Jeff's Arduino Blog

MRF24WB0MA Not Working... Yet

2012-01-31T15:26:00.001-08:00

I tried the test sketch from the i/o Blog, and... nothing! The Script got stuck in the initializing() function, and kept resetting every few seconds. I added a little debugging to narrow it down, looks like it just won't connect. To do:

The wiring: I need to check everything, I really thought it was wired up right. Also I wonder about grounding more of the module's pins, to be closer to the WiShield schematic (right).
The module might be having a hard time talking to my AirPort, so I'll try turning off security for testing. If that doesn't work, I'll try setting up a second network with one of the misc. wireless routers I've got in the digital dustbin.
Look around for other simple example sketches, there might be more info on this module and Arduino in the links I scraped together for the first post on the module.

MRF24WB0MA Breakout

2012-01-04T11:54:00.001-08:00

I soldered this up last night, using an EAGLE CAD board layout to guide me. The headers are set up and labeled and I'm ready to use the example from i/o blog-- more tonight!

WiFi Module for Arduino Projects

2012-01-03T16:29:00.000-08:00

Microchip offers a small (21 mm x 31 mm) WiFi module-- the MRF24WB0MA (rolls off the tongue, eh?), datasheet here (pdf)-- for under $24. Talking to it looks straightforward, and a few people have folded it into their projects with great results.

THANKS to the fine folks at Farnell (Newark if you're in the US, like me), I find myself with one of these amazing little modules, and I'm starting to explore using it in a project or two.

The module is wired up for easy use in the products listed below (and probably more), but the prices all seem high to me given that you're paying more for the supporting circuitry than for the WiFi module itself:

AsyncLabs used to sell a few products based on the MRF24WB0MA: the BlackWidow Arduino-compatible board ($75), compact YellowJacket ($55) Arduino-compatible, and the WiShield Arduino shield ($55). AsyncLabs stopped sales last March, but fortunately EAGLE-format schematics and board files are still online (eg. WiShield V1 and V2) and the library for Arduino too.
Diligent sells a PmodWiFi ($60) module with a 12-pin (2x6, .1" pitch) header.
Microchip sells a Wi-Fi PICtail/PICtail Plus breakout module ($60) with a 28-pin (2x14, .1" pitch) header,
MikroElektronika has two options using MRF24WB0MA's: WiFi PROTO ($54) and EasyWiFi ($59).
OpenPICUS sells the Flyport module (€49, ~$64) which includes a Microchip PIC 24F and has an IDE for programming as a standalone module.
Seeed Studio sells the WiFi Bee ($70) with 2.0mm XBee header breakouts and an ATmega328 on board.

I first saw details on using the module on its own on i/o Blog, where Manis chronicled his success using the module with minimal components, building a stripped down version of the AsyncLabs WiShield and building a sketch with the library. More on that in the next post...

IEEE Spectrum: The Making of Arduino

2011-11-07T13:30:00.000-08:00

An excellent article in IEEE Spectrum magazine gives a rundown of the origin of the Arduino board, outlining the motivations behind the open source design and the increasing impact it has on creative communities all over the world. It's a good read for answering the question, "What is Arduino?"

Flight Suit Excursions, Grinder Timer V4

2011-11-03T16:23:00.000-07:00

I've had a lot of fun with my Arduino-based projects lately! I got the flight suit working again for Decompression last month and had a blast dancing and hanging out in the crushing crowds. I wore it again last Saturday night for the work Halloween party and then again Monday night for 7 Walkers at the Great American Music Hall where Liz balanced out my high tech audio meter with her low tech VU meter-- analog and fully manual :)

Next up is V4 of the coffee grinder timer, a one-off to replace the V2 timer we're using now. It's an all-in-one circuit board designed to fit in a Hammond 1455-series case. There's an AC-DC converter on the board to supply 5V, and breakouts on the left (in white) for power and on the right (black) for the display, light sensor, rotary encoder, and lit button. I may finish it without the light sensor since it's so close to being done and looks so much better (especially on the inside!) than what we're running now.

Suit Success, Refurbishment...

2011-09-11T14:03:00.001-07:00

Three nights out on the playa, the light suit did not disappoint! So much fun to embody the bouncing red LED, for me and folks around me. It ran so much the second night-- music response mode and a high brightness can really draw current-- that I went through both batteries, ending the night unlit! The third night with all batteries charged and on-hand, there was no shortage of power and I ran it bright, but it was getting rough after so many miles, with a few segments not responding and a few dead 3-LED groups. All the time, the system worked beautifully, and I left it running when I finally took it off and stuffed it in a box Sunday morning, rippling and flickering, so bright before switching off.

Taking it out of the box Thursday in a puff of dust, a few segments did not respond but the system worked just as when I put away. I stripped out the main left arm board, all board-to-board cabling, the MOSFET boards, and then the light strips, pulling them off one at a time, removing the right arm accelerometer last. The suit and (surprisingly) sneakers made it through the wash and look great. I'm checking LED strips now, making a to-do list of fixes, remakes, and changes. I'll clean off all the boards and hook it together for a full pre-test, and then stuff it back in the suit.

Flight Suit Works!

2011-08-30T13:10:00.001-07:00

So much to do before we take off for BRC but the suit is fully functional!

I'll post photos and videos and all design files ~~after the long weekend~~ at some point, but here's a video showing the audio mode, which was the target all along:

Polishing work to deal with:

Test foot "A" and "B" strips Velcroed to shoes; hook and loop glue should be cured by tonight.
Finish remote control: straighten display, sand outside, glue top layers.
Tidy up buttonhole wiring and shift bands to correct alignment along Velcro loop bands.
Finalize light strip lengths: clip any extra length and seal ends.
Come up with a better remote control attachment... clip? hook? Velcro?
Make a cover for the ZX-Sound audio input board.

(F)Light Suit Progress: Almost There!

2011-08-24T20:43:00.000-07:00

So much progress in the last two weeks, the big milestones being...

I got the MOSFET boards and built three-- they worked right away! As expected I needed resistors between the 595 outputs and the MOSFETs; didn't notice that until I hooked up the third one and things weren't behaving. I'm not crazy about the screw terminals but they'll be OK.
Testing the MOSFET outputs with all 22 segments-- 53' of light, so bright! The first tests were just "All Fade" mode.
Expanding the program to sense arm angles. The routine automatically sets arm levels, either up/down or matching angle, and how many levels there are (since arms up can create a new level).
Adding a proper "Rolling" mode to sweep a band or bands over the whole suit, top to bottom, with variables delay (ms), brightness, direction, and number of bands (density). Seeing all the bands rolling through was a relief.
Sewing is awesome. I've sewn 10 out of 19 "loop" side Velcro bands into the suit: both legs and the hips and waist.
ZX-Sound works! Filtering and sampling will be the last things I dial in, but I have working bouncy light code, smoothed and at whatever Hz I want, dynamically computing the high and low so it will bounce if it's quiet or loud.

Still big items:

Integrate audio sketch into main line, finish filtering code, and use filtering code for gravity sketch,
Finish sewing hook-side Velcro strips onto the suit,
Cut the loop-side Velcro for the light strips and stick it on with silicone,
Measure and cut and route in-suit leads: 4 solder points each, 6 pieces of shrink,
Sew in conduit for left-to-right board, battery, audio, and accelerometer leads.
Address shoes, hat(s), headband mounting and routing...

That's all I can think of for now, back to sewing...

Nanode: Arduino-compatible with Ethernet

2011-08-11T12:13:00.000-07:00

The Nanode project from (the?) London Hackspace has been on my radar but didn't make the spreadsheet since I was waiting for it to become available. Well, it's out ($40 kit), and it seems to be a hit!

Unlike the Arduino Ethernet and shield and other boards with built-in ethernet, the Nanode does not use the Wiznet W5100, instead using the Microchip ENC28J60 found in JeeLabs EtherCard, and you can even program it over ethernet!

Not all rotary encoders are created equal...

2011-08-11T11:19:00.000-07:00

I had a hell of a time getting the (F)Light Suit remote control to work with the Modern Device LCD117 backpack and inexpensive BI EN11-HSM1AF15 rotary encoders. It turned out that I was having two issues:

The LCD117 was getting its updating commands too quickly, so chose to reset instead of display, and
the rotary encoders make contact so quickly when stepping up or down, my debounced code for bigger rotary encoders with more even click timing wasn't working.

Preventing the LCD117 from updating too quickly solved the first problem, and redoing the rotary encoder code from scratch solved the second problem. I'll post code later when the project is complete, but I based it on Max Wolf's very simple first example from the Arduino Playground rotary encoder page. The interrupt-based examples are too cryptic and (I think) unnecessary in a sketch that loops at a few KHz, which all of my sketches run at.

(F)Light Suit Major Components

2011-08-10T12:03:00.000-07:00

The main components of the (F)Light suit:
(Updated 8/15/11)

Component(s)	Source	Status
LED strips	DealExtreme	22 strips with connectors, need sealing and velcro backing.
8-channel MOSFET Output Boards	DorkbotPDX board order	Three built and tested, work perfectly
Arm accelerometers	Modern Device	Left one on main board, right attached with 3-wire lead across shoulders
Black flight suit	Amazon	Needs velcro for LED strips
Arduino-compatible main board: Minimalduino 105	DorkbotPDX board order
Arduino interface board: Adafruit protoshield	Adafruit Industries	Done, ready for mounting and cable threading. Ports for MOSFET output boards, right accelerometer, remote control, audio sensor
Remote control	homemade, various parts	Needs laser-cut acrylic surround, rot 2 flaky
Batteries	eBay	12V, 4800mAh Li-ion battery packs with barrel connectors, powering third MOSFET board.
Audio input: ZX-Sound board	RobotShop.com	Test, add light, change connector, paint, velcro back
Missing anything?

Ethernet Arduinos (and Compatibles)

2011-07-27T14:34:00.000-07:00

Also on the spreadsheet, three boards with built-in ethernet:

There's finally an official Arduino Ethernet ($60), complete with RJ45 port. It has an FTDI cable header for programming (no USB), a microSD card slot for storage, and there's an optional PoE daughter card.
SparkFun also released an Arduino-compatible board with ethernet, the Ethernet Pro ($55), but without the SD card slot. It's less cluttered than the official board, hopefully the price will come down as more people build projects around them.
Additionally, the Freetronics EtherTen ($70) includes a microSD slot and (mini) USB interface.

All of these are compatible with an Arduino (or Arduino-compatible) board with the ethernet shield ($40) on top, but I wonder: will shields fit on any of these without hitting the magjack? Or do they use taller female pin sockets? They're also equivalent to an Arduino hooked up to a Wiznet W5100, eg. with a WIZ811MJ module ($20!). Too bad Adafruit doesn't sell the ethernet module breakout shield anymore, but at least the design files are still available.

Call me cheap, but these all seem overpriced, being based around a $4 microcontroller! With a basic Arduino board at $20 and WIZ811MJ module at $20, why isn't the SparkFun Ethernet Pro $40 or $45?

More 'duinos on the Spreadsheet

2011-07-26T15:07:00.001-07:00

I've continued to add Arduino-compatible boards to the spreadsheet, bringing the count to 119 boards. You can get there easily by remembering "allarduinos" and going to http://tinyurl.com/allarduinos or http://bit.ly/allarduinos.

Some recent additions to the spreadsheet:

Three (!) clock boards from Wise Time With Arduino:
- Wise Clock 3 with a 32x16 Red-Green LED display (from Sure Electronics) has many different modes, including Pac Man, game of life, Pong, and... make your own!
- ClockTHREE Junior (aka C3Jr), a collaboration with WyoLum, which is similar to the QlockTWO readable clock.
- DWex, "Duino Watch for experimenters"-- chock full of SMD LED goodness; this actually came out last year but I missed it.
From SparkFun comes the PTH (plated through-hole) Kit, very similar to Diavolino and my Minimalduino, but surprisingly priced at $30. It doesn't seem up to SparkFun's high standards though, since there is no power switch and the electrolytic capacitors are too tall, so shields won't fit.

(F)Light Suit Progress: PWM!

2011-07-25T21:13:00.001-07:00

I had a frustrating time trying to get a PCA9685 working-- it wouldn't even reply with its register byte values. I've interfaced with other I²C chips and didn't expect problems, but trouble was all I got.

Poking around the Arduino Forum trying to find any examples with a PCA9685, I found the thread on Elco Jacobs' new ShiftPWM library to drive the outputs of the ubiquitous 74HC595 shift register with 8-bit PWM precision. His demo video is on the right. The example sketch was so straightforward, I had two chips driving-- and dimming-- 16 red LED's in minutes.

Once I saw those red LED's cycling, I considered that part of the project done-- thank you, Elco!-- and started laying out a driver board with a 74HC595, eight outputs hooked up to MOSFETs and test LED's, and screw terminals so they can be daisy chained. With the DorkbotPDX order deadline this morning, I had to stay up late laying it out and getting a final Eagle brd file ready, and hopefully it will work; I wasn't that excited about asking for six copies of a 3.9"x2.1" V001 design and having no time for a second run if they don't work, but... hey, they'll work!

Here's the Eagle schematic: pdf, sch. And the board: pdf, brd.

LED (F)Light Suit: Ramping Up

2011-07-17T12:27:00.000-07:00

I've been mesmerized by bouncing red LED's since the early '80s. LED's were mostly red, needle-style VU meters were on the outs, we hadn't yet graduated to green-yellow-red meters, and I grew a special place in my heart for those bouncing red lights. We also had KITT and the Cylons: bouncing red lights were and still are awesome ("rad" had not been invented yet).

I put together a black flight suit with red EL-wire segments for Burning Man in 2008 but did not have time to build the sequencer and control system I envisioned, so it was an on/off affair, or it pulsated to the music before the small batteries died.

Working on a suit for this year's burn, I've decided to return to the original concept-- red LED's-- and am working on the major areas now:

Suit electronics: Arduino core, I2C port expander w/PWM output using PCA9685 16-channel, 12-bit PWM I2C-bus LED controller driving power MOSFETs, one per segment. There are 17 segments in my design, so I'll use the port expander and then another spare pin to trigger the 17th channel.
Audio metering: I have a MaceTech Shifty VU shield working but I wonder about adjusting levels on the fly, and how to best get a mic input to it or something similar. There will be other modes for sequencing the lights, but bouncing VU meter is the primary mode I'm looking for.
Segment planning: location and length of each segment, power lead routing, attachment to suit. This is going well, with the first seven (of 22) segments cut and tested last night from my first 5M strip from DealExtreme; the suit will need 53' of light strip so I've ordered more.
Power: rechargable 12V power packs are easy to get; not sure how to recharge them on the Playa.
Remote control: would like to have a small, wireless remote to control modes and mode parameters.
The program: I have a list of modes I'd like to switch between, some of which have parameters I'll want to adjust on the fly. Ideally I'll be able to edit the program during the day if I come up with new ideas while I'm in BRC.

What is "Minimalduino"?

2011-07-16T15:00:00.000-07:00

I started working on the "minimalduino" design as...

a minimal hardware design for an Arduino-compatible board. At heart, it is very similar to the Dorkboard, but
designed to match the form factor of the "official" Arduino boards so users can benefit from the many, many shield boards designed to fit on top. While (awesome) boards like EMSL's Diavolino are also low-cost and shield-friendly, I wanted to explore
optional hardware configurations, with different power connector options (pin headers, JST connector, barrel jack, screw terminals, or mini USB jack), 5V and 3.3V power regulation and optional voltage switching and regulator bypassing, and options for crystal and caps or a resonator. I also wanted to have
better shield-friendliness by placing LEDs (power and D13) and the reset switch (side switch or top switch) at the edges of the board, and lastly, I wanted the board to be
single-sided, home-etchable with wide traces and minimal jumper wires. There is still work to be done to reduce jumpers, but it improves on the the S3V3 "Severino" board which doesn't match up size-wise (it's bigger), the standoff mounts don't match, and it uses a DB9 serial connector instead of the now widespread FTDI USB-serial breakout cable.

3-Digit 7-Segment Display With an SAA1064

2011-06-16T13:16:00.000-07:00

Working on the grinder timer project, I built out a basic circuit (EAGLE .sch) with an NXP SAA1064 and resurrected a test sketch (Arduino .pde) for it. The SAA1064 works beautifully for driving common anode 4-digit 7-segment displays with constant current per segment, from 3 to 21 mA in 3mA increments; in this case I'm only driving three digits since that's what the design calls for.

There are two buttons in the test sketch (on D10 and D11), the first to change count modes (seconds, tenths, hundredths, hex, and "chase") and the second to cycle through the seven current settings.

This schematic is identical to one I did a board layout for with an SO24 package chip, but for some reason those boards didn't work; maybe something in manufacture or assembly bridged pins somewhere. I'll redo the layout and see what happens, with vias further from pads.

Minimalduino 105: Nice!

2011-06-15T12:34:00.000-07:00

I built out one of the "V.105" boards I got a few weeks ago from the DorkbotPDX PCB order, and it works beautifully, almost identical to the version 107 I posted files of, with "5V/3.3V" voltage and "FTDI/IN" power selector switches. I mounted a mini USB socket and a 7805 regulator, in addition to the barrel jack for power in.

I've gone to whole number versioning btw, no need for "always under 1" versioning or major/minor versions, and if I need to go higher than 999 (huh?!), I can just use four digits.

Top and bottom labeling came out great, including the Open Hardware logo, though the letters mush together a little. Also, the "FTDI" header label didn't print at all, maybe there's a problem having two "FTDI" text labels.

One issue is that the drills for the main female headers are smaller than those on versions 89 and 97 boards, even though they use the same parts in EAGLE! I'll check the parts and maybe swap them out. That's a bummer-- I had to drill them all out to mount the headers, which ripped some of the pads off the fiberglass, but thankfully they stayed connected to the traces.

Minor edits for the next version:

Move the power input components to give electrolytic capacitors more room to accomodate shorter/fatter ones or taller ones mounted horizontally. As it is, the 100uF cap at the input is jammed between the .1uF cap and the barrel jack. [done]
Rotate LED's so they can be mounted horizontally for better side viewing when using a shield. [done]
Add heat sink polygon and vias under the 7805 tab.
Fix the Sparkfun mini USB through-hole part: its outline is on the bPlace layer, not tPlace where it belongs. Or just use a different part. [done]
Check female header drill diameters.
Add 2-pin header at the reset button to make it easier to add a remote panel-mounted reset button. [done]
Round the corners; looks nice on the Freetronics boards. Also check Uno outline and drills to make sure things are lined up right. [done]

I'm pretty happy with this for now though-- I have plenty of cheap, homemade, 5/3.3V-switchable Arduino-compatible boards to work with!

MinimalDuino 107 Pattern

2011-05-16T13:52:00.000-07:00

After submitting the 105c version to the DorkbotPDX PCB order, I mentioned I'd make one at home, but the traces looked so thin on paper and I didn't like the routing of gnd to the crystal area, so I made a few changes to optimize it for toner transfer and home etching.

Here's a shared folder with the updated, v107 EAGLE files and a 600dpi jpeg for toner transfer. See the low res at right, or click for higher res; get the full res jpeg here.

Minimalduino v.105: Curvy Trace Fun

2011-05-09T08:59:00.000-07:00

I've been trying out some Hope RFM12B radio modules-- very cool and inexpensive!-- which run off 3.3V. I've been using MinimalDuinos since they're 5V/3.3V switchable, and I got three version .97 boards made last year, with curvy traces, and they're coming in handy.

I have a few boards I'll need to get made over the next few months, so to warm back up with EAGLE, I polished up a straight (normal) trace version .105 board and set to curving it up. It took about an hour and a half, going around trace by trace in move mode, lots of command-clicking and dragging in the middle of trace segments to adjust their arcs. I submitted it to the DorkbotPDX PCB order before the deadline hit, and I can't wait to see what I get :) Design files and snapshots can be found here.

A key goal of the design is to have a good single-sided pattern for home etching, so I'll also make one by hand after fattening up as many traces as possible.

V.105 with straight traces:

Compare to V.105C, with curvy traces:

Spreadsheet: "Date Added" Column, More Boards

2011-02-25T17:52:00.000-08:00

So many people have asked for a column on the Arduino-compatible board spreadsheet showing the date when each board was added, so I put that on the spreadsheet this week. I had to sift through the revisions, but it wasn't too much of a pain.

Also new to the spreadsheet:

Six boards by the Indian company Bhasha, all through-hole except for the FTDI USB chips, mostly simple designs but it's clear from the traces that the boards were reworked slightly. Interesting to see the "Severino" Single Sided Serial V3 design offered for sale, something I haven't seen elsewhere.
Zigduino by Logos Electromechanical is offering their first run of IEEE 802.15.4 radio-equipped boards for $70. I've been looking forward to these boards coming out, but the price seems high given that you could buy an Arduino FIO for $25 and an XBee module for $19, so $44 total, or a Freakduino Chibi for $33. I hope the high price is only for this first run and that it is lower when Logos goes into full scale production, but I also wonder if it's as easy to use as the widely available XBee modules for which there are many example sketches available. It does have XBee "Pro" capabilities though, and I'm not familiar enough with 802.15.4 to really compare it to other offerings. I look forward to more complete documentation on its specs along with full design files since it's unclear what its equipment and capabilities are.

Open Source Hardware Definition 1.0

2011-02-25T10:55:00.000-08:00

The Open Source Hardware ("OSHW") definition version 1.0 was released a few weeks ago, and a bunch of organizations and people (like me!) have signed on in support of the definition and of OSHW in general.

One of my favorite parts, emphasis mine:

4. Derived Works
The license shall allow modifications and derived works, and shall allow them to be distributed under the same terms as the license of the original work. The license shall allow for the manufacture, sale, distribution, and use of products created from the design files, the design files themselves, and derivatives thereof.

If I'm reading that right, by allowing and not obliging derivative works to adhere to the definition, industry is encouraged to incorporate as much or as little OSHW thinking as they like into their products. I think this is key for encouraging manufacturers at large to think in terms of making their products hackable, but more importantly, servicable. Of course companies will need to lay out all kinds of disclaimers for when you break their products when you were trying to fix them, but that's already standard practice. This is getting interestinger all the time...

Spreadsheet Edits

2011-02-14T10:48:00.001-08:00

I've made some changes to my Arduino-compatible boards spreadsheet lately: I added a few boards, removed boards which are no longer available, and made some general changes.

Added:

	Stripduino by TinkerAct! has a small SMD area for its Arduino-compatible core, with IO pins in a line next to a stripboard area for on-board prototyping. There was an initial issue with the name of the board, but it seems straightened out now, and the design is lovely-- nothing extraneous. It reminds me of one of my favorite boards, Prototino by Spikenzie Labs.
	"Drum Kit - Kit AI" by SpikenzieLabs, a "maybe not" Arduino-compatible board for creating a MIDI 6-pad drum kit using piezo sensors stuck to just about anything.
	rEDI Education Board by Rogue Robotics is a prototyping board with buttons, LED's, a piezo speaker and volume knob, real time clock, high-powered 5V voltage regulator, servo headers, and a breadboard area. Also "maybe not" Arduino-compatible since it runs an ATmega644P, so it needs a custom bootloader.

Removed:

A bunch of boards by Fundamental Logic which apparently stopped accepting orders in May of 2010. That makes me sad since they offered some interesting boards, but thankfully the designs are still online for reference. My favorites: iDuino, StickDuino, MPGuino.
Modified Pico was a very compact, breadboard-friendly Duemilanove-compatible board. Thankfully details (including design files) are still available.
Rampage Robot Base V4 was an Arduino-powered robot platform with headers for a shield. Looks like its creator has moved on to more complex microcontrollers.
Zuccherino by Evil Mad Scientist Laboratories was to be "a low-cost, scalable, and extremely versatile open-source motion control platform," but the project has not had an update in a while. I look forward to more from this project.
"Flexi" was an inexpensive breadboard-friendly clone, not sure what happened but the domain now hosts a useless/spammy link page.

Changes:

I just added a "By" column for designer, author or manufacturer. I'd like it to be simply "Author," but some companies [cough] mostly sell other peoples' designs, so I'm not sure whom to credit.
I'd like to add more information about when boards were edited or checked, but wading through the revision history in Google Docs is a pain. A few people have suggested this and I like the idea, but I can't figure out how to track down the details.
I updated a bunch of boards' links, prices, and chip; a few use ATmega328s but used to be ATmega168s.

As always, please email me with any suggestions or corrections!

Minimal*duino V.96

2011-02-09T10:51:00.000-08:00

I've done a little work on my "Minimalduino" Arduino-compatible board design lately:

Moved the fourth standoff mount hole to line up with the Uno's new fourth standoff hole (which they didn't make aligned to the one across the way!).
Fattened up the traces to make it more home-etcher-friendly: .016" and .024" traces, .018" min. separation.
Spread out the components, reduced the jumper count, and removed the I2C header.
Added pads for a mini USB jack, for power only. (I'm not sure about the grounded heat sink of a 7805 shorting to the 5V trace so I put in a solder bridge, but it's fine for making at home using real wires for the top layer jumpers.) So many options for powering this sucker!

Files can be found here.

Thinking about running this at 3.3V, I don't think it would work right for programming or for running with the FTDI cable attached.

Update: I had some v.97 boards made (DorkbotPDX order ftw!), same as .96 but with curvy traces and a few parts moved a little, here's one assembled:

Arduino: What Direction?

2011-01-05T17:55:00.000-08:00

In spite of the year-end hype surrounding the Arduino Uno, and while I like seeing Arduino hit its 1.0 release, other Arduino-compatible boards get me more excited. If Arduino is a low hurdle access architecture for the ATmega**8 line of microcontrollers, I'd prefer the extra circuitry to be optional:

Power regulation: why embed regulation in each board when it's not always needed? And what about regulation or step-up converters for battery-powered projects?
Board voltage: There are good reasons to use 3.3V or 5V depending on applications, why are so few boards switchable?
Programming interface: While USB (and its decoder chips) is ubiquitous, so (still) are serial and ethernet, and (increasingly) XBee. Why not make the programming/serial interface optional or external?
Real estate: There is only so much room in the standard Arduino form factor. Why not use that space for useful circuitry that would be tricky to locate externally?

$30 is a fair price for a board with USB, power regulation, and automatic power switching, but half of that cost is not for the Arduino-capability! This is neatly demonstrated by the $13 Diavolino by Evil Mad Scientist Labs, which has no power regulation (but pads if you want to install it) and a header for the now standard 6-pin FTDI USB-serial breakout interface. Arduino-compatible boards' regulation, voltage, programming interfaces, and extra features are listed on my comprehensive spreadsheet.

Here are a few boards comparably-priced to the Uno that may be more useful for real applications since they have the Arduino core but different circuits for power, communication, or extra capabilities:

Wiseduino ($34 kit) has a DS1307 real time clock with backup battery, a 256Kbit EEPROM chip, header pins for the Adafruit XBee adapter, and 6-pin FTDI cable interface.
Freakduino Chibi ($33 kit) has built-in 802.15.4 (XBee) radio and optional ($3!) battery voltage regulation so you can input from .7V to 6V.
Arduino FIO ($25) has a MAX1555 LiPo charger, power regulation, and an XBee socket.

What do you want in an Arduino-compatible board? Please leave a comment!

Distracted...

2010-10-04T15:23:00.000-07:00

The laser has distracted me from Arduino-based pursuits for the last few weeks in spite of the Uno and Mega 2560 release (and subsequent kerfuffle) and the open source hardware summit and Maker Faire in NYC. Making a better ventilation and filtration system takes priority since I'll be able to make all sorts of things when I can run the laser whenever I want:

Cases and case front panels
Button caps and custom lit buttons
PCB etching (removing masking paint)
PCB post-etch scoring and labeling
PCB solder mask cutting
Motor mounting and simple gearing (like this?!).

Update 1/3/2011: I think the laser tube died on Dec. 29...:( Was engraving fine on one pass, then was just marking-- not cutting-- the next. Will try to repair, or else... replace? Rabbit or Epilog? [sigh]

EPILOG

2010-09-11T20:46:00.000-07:00

I replied to a Craigslist post for an old Epilog laser system w/PC, Corel, rotary attachment... complete pipeline.

It's sitting in my office now and it works....:D

More later... much to do...

Arduino Coffee Control Success!

2010-09-09T13:28:00.000-07:00

This morning, Liz woke up, tapped the bookmarked link on her iPhone, and then tapped "Click Mr. Coffee ON Button." A few minutes later, she went downstairs and was greeted with a fresh, hot pot of coffee :)

The circuit for Mr. Coffee ended up being different from what I'd planned when I got everything assembled for a final test: switching on power to the unit did not start the brewing; it needed to have the "ON" button pressed! So instead of switching power on with a relay, I soldered wires to the "ON" button's sides and ran them to the same relay. I edited the sketch in ten minutes to close the relay for a half second, uploaded it, and it worked perfectly.

Coffee Control

2010-09-07T00:21:00.000-07:00

It looks like we'll have remote control of the grinder timer by the end of the week, along with power for Mr. Coffee and the Gaggia Classic!

The first step (mentioned in my previous post) was to get my old (V1.0) Adafruit Ethernet Shield up and running with an XPort Direct+ and the color picker sketch on the examples page. Then I stripped down the sketch, reconfiguring it for general pin control: toggle outputs, set PWM output values, pulse, and read analog values. After that, I simplified it for the coffee control project which only needs three digital output pins.

One obstacle was getting my LAN to the kitchen counter, and an old AirPort Extreme from my scrap bin (found on the street!) did the trick: it now wirelessly bridges our home network via WDS and connects to the ethernet shield with a cable, its USB port powering my minimal Arduino-compatible board underneath with enough 5V power to spare for Mr. Coffee's relay; I'll add a 12V source for a bigger, higher power relay to switch the Gaggia Classic.

The Arduino side of the system works great, serving a web form (at right) to turn the two power relays on or off and to trigger the grinder timer. The last part is always the hardest, though: wiring and casing it all up. Safe wiring will take some time to nail down, with Mr. Coffee needing ~1025W and the Gaggia Classic rated at 1370W (!). As for the case itself, lucky for me some folks from Ponoko are scheduled to make a presentation tomorrow (er, later today ;) at the Make:SF Meetup-- just the info I need, right when I need it!

Workshop!

2010-08-17T13:13:00.000-07:00

After over a month of planning, boxing, and finally moving into a new home, I'm ready to get back to projects working in a dedicated workshop/office space!

Arduino-based projects, all within reach:

Mutetater: get it working for the Sharp TV I have, at least. This is more a challenge of IR encoding/decoding than anything else, so I'll reel back my code and try to re-approach the examples I've looked through before.
Resurrect Growduino for an herb garden on the upper desk, easy since there are power outlets available so I can sidestep solar power issues for now and get stuff growing.
Net-enabled coffee grinder timer so it can be controlled through a simple web interface, via an iPhone on the local network. I think it would mostly involve working with the ethernet shield, then maybe "shield-ifying" the grinder timer or building ethernet capability into the single-PCB circuit. Then I can start building out a control system for the Gaggia Classic.
Remote-controlled curtain system for the TV. Mostly involving IR decoding, simple (MOSFET) motor control, some limit switches, mounting hardware, and sewing.
PPAC: um, why aren't the relays firing?! Buttons work, so I need to disassemble it and check the output pins, then position the "pea" for exciting wake-up sequences.
Intervalometer ("intervalomejar"?): get a simple one working for timelapse using the FSM (Finite State Machine, not Flying Spaghetti Monster) library.

I'll add more later, just want to get a list going so I can start building some test sketches. Other tech to sketch for more complex projects:

PID for temperature and motor control
Temperature sensing for PID control: thermocouples

More Boards...

2010-07-10T17:02:00.000-07:00

Seems like I'm always finding more Arduino-compatible boards to add to the spreadsheet-- added four today, bringing the current count to 89. I remove some occasionally when I check and find the links are no good, but hopefully all of the listed boards really are available, or will be very soon.

Added today are Duemilanove and Mega clones from DF Robot, a Chinese company, as well as their Romeo robotics board (pictured, $36) which is essentially a Duemilanove with the SMD ATmega328's 2 extra analog pins exposed (Seeeduino style), male header pins, on-board buttons, I2C headers, and an L298 motor driver with screw terminals.

Also added is the Displayduino (pictured, $70, which I noticed at Sparkfun), the core of the MondoMatrix modular system for controlling large numbers of LEDs or servos or whatever. Displayduino acts like a Sanguino with USB, screw terminals, and an RS485 port driver for communication in addition to the ATmega644's two UARTs.

EMSL "Diavolino"!

2010-06-23T16:30:00.000-07:00

Windell from Evil Mad Scientist Laboratories ("EMSL") announced a new Arduino-compatible board today: Diavolino!

Designed to be programmed with an FTDI USB cable (6-pin), the awesome-looking $13 kit comes with just enough to get started, including an ATmega328 pre-loaded with the Arduino bootloader. Pin headers cost an extra $1.50, and you can power it with an optional $1 3xAA battery box with switch, which should supply 4.5V (using alkalines).

Very cool kit from some very cool people, and (according to my Arduino-compatible board spreadsheet,) currently the lowest-priced way to get access to the big wide world of Arduino shields.

Update 6/24: Added the EMSL Peggy 2LE and Bulbdial Clock to the spreadsheet, though they're "maybe not" really Arduino-compatible :)

DorkbotPDX PCB Order: Boards and Boards and...

2010-06-11T11:29:00.000-07:00

After missing the May 17 deadline, I was able to get two boards in for the May 31 DorkbotPDX PCB order. That order has taken longer than previous ones though, since the fab house quoted a much higher price than for previous orders. Fortunately, Laen was able to find a different manufacturer for the panel and stick with the $5/square inch (for three boards *shipped*) pricing structure-- woohoo!!

I submitted a 3-digit 7-segment display board (using an SAA1064) and an Arduino-compatible board with curvy traces and optional everything (including 3.3V operation).

The next deadline is this Monday, June 14 at 8AM, so tweak your designs this weekend and get your .brd or gerber files in!!

Rounded EAGLE Routing?

2010-05-14T09:43:00.001-07:00

Trying to spread traces around, I wondered how the rounded wire bend routing options worked in CadSoft EAGLE. There's a free-form, spline sort of wire bend option, and I went around to all the traces on the latest minimalduino version (which needs a better name btw), widening and pushing and pulling traces to try to fill empty areas. Sort of looks hand-drawn, kind of hippyish. I was hoping to find a way to eliminate one of the jumper wires, but no luck. I introduced an air-wire, actually, but can fix that with a little nudging.

Not sure whether to get a few of the rounded or "normal" versions when the DorkbotPDX PCB order is due. I got the idea trying to arrange the traces in the lower left and upper middle areas, after working in some patterning in the diagonals. Your opinions are most welcome!

Update 5/21/10: The mail to Laen at DorkbotPDX never sent?! Went to mail him asking him if they worked out, and the mail was in "Drafts". Stayed up late Sunday night tweaking them and... crap! Guess I'll have to wait for the next order; had a 3-digit 7-segment display board too, based on an SAA1064..:(

More *duinos

2010-04-29T17:10:00.000-07:00

Two new Arduino-compatible boards are out and are now listed in my big spreadsheet of boards.

The ArduPilot Mega by SparkFun ($60) is an extension of the original ArduPilot, but as its name implies, now sports an ATmega1280 as its main processor. Designed to be the brains behind a UAV or radio-controlled flying vehicle, it's all ready to hook up to a GPS receiver, servos, RC I/O, accelerometers and gyros, etc. It's amazing how much is packed in there-- it even has a secondary ATmega328 and multiplexer.

From Spikenzie Labs, the folks who make the Voice Shield and Altoids tin-sized Prototino comes a "SIP" (Single In-line Package) Arduino-compatible board "Sippino" ($16 kit). It can be mounted vertically or horizontally in a breadboard and has a 6-pin FTDI breakout header for programming, though no power regulation or reset.

Canon IR Remote Control

2010-04-15T02:37:00.000-07:00

After striking out at the Electronics Flea Market Saturday, I stopped at Fry's for a fresh pair of clippers and soldering tips, and picked up a small case too-- a Serpac M4. I used some free protoboard Laen sent me (THANKS!) to build a simple Arduino-compatible circuit to fit inside it, with a single button and IR LED, powered by three LR44 (AG13, 357, etc.) button cell batteries; basically a mutetater circuit with one LED instead of four.

Following Martin Koch's code example, I got the circuit to trigger my 350D's shutter, making it functionally equivalent to a Canon RC-5 remote control. Using an ATmega168 is overkill though: most pins go unused, and it nearly drained the three LR44 batteries when left on all night.

I figured putting it to sleep would solve the power consumption problem, so I modified the ArduinoSleepCode example from the Arduino Playground to make the D2 button both wake it up from sleep and trigger the shutter. It doesn't need to be awake for any time at all really before going into "SLEEP_MODE_PWR_DOWN": the wake up function triggers a shutter release event; currently it sleeps after five seconds. This will be a key feature of the mutetater and a more complete intervalometer-- using a button or a DS1337 clock alarm to wake up when needed.

Files:

Minimalduino v.89 Delivered

2010-04-08T23:23:00.000-07:00

Three copies of my latest Minimalduino design (V .89) arrived today, fabricated in the DorkbotPDX circuit board order. I built one with all components and it works perfectly, with the exception of the 3.3V regulator having a different pinout than the 75LXX part I used in Eagle-- oops...

A SparkFun protoshield and Adafruit motor shield fit on top fine, but with very little (read: "zero") clearance over the tall capacitors I used-- they'll get some tape on top, and the next revision will use shorter caps or orient them sideways. Excited to work with my first factory-made board, I shot and posted some build pictures with a few notes.

To correct in the next revision:

Fix 3.3V regulator (MCP1700-330) pinout,
Lay out for wider/shorter or horizontal voltage regulator caps for better shield vertical clearance.

To add/improve in the next revision:

5V/3.3V switchable with a jumper on three pins (though it will limit power),
Top pad and through holes under 7805 for better heat dissipation,
Credits (CC, author names) on bottom silk screen,
Optional resettable fuse?
Optional on/off switch or jumper pins?
Try to reduce the number and length of jumpers.

New(ish) "Official" Arduinos

2010-03-31T13:08:00.000-07:00

The Arduino FIO, announced at the New York Uno Punto Zero meeting, is Shigeru Kobayashi's Funnel I/O board, now officially in the Arduino stable, manufactured and sold by SparkFun Electronics ($25). It runs at 3.3V, at 8MHz, and includes voltage regulation, a LiPo charging chip, and an XBee socket. Note that the USB connector is only for power, not for programming.

The Arduino Nano 3.0 by Gravitech ($35) got a lot of press in the last week after being stocked in the Make: Magazine Maker Shed (though it was actually rolled out in July). This revision has LEDs for power, RX, TX, and D13; auto power sensing; power regulation and USB programming interface-- pretty much everything a full-sized Arduino has, plus the two extra analog input pins available on the smd ATmega328.

Both are listed on my comprehensive Arduino-compatible boards spreadsheet. I find it interesting that neither of these conforms to the original Arduino form factor, which makes sense given how little space smd components occupy and how often auxiliary circuits are built on solderless breadboards. Still, breadboard tinkerers miss out on the awesome functionality built into shields, which was the motivation behind the Minimalduino board.

Minimalduino: Three, Please!

2010-03-29T17:12:00.000-07:00

I got the latest version (.89) of my Minimalduino board to Laen at DorkbotPDX before the deadline this morning-- looking forward to getting three copies of it!

I met all of the specs I laid out in my original post, except there are no TX/RX LEDs and no SPI header. Keeping it exactly the same size as the Diecimila/Duemilanove meant more (and longer) jumpers than I wanted, but I like the layout over all, and the jumpers won't matter for the DorkbotPDX order since those will be 2-sided boards.

My favorite features are the button type options (top or side), power connection options (barrel or screw terminals, plus .1" separated pins), I2C header, and extra standoff mount-- the three Diecimila/Duemilanove standoff mounts never seemed adequate to me.

Motoruino

2010-03-19T10:40:00.000-07:00

Guilherme Martins announced his fantastic "Motoruino" (flickr set) freeduino board on March 9. It has a shield-compatible pin layout, power pins for each Arduino pin, and a L293D motor driver circuit on the right side. I like that he didn't bind the driver to any particular Arduino pins and included three ways to attach motors' leads. I can't wait to get my hands on one.

PPAC Fixes, Minimalduino, Timer

2010-03-16T12:37:00.000-07:00

I've been busy lately and haven't had as much time as I'd like to tinker, but I've gotten things moving in the last two weeks and am overdue to post.

Hoping to show off the alarm clock a little, I brought the PPAC (including power block, valve tree, and tank) to the Make:SF Meetup last month, and while talking and hooking it up at the same time, plugged the AC supply into the DC power socket! The voltage regulator fizzled but the power board seems fine otherwise. Strangely, of all things, the LCD display was dead as well... though I may have killed it when disassembling the can..:o I ordered a better looking LCD replacement which I'll install in the next few days-- green-on-black instead of black-on-green: Newhaven NHD-0216K1Z-NSPG-FBW-L.

The minimalduino project is still moving forward: I'm using a test board I made at home a few weeks ago, populated with as little as possible: chip, caps, resonator, female headers, reset and male FTDI header. I'll move a few traces around but it's pretty much there, and hope to get three test boards made through the DorkbotPDX PCB order, deadline noon on March 29. I've built a spreadsheet with costs, and it seems like I could make a batch of 25 kits at just under $15 each. I'm not sure if it's worth the trouble though.

A few weeks ago, I built a new coffee grinder timer with a re-worked sketch and single board, then handed it off to fellow coffee fiend HF for ideas on how to make the ideal grinder timer. One thing we agreed on is that tenths of a second would be cool, so last night I had a great time working out a sketch to drive a common anode 3-digit 7-segment display using an SAA1064 IC. Of course having a sketch to start with made things straightforward-- thanks Alessandro Saporetti! I reworked the code to make it more general purpose, using all of the chip's functions including multiplexed (versus not) and changing the constant current output (7 output levels possible, from 3 to 21mA). [Video to come]

100K Views!

2010-01-03T18:36:00.000-08:00

The PPAC "Inflation" YouTube video had its 100,000th view today-- wow! Thanks, viewers!! The big spike happened on December 14 when it started showing up on my favorite blogs, and it has been getting >1000 views a day since then.

Here it is again:

Also, the first "ejection" video:

Minimal*duino

2010-01-03T14:22:00.000-08:00

I reworked the one-layer board to got everything routed nicely in two layers, and etched it last night with the layers very well aligned! Now to get flux-- without it, the vias need their own little lead, which is quite a pain. I'll build it out today and test it, then look at board house prices for making a minimal order, seeing how many I'd have to order to get the price down to $10/kit (with no extras). I wonder about rebuilding it in KiCad though-- I've about had it with EAGLE's inefficient UI.

Mute-tater lives!

2010-01-03T13:59:00.000-08:00

I've been working on the mutetater program and board, and have it mostly sorted out, including the bulk of the mounting details. I etched a small 1-sided board to hold my old Arduino Mini, with transistors rigged like the TV-B-Gone v1.2, and headers for four LEDs, a button, ftdi programming cable, and 5V power. I'm using a Bodhilabs "VPack" with a single cr2032 to get 5V, and its header works nicely for mounting a power switch. It all fits in the foam potato, so now to figure out the button and LED mounting.

Minimal Arduino?

2009-11-28T05:49:00.001-08:00

I prefer breadboard-friendly Arduino-compatible boards like Boarduino and iDuino, but I keep wanting functionality people have built into shields like Adafruit's Motor Shield and Batsocks' TellyMate Shield.

All I want in an Arduino:

ATmega328
FTDI programming header
Arduino "form factor" with odd D7/D8 spacing and standoff holes

Sorting my Arduino-compatible board spreadsheet first by price, then by form factor, it seems the lowest price for a shield-compatible board is ~$17 for a serial Freeduino, compared to ~$10 for a Dorkboard, though the latter comes with an ATmega168, not a 328.

Necessary items:

microcontroller: ATmega328, socket, capacitor
clock: oscillator and 2 caps, or a resonator
reset: 90-degree (side) button, 10K resistor
FTDI cable interface: 6-pin header, capacitor
Power: Barrel connector, 2-pin header

Extra interface header pin pads:

icsp (2x3)
i2c (4)
~~spi (6)~~ (nah)

Simple extras, parts not provided:

Power indicator: LED, 1K resistor
TX/RX indicators: 2 more LEDs, 2 more 1K resistors
Power regulation: 7805, 2 capacitors, jumper
Diode to prevent inverted power hookup

I'm traveling for the next month so this will be a fun little layout project, perhaps as a way to learn kicad (as opposed to EAGLE, which I currently use) and to explore board house pricing and specs. The goal is to be able to produce a $10 kit (cost), which may be possible given how many goodies SparkFun includes in their $20 Arduino Pro 328.

Update 12/29: I got a single-sided board laid out with just four jumpers, and I'll tear it up and redo it with the programming header where I want it, jumping TX and RX across the board. The files for the "Severino" single-sided board helped me figure out the routing.

PPAC Demo Video

2009-11-18T00:26:00.000-08:00

The inflation feature demonstrated with the bed unoccupied:

(Sorry for removing the original video, but... I promised Liz I'd remove it!)

Getting Out Of Bed: PPAC Major Components

2009-11-17T17:24:00.000-08:00

The "Princess and the Pea Alarm Clock" (PPAC) has been working beautifully, waking me up with "buzz" alarms and literally getting me out of bed with "inflate" alarm functions! I will post more photos and videos soon, but first to outline the alarm clock's major components:

Alarm clock: LeSueur peas tin can containing the main circuit board, jog/shuttle dial and button input, 16x2 character LCD display, modular handset cord jack, and female 6-pin FTDI cable jack.
Power block: Power input/output circuit mounted in a plastic iPod Nano box, with input DC power jack and regulator, relay input power jack, two relay-switched output jacks, modular handset cord jack, status LEDs, and main power switch.
Valve tree: Brass and plastic fittings around the main trigger solenoid-controlled sprinkler valve, with quick-release fittings on both ends, manual safety valve before the trigger valve, and manual release valve.
Air pressure source: 10-gallon (red) or 5-gallon (yellow) air tanks, both with pressure gauges and female quick-release connectors, usually filled to 110-120psi.
Air bladder, aka "Pea": Green exercise ball between my mattress and box spring, with a hose ending in a male quick release fitting.

Silly Alarm Clocks

2009-11-16T21:54:00.000-08:00

I've been bookmarking funny alarm clocks for a while-- snoozing is so universal, and I get a kick out of the features people choose to include in their wake-up devices to ensure that they actually get out of bed. While not Arduino- or ATmega-based, here are a few of my favorites:

Clocky news popped early 2007, and it took me about a minute to place an order-- had to have one as soon as possible! It was too easy to just turn on its side, though, with the side of a tire as the base, so it spins around on my night stand instead of taking off. Cones on the end might prevent that, but I still love it, and it got me thinking seriously about my old inflating alarm clock idea, so is probably the single biggest inspiration for the PPAC.
The Pneumatic Bed Shaking Alarm Clock was built for Toronto's "The Edge" 102.1 "World's Biggest" contest and while it seems too violent to be used every day, its maker claims to have used it to get up for four years! This may be the epitome of taking a silly alarm clock idea too far, and I have nothing but the utmost respect for its maker.
The Perfect Wake-up Machine, a design project by students a Colorado State University, assaults all senses with its control of just about anything. Serial communication, a few PIC chips, and multiple power systems combine to make a beast of an alarm clock-- kudos for overkill!
"The World's Loudest Alarm Clock was a simple but effective build by Kip Kedersha (aka "Kipkay"), replacing a cheap alarm clock's speaker with two sirens for a deafening wake-up experience. Like The World's Biggest Alarm Clock, I can't see this as something anybody would want to use a second time!
Alarm Clock/Bedpost "-MAWD-" is an odd refitting of an alarm clock, lamp, and speaker into a tube attached to a bedpost. Most notable for being the product of a one-night, I'll-do-it-right-now!-inspired fit of tinkering, it has "silly hacker" written all over it. I love the tangle of wires supporting the LCD.

4-Way Button: Click, Double-Click, Hold, Long Hold

2009-10-13T09:47:00.000-07:00

How many ways can a button be clicked? [Anonymous] commented asking about double-clicking after my "Click for A, Press and Hold for B" post, and I finally got around to it, adding a long hold function too. Last night I tidied up the code and debugged obscure outlier cases, and the result is a simple 4-way button function which can report click, double-click, hold, and long hold events.

When used with a rotary input (pot, rotary encoder, jog-shuttle, etc), complex branching menus are easy to implement. Note that the long hold event always triggers a "normal" hold event first, while single- and double-click are completely independent (as well as being independent from the hold events).

I've posted code in the first two comments-- the tabs of my test sketch, with the second comment containing the checkButton() function. This seems like a good candidate for my first proper library; I would appreciate any help in getting this example sketch converted into an easily instantiated object, like AlphaBeta's Button library.

Strobit Wireless Camera Trigger

2009-09-10T08:39:00.000-07:00

Stephen Eaton has been working on a wireless, low voltage Arduino for camera trigger applications: Strobit. After a call to geekdom in 9/2007, the project has gotten to the point that boards have been manufactured and are being tested.

The project page at Gcode has lots of information, there are photo sets on Flickr-- board development progress and some photos taken using prototypes-- and an Arduino Forum thread with a few questions answered. I continue to be impressed by the level of sophistication people have been putting into their Arduino-compatible boards.

Illuminato X Machina... WOW!

2009-08-21T19:20:00.000-07:00

From the folks at Liquidware who brought us the beautiful Illuminato Arduino variant and numerous shields comes the (ahem) WTF?!-board Illuminato X Machina (announcement here), described by Wired writer Priya Ganapati as:

"...a motherboard prototype that uses separate modules, each of which has its own processor, memory and storage. Each square cell in this design serves as a mini-motherboard and network node; the cells can allocate power and decide to accept or reject incoming transmissions and programs independently. Together, they form a networked cluster with significantly greater power than the individual modules."

The small board, cleverly sold alone or in 4-, 9- and 16-packs aims to be a different model for computing hardware, with power and data I/O on all four sides, and while it's hard to imagine applications, it's an impressive example of the power of open source hardware and clever design.

PPAC Progress: UP!

2009-07-19T23:17:00.001-07:00

I've been working on (mostly) minor tweaks to the alarm clock:

The can I had used to test mounting techniques served its purpose as a prototype, so I redid the mounting in a fresh can, with adjusted positioning of the LCD and (new) lit button, with use three screws per end cap instead of two. I scanned the LeSueur label and printed a copy to test the positioning of the LCD, button, and power/relay port cutouts.
I over-tightened the plastic ring which opens the output valve of my 10-gallon air tank, leaving me with a sealed can at 105psi! I bought a 5-gallon tank as a replacement, figuring it would be fine for a full run, and was impressed by its lightness. I "fixed" the 10-gallon tank's valve by cutting off the plastic ring, so I can turn the open/close with a small wrench, so now have 15 gallons to pressurize.
Testing the 5-gallon tank at 100psi, the plastic "open" safety valve popped a leak, so today I replaced all pre-solenoid valve hardware with brass-- no more leak!
Since the emptying valve didn't get enough pressure from the inflated "pea" to open, I replaced it with a manual valve-- not as elegant, but the alarm is about inflation, not deflation.
The alarm was still triggering when the alarm was "off" and the target time was reached, plus there were a few small bugs to work out.
The maximum inflation time was set arbitrarily at 30s, so I added another click+hold "hidden" mode branched from the alarm mode selection so the max inflate time can be adjusted. It's also stored to (Arduino) EEPROM with other "system" parameters.

The IDE tells me I still have a little headroom:
"Binary sketch size: 13566 bytes (of a 14336 byte maximum)"
I'm tweaking the program a but more, but it's late and I'm so happy with how far it has come! I plan to be woken up rudely in the morning...:D

LCD difficulties

2009-06-16T15:21:00.000-07:00

After putting together a schematic in EAGLE for the shower control circuit, I tinkered a bit trying to get a scrounged Powertip PC1602-G character LCD working. Serial LCDs from SparkFun are easy to use but expensive, in addition to hogging the serial port and being available only in 16x2 and 20x4; I'd like to be able to use cheapo 8x2 or other displays.

I soldered on a pin header and got to breadboarding it with an iDuino, but quickly discovered that the tutorials are pretty haphazard, and I wasn't able to get any output using the LiquidCrystal library in spite of quadruple-checking my schematic and breadboard connections.

I tried Limor's tutorial but got no result, and I think editing the library to set the pins is an odd (wrong?) way for a library to work. I even used the exact same pins-- no dice. I wonder if the scrounged LCDs I'm using have custom commands that makes them incompatible with the library-- I need to try a different LCD, and maybe use Massimo's raw example.

Update: In a comment, Al asked if the LCDs I was trying weren't HD44780-compatible at all and... oops, thats the problem! I got it working fine with an LCD scrounged from an old Brady Labelmaker, which contains an actual Toshiba HD44780.

Xcode > Arduino?

2009-06-06T18:29:00.000-07:00

After bookmarking melka's Xcode Arduino template the other night, it was funny to see it posted the next morning on the Make: blog-- all signs point to Xcode, so here I go. Not having experience with a full-featured IDE or "real" C++ development, it should be an interesting learning experience.

The first thing I had to do was get the latest Xcode, 3.1.2, a 995.9MB download-- I installed 3.0 a while ago, but it complained when I tried to open melka's template. Got it installed, then went through melka's README and... everything worked!

I screwed up the first run through by renaming and moving the project. On the second try, I copied the unzipped "Arduino Base Template" to my desktop as "ArduinoBaseTemplate" and everything worked with the new template in Library/.../Project Templates/Arduino.

All is not wine and roses, though-- a test sketch that worked fine in the Arduino IDE gives me a lot of errors in Xcode, all related to the order I'm declaring things-- I generally define functions after my setup() and loop() calls, but Xcode gives me "was not declared in this scope" errors for all of them. It seems I do need to learn the basics of C++ to get this working. How to get a crash course in this stuff? Google came up with "C++ Language Tutorial" so, more to read...

Alarm Clock Board Built!

2009-05-18T08:51:00.000-07:00

Last night, I finished the board layout in EAGLE and got to work making it:

Turned off layers in EAGLE except layer 1 and pads, and printed to a PDF,
Rasterized PDF in Photoshop at 1200dpi and processed into a black+white image (right),
Laser printed onto an L.L. Bean catalog page, with the print output set to "transparency,"
Ironed onto 2.5" x 2.2" single-sided copper clad,
Fixed gaps with etch-resist pen,
Rubbed off paper and etched in ferric chloride for 15 minutes (though I'll use use the HCL and peroxide method in the future),
Rubbed away ink with acetone,
Tested trace continuity and scraped away tiny bridges with a knife,
Drilled out all holes (1mm bit),
Populated with parts and soldered it up,

Pressed chips into sockets,
Hooked up LCD, jog/shuttle, a button and LED.

It behaved exactly like it did on the breadboard! Now I can focus on the right button/LED combo and casing, ~~redoing the relay board,~~ and tightening up the program.

This is my first from-scratch Arduino-compatible board-- sure to be the first of many...:)

Click for A, Press and Hold for B

2009-05-14T23:43:00.000-07:00

I planned to add a time setting mode to the alarm clock later, as gravy-- thought I wouldn't need one since the clock chip keeps time-- but with the board not yet built, I keep accidentally disconnecting the DS1307's battery and needing to reset it with a special sketch.

That's a pain, so I'm adding it to the PPAC program next, and to keep the interface simple-- jog/shuttle and a button-- a press and hold event seems appropriate for switching into an otherwise hidden mode, like shutting down a MacBook by holding down the button instead of just clicking it.

Despite a few posted examples on debouncing a button press (explicitly or with a library), I couldn't find any press+hold examples, so I took a stab at it and got a test sketch working pretty quickly with a button and two indicator LEDs. The code is posted below, as a comment.

Paperduino, Hifiduino

2009-05-13T10:10:00.000-07:00

Love the *duino naming scheme people are putting on their projects! Fun+easy to create a buzzword that conveys the function of an Arduino-based project. Two projects that have popped up on the internets in the last week that I thought were very cool:

Hifiduino: project blog by The Lazy Engineer chronicling his work to build a very slick Arduino-based hi-fi remote control. I especially like the casing work-- nicely assembled wooden box with its top made from an aluminum hard drive housing; one of the best uses of scrounged hardware I've seen. He has also chosen a lot of technologies I've been exploring in terms of (1) making an elegant interface with a single rotary encoder and display, and (2) using I2C chips for easy interfacing. The blog "extras" on the right are an excellent example of sharing, too, with links to code, examples, references, etc.

Paperduino: an Arduino circuit design by Guilherme Martins for introducing Arduino to neophytes in a workshop setting by having them build one from raw components on a 2-sided color printout. Beyond looking cool, it helps to get over the "soldering is hard" issue (pssst-- it's easy and fun!) and to understand the minimal necessary components to make a working Arduino circuit. Flickr set from the workshop, Paperduino PDF patterns.

PPAC Board V7.3: Hand Routed

2009-05-13T00:03:00.000-07:00

Work on the main board (alarmduino?) is progressing nicely, but not without a false start-- after etching and building out the first board last week, I found that the 5-pin header to mate with the Futurlec DS1307 mini board was backwards! But the DS1307 doesn't need much circuitry, and the mini board had a lot of unused space, so I decided to revise the alarm clock main board with the clock built-in.

The latest PPAC layout has the DS1307 on the right side, with the battery holder on the bottom and interrupt going to A3; I would have tested the schematic on a breadboard tonight but I can't find any 10K resistors. I added an I2C EEPROM too (or, at least a socket for one-- I don't have the little sucker yet) for program settings, maybe a log of wake up times, and relief for the ATmega's built-in EEPROM.

Not to whine, but I'm getting impatient with EAGLE's autorouting for 1-layer boards-- I can usually find a route for the missed connections, and it's annoying to have to push around so many traces to fit them in. This board layout was routed completely by hand after EAGLE kept leaving at least four air wires. It might work as-is, or I may spread into the unused areas and widen the traces. Must resist the temptation to just etch it and build it before breadboarding the whole thing-- I want to have the program ready for this specific circuit, since I shuffled some pins around on the EAGLE layout after converting it from my previous working breadboard circuit.

PPAC Progress: RTC, Jog/Shuttle

2009-04-21T01:50:00.001-07:00

I got my old test sketches working again for the DS1307 clock and jog/shuttle controller, and suddenly everything is working...:) It's "just" a matter of software and hardware layout at this point [gulp!].

RepRap Day?

2009-04-21T00:50:00.001-07:00

4/20 has been a banner day for the RepRap Foundation with the release of the V2.2 extruder controller board and news of the first RepRap-printed circuit board.

The controller includes H-bridges, MOSFET drivers, RS485, thermistor circuit, and lots of little niceties. While currently offered only as a $30 SMT kit, the impressive assembly how-to makes surface-mount soldering look not so scary.

And printing a circuit board is... just astounding! For all the criticism levied against RepRap's claims of (eventual) self-replication, this step says to me that RepRap has real legs-- it's not just an open source 3D CNC platform with an insane goal. The resulting board functions as an optical end stop for a RepRap-- to Rhys Jones, I offer my humble [APPLAUSE]!!!

BrewTroller Brewing Control System

2009-04-09T09:41:00.000-07:00

Excellent project out today: BrewTroller - Brewing Control System. Starting with the Sanguino layout, Jeremiah Dillingham built out a custom 1-sided board with a great interface-- rotary encoder and character LCD display. Nice use of RJ11 connectors for temperature sensor input, plus a 6-pin rotary encoder header and screw terminals for other connections. (via Hacked Gadgets)

Smapler v0001r2 by BlushingBoy

2009-04-08T14:14:00.001-07:00

Smapler v0001r2 by BlushingBoy
Originally uploaded by dcuartielles

That's a lot built-in-- audio out, SD, keyboard port, vreg... doesn't expose pins so is it "Arduino-compatible"? Very nice-- I like blushingboy's stuff.

Prioritizing Projects

2009-04-08T11:32:00.000-07:00

Too many parts and projects lying around-- need to nail down an order and finish something soon!

PPAC should be the first priority-- I've gotten it to work, but attempts at packaging it have been held up by the fact that I'm still not sure about UI and whether I even want to use high pressure air or a pump. Would be great for a contest, but not unless it's (1) done and (2) demonstrated through video. First-things-first time:

EAGLE: set up with display, jog/shuttle, RTC, buttons, switch, power, and output. Don't worry about whether output is to relays or oo's,
Arduino: get a good program working on the breadboarded circuit,
Figure out best fill/empty plan,
THEN start laying it out in 3D for the final build.

Next up (while figuring out ppac fill/empty plan) is a working growduino with relays, no sensing, no logging, and no solar-- don't try everything at once! Better to get something growing.

The invervalometer is so close, but needs:

To be reeled back to the breadboard after the stuffing problem-- Arduino OK?!
Panasonic-capable trigger,
Serious power system consideration.

The mutetater should be a simple build:

Limit to Sony since that's easy to read, and I have Samid's old Sony TV,
Breadboard > potato should be simple using a dorkboard with female header pins.

Comprehensive Arduino-Compatible Hardware List?

2009-03-24T13:50:00.001-07:00

I can't find a complete list anywhere, so here's my stab at it, starting with the list at arduino.cc, Make's 2008 Arduino Gift Guide, Freeduino, Adafruit, Sparkfun, Seeed Studio, RepRap, Wulfden, [more]. Not sure about the Orangutan and mpguino since not all pins are exposed, and unsure of Teensy boards since they need custom Arduino IDEs.

Update (June 16): I revised the spreadsheet and messed around with font and cell sizes to make it more easily viewed in-line here, plus it should update automatically as I add or edit boards. Happy hacking!

Update... ALL THE TIME!: This is constantly being updated as new Arduino-compatible boards are announced!

Click here for the spreadsheet on its own in Google Docs.

Broken?

2009-03-24T08:53:00.001-07:00

After trying to stuff the intervalometer circuit into a jar a few days ago, it just hasn't worked right. LCD goes blank in trigger and shoot modes, and it doesn't trigger the camera, though the serial output is right. The backlight "peek" function has stopped working too.

Using the protoshield on my "proper" Arduino has been too limiting space-wise anyway-- time to transfer to a bigger breadboard with an Boarduino or iDuino to sort things out and finalize the controls and ports in Eagle, plus I'll have room to mess with audio amplifier circuits and FZ20 vs. EOS remotes.

Had an idea about an Arduino variant this morning (in the shower of course) but wonder if something like it has been made already... is there a comprehensive list of *duinos anywhere?

IR receiving success

2009-03-16T21:13:00.000-07:00

Following this example on rtfa.net, I'm reading remote codes from all of my Sony remote controls-- works like a charm! Need to make sense of the Arduino timing code, then I'll try the RC5 example from 5volt.eu.

Update: I programmed all of the codes for my RMT-V203A and even took it apart to put the window back in and to try getting FF to work-- still no good. Found a list of Sony VCR codes and commands, and it looks like that's them, with 1408 added, or 10110000000.

Mutetater: IR work

2009-03-16T13:43:00.000-07:00

I was able to get an IR LED to snap the trigger on my Rebel XT following jaycee's example in the Arduino forum-- pretty simple code.

It looks like I'll need to use more complicated, standard remote control protocols for "mute"-- RC5, RC5X and RC6 come up in searches, and Allesandro Lambardi did much of the legwork programming Arduino to read RC5 signals.

Time to dig through the TV-B-Gone threads at Limor's forums...

Ping... ing... ing...

2009-03-16T00:13:00.000-07:00

Using a bunch of Arduinos for projects, it makes sense to post about it to help keep track of what I'm doing.

Current in-progress projects:

PPAC: Princess and the Pea Alarm clock: "pea" inflates to eject whiny princess (or, um, me) from bed,
Intervalometer-in-a-jar or "intervalomejar": time lapse camera controller with beam break, light level, and audio triggers,
Mutetater: TV mute control with a potato (seriously),
EL-wire suit: audio level meter of EL-wire,
Cheapo general-purpose PID-based temperature controller,
Growduino w/logging, solar power,
Smart shower controller,
[more...]