this computer as a product right now. This problem has been bothering me for a while, and I’d love to hear some more ideas. In any event, there’s plenty of space on my ROM board to prototype some in-system reprogramming. Come up with a good idea and I might put it in.

That’s it for now. You can continue to follow the progress of the Hackaday 68k over on Hackaday Projects. Be sure to comment and give a skull to the project. Seriously, give the project a skull. I’m losing to [Mathieu]‘s Mooltipass project in the skull department. I need more skulls.

 

 

 


Filed under: Hackaday Columns

3 DOF Open Source Robot Arm Is Just the Beginning

พฤ, 03/27/2014 - 15:01

[Dan Royer] of Marginally Clever had a dream. A dream to build an open-source 6 DOF robot that anyone can make! To do so, he’s been learning robotics for the past two years, and has just finished the first step — he’s designed and built an open source 3 DOF palletizing robot!

He’s based this little guy off of the commercial ABB 460 palletizing robot, which is a tried and true industrial robot. It features all laser cut parts, a few nuts and bolts, some stepper motors and an Arduino UNO for the brain. He’s released all of the design files on Thingiverse and the firmware on GitHub – yet another project we’d like to build if only we had a laser cutter!

And don’t worry, the Arduino UNO is only being used for this first prototype — he’s already started writing code for the RUMBA (Reprap Universal Mega Board with Allegro-driver) controller for revision 2.

Stick around to see it write its first greeting with a marker — Hello World!

It’s an exciting project and we can’t wait to see further development! Keep up the good work [Dan]!

Maybe we can teach it manually in the future too!

 


Filed under: Arduino Hacks, robots hacks

3 DOF Open Source Robot Arm Is Just the Beginning

พฤ, 03/27/2014 - 15:01

[Dan Royer] of Marginally Clever had a dream. A dream to build an open-source 6 DOF robot that anyone can make! To do so, he’s been learning robotics for the past two years, and has just finished the first step — he’s designed and built an open source 3 DOF palletizing robot!

He’s based this little guy off of the commercial ABB 460 palletizing robot, which is a tried and true industrial robot. It features all laser cut parts, a few nuts and bolts, some stepper motors and an Arduino UNO for the brain. He’s released all of the design files on Thingiverse and the firmware on GitHub – yet another project we’d like to build if only we had a laser cutter!

And don’t worry, the Arduino UNO is only being used for this first prototype — he’s already started writing code for the RUMBA (Reprap Universal Mega Board with Allegro-driver) controller for revision 2.

Stick around to see it write its first greeting with a marker — Hello World!

It’s an exciting project and we can’t wait to see further development! Keep up the good work [Dan]!

Maybe we can teach it manually in the future too!

 


Filed under: Arduino Hacks, robots hacks

Building a Network Controllable RGB LED Lamp from an Old Scanner

พฤ, 03/27/2014 - 12:01

Being able to use one of your old projects to make a new one better can be quite satisfying. [Steve] from Hackshed did just this: he integrated an Arduino based webserver into a new network controllable RGB lamp.

What makes this lamp unique is that the RGB LED bar comes from an old Epson scanner. Recycling leftover parts from old projects or derelict electronics is truly the hacker way. After determining the pinout and correct voltage to run the LEDs at, the fun began. With the LED bar working correctly, the next step was to integrate an Arduino based webserver. Using an SD card to host the website and an Ethernet Arduino shield, the LEDs become network controllable. Without missing a beat, [Steve] integrated a Javascript based color picker that supports multiple web browsers. This allows the interface to look quite professional. Be sure to watch the lamp in action after the break!

The overall result is an amazing color changing lamp that works perfectly. All that is left to do is create a case for it, or integrate it into an existing lamp. This is a great way to use an LED strip that would have otherwise gone to waste. If you can’t find a scanner with a color wand like this one, you can always start with an RGB strip.


Filed under: Network Hacks

Building a Network Controllable RGB LED Lamp from an Old Scanner

พฤ, 03/27/2014 - 12:01

Being able to use one of your old projects to make a new one better can be quite satisfying. [Steve] from Hackshed did just this: he integrated an Arduino based webserver into a new network controllable RGB lamp.

What makes this lamp unique is that the RGB LED bar comes from an old Epson scanner. Recycling leftover parts from old projects or derelict electronics is truly the hacker way. After determining the pinout and correct voltage to run the LEDs at, the fun began. With the LED bar working correctly, the next step was to integrate an Arduino based webserver. Using an SD card to host the website and an Ethernet Arduino shield, the LEDs become network controllable. Without missing a beat, [Steve] integrated a Javascript based color picker that supports multiple web browsers. This allows the interface to look quite professional. Be sure to watch the lamp in action after the break!

The overall result is an amazing color changing lamp that works perfectly. All that is left to do is create a case for it, or integrate it into an existing lamp. This is a great way to use an LED strip that would have otherwise gone to waste. If you can’t find a scanner with a color wand like this one, you can always start with an RGB strip.


Filed under: Network Hacks

Electric Scooter MK 1 — Tundra Upgrade!

พฤ, 03/27/2014 - 09:01

After discovering his all-terrain snow scooter was terrible on ice — [Dane] decided he needed to do some upgrades.

In case you don’t remember, we first shared [Dane's] project back in December, where he zipped around city streets covered in snow. The scooter used a big knobby tire and a front ski to slide around on. To make it suitable for ice, he had to redesign it a bit to handle slippery surfaces; he needed to give it skates.

He had originally hoped to find figure skates at a thrift store (where he originally found the classic scooter), but had no luck — so he made his own. Some 1/2″ x 1/4″ steel bar later, a bit of welding, and he had a rather rugged front skate to work with!

After he was content with his upgraded front-end, he started adding studs to the back tire. He’s using plain old 3/8″ self tapping screws, and a whole lot of epoxy to make sure they stay in.

So does it work? Oh yeah.

 

 


Filed under: transportation hacks

Piezos For Haptic Feedback

พฤ, 03/27/2014 - 06:00

The most common way to put some sort of haptic feedback in an interface hasn’t changed much since the plug-in rumble pack for the Nintendo 64 controller – just put a pager motor in there and set it spinning when the user needs to feel something. This method takes a relatively long time to spin up, and even the very cool Steam controller with voice coiled directional pads can’t ‘stick’, or stay high or low to notify the user of something.

[Tim]‘s day job is working with very fancy piezoelectric actuators, and when an opportunity came up to visit the Haptics symposium, he jumped at the chance to turn these actuators into some sort of interface. He ended up creating two devices: a two-piezo cellphone-sized device, and a mouse with a left click button that raises and lowers in response to the color of the mousepad.

The cellphone device contains two piezo actuators with a 10 gram weight epoxied on. A small microcontroller and piezo driver give this pseudo phone the smoothest vibrations functions you can imagine. The much more innovative color-sensing mouse has a single actuator glued to the left button, and a photosensor in the base. When the mouse rolls over a dark square on a piece of paper, the button raises. Rolling over a lighter area, the button lowers. It’s all very, very cool tech and something we’ll probably see from Apple, Microsoft, or Sony in a few years.

Videos of both devices below.

 


Filed under: hardware

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