Remember when I wrote about Cheap Arduinos? Well, if you do, maybe you remember the Diavolino.

The Diavolino is a damn cheap Arduino clone, coming in at about $13. (I say “about” because if you want some headers, or a battery pack, or a chip socket, it’ll run you another few bucks… but still, you can get away with just $13 for the base kit.)

Even though I said there was an “extremely detailed assembly guide” there were a few places where I got slightly confused, mainly just in the “power options” section. (I wasn’t even drinking when I put this kit together, unlike the last kit I built.) Since I got the Diavolino with the 3 x AA battery holder for $1, it was simple to just go with that option. Obviously you’ll need a FTDI USB-TTL cable to connect it to your computer to program it. Again, leaving out the on-board USB makes this kit nice and cheap. (I did get a socket for the chip, as I don’t like to solder chips directly into place.) My only real complaint is that, even though the board looks cool in red and black, it can be a little hard to read the type on the board to locate the correct pins. Then again, I tend to prototype in dimly lit rooms.

I got this kit put together in about 40 minutes. (In fact, I even made a time lapse video showing the assembly.) This seems like a pretty simple kit for a beginner. In fact, I could see the Diavolino being used as a kit put together in a class for people wanting to learn soldering and basic Arduino programming. (As long as you can send them home without an FTDI cable.)

The Diavolino appears to have been designed knowing that in being low cost, a few sacrifices had to be made, and I’m OK with that. If you know how you want to use it, it shouldn’t be an issue at all. (This one is destined for a robot.)


Teensy vs. Atmega32u4 Breakout Board+

Photos from Adafruit Industries.

I remember seeing the Teensy when I was digging into Arduino stuff last year, and it looked interesting, mainly due to it being small and cheap. (I like cheap!) But since I’m a lot more interested in what the Arduino has to offer, I didn’t look into the Teensy very much.

The Teensy is interesting though because out of the box it functions as a USB HID device, which means it can very easily emulate a keyboard or mouse. (See this Awesome Button post for a neat example.)

If you didn’t know, I’m a big fan of Adafruit Industries, not just for their amazing customer service and great products, but for their support of the open source movement, especially the work they’ve done with open source hardware. Adafruit actually sells the Teensy, but they also came out with a product called the “Atmega32u4 Breakout Board+” (terrible name, eh?) which is like a Teensy, but not like a Teensy.

Here’s where it gets weird… or interesting… or both…

By all respects, the Teensy is pretty cool, as I said, it’s small, and cheap, and can emulate a USB HID, and if your project needs that, it’s a good fit. See the Teensy page for more info.

Now, the “Atmega32u4 Breakout Board+” (terrible name) by Adafruit is similar but different. You can check out the Atmega32u4 Breakout Board+ page for more info.

Ultimately, I think I’d prefer to use the Atmega32u4 Breakout Board+ from Adafruit, and for a good explanation, see this Adafruit blog post about the Teensy, and for extra credit, see A Brief Essay About the Benefits of Open-Source Hardware.

It’s a shame the Teensy is not open source hardware, as I’d prefer to support vendors of open source hardware.

So I’ve got a project planned, and it will use a Teensy. So why not use a Atmega32u4 Breakout Board+? The first reason is, I don’t think I’m ready for it. In reading through the Atmega32u4 Breakout Board+ docs and digging through the forums a bit, it looks like Atmega32u4 Breakout Board+ development is not exactly easy for a beginner. I’d like to get into it at some point, but right now, the Teensy seems like an easier path to completing my project, and maybe once it’s done I can look into working with the Atmega32u4 Breakout Board+.

I know this may seem like a small thing, but I’d really like to support open source hardware when I can, the same way I try to support open source software when I can. It’s always a struggle.


Cheap Arduinos (USB)

The last time we looked at Cheap Arduinos we focused on Arduino compatible boards you could put into a project permanently, as long as the project was stand-alone, and didn’t require connection to a computer. (They all used USB-TTL cables/connectors to connect to a host computer for communication/programming. The USB-TTL devices typically cost between $15 and $20, so if you keep one permanently attached to an Arduino, you’ve probably doubled the cost of the project.)

Since the cost of the USB connection seems to be the bulk of what makes an Arduino more expensive, what are our options if we want/need USB on board?

Photo from Adafruit Industries

We’ve previously mentioned the BoArduino from Adafruit Industries (there are two models, one with DC power but no USB, and a USB version.) They just updated the USB BoArduino, and replaced the big USB jack with a mini-USB jack. While this is a kit and needs some assembly and soldering, it’s a very minimal amount.

Adafruit has it for $25.00 + $3.99 shipping. (Occasionally Adafruit offers 10% discounts on kits, so if you’re lucky you could get it for $22.50.)

Pros: Affordable – $25.00, Small, Chip is socketed, “No-Wait” bootloader, USB protection fuse
Cons: A bit more expensive than the other options, Can’t use standard shields

Photo from Seeed Studio

Seeed Studio Depot has two cheap options for you. The Seeeduino V2.2 has an ATmega328 for $22.50 + $3.02 shipping. If you don’t need the 328, there is also a Seeeduino V2.2 with an ATmega168 chip for just $19.00 + $3.02 shipping. Both have non-socketed chips, but the boards are the standard size to accept shields. Both of these are not kits, but come fully assembled and ready to use out of the box.

Now, a few notes about Seeed Studio Depot. They are based in China (if that matters to you) and the “cheap” shipping option does come with a disclaimer saying “10-30 Days.” There are faster/more expensive options obviously, but we’re going for cheap here, remember? They also offer free shipping world-wide for orders over $50. Unlike most other verndors, they do not seem to offer discounts when you buy in bulk.

Pros: Cheap/Affordable – $19.00-$22.50, Can use standard shields, Assembled
Cons: Chip is not socketed

Freeduino USB complete KIT
Photo from NKC Electronics

You want Freeduino? We have a Freeduino option for you… It’s the “Freeduino USB complete KIT” (catchy name!) and like the BoArduino, you will need to assemble/solder it together, though this one will require a bit more work than the BoArduino. Like the Seeeduino, it’s the standard size to accept shields. A nice fit right between the BoArduino and the Seeeduino.

NKC Electronics has it for $22.99 + $4.75 shipping.

Pros: Affordable – $22.99, Standard size, Chip is socketed, “Fast” bootloader, USB protection fuse, Can use standard shields
Cons: Kit needs to be assembled, Vendor/web site does not seem as “big” as others. (This may not be a con.)

Since we’re talking cheap, our friends at Modern Device have what they are calling “Vintage Italian Arduinos” on sale for $24.95. (It’s actually an older model of the “official” Arduino, the Duemilanove. Not bad for a 100% compatible full-sized real Arduino with USB.

Again, if you are just starting out and getting your first Arduino, you really can’t go wrong getting the Arduino Uno, which costs $30 and comes fully assembled and ready to use. In fact, many vendors offer “starter kits” which include breadboards, sensors, jumpers, books, and other “nice to have” things for beginners.

For projects where you want a cheap Arduino always connected to a host computer via USB, these options may fit the bill. I’ve ordered one of these for a project, and once it arrives I’ll post a bit more info about it.

I also wanted to call out my only “con” for the Freeduino board from NKC Electronics. Vendor/web site does not seem as “big” as others. As noted, this may not be a con. In a future post I’ll talk a bit more about this, and the various places you can get an Arduino from. Until then, keep on hacking!


Cheap Arduinos

As I continue to explore the world of Arduino, I started looking for cheap Arduinos to use in projects – permanent projects that need a dedicated microcontroller. Once you’ve got an Arduino and start having fun with it, you think about things you can build, but you always want one around for prototyping and trying out new ideas, so for permanent installation, you’ll want a cheap Arduino you can drop in place.

Now, since Arudino is open source hardware anyone could get the parts themselves and assemble and use/sell an “Arduino-based” board. This is great, and it’s why I love open source, and it provides many choices. That said, if you are not the “build your own from scratch” kind of person, keep reading for some kits that may work for you.

These are the cheap Arduinos I found, with some notes on each. All of them require some sort of of FTDI connector, as they do not have USB connections. This is fine for boards that will find their way into projects that do not need to be connected directly to a computer, the idea being, you buy one FTDI connector, and you can use it to program all of these boards. Each vendor should also have an FTDI connector for sale, for instance, SparkFun’s FTDI Basic Breakout 5V, Adafruit’s USB FTDI TTL-232 cable, etc. (You will need to figure out the whole 5V or 3.3V thing.) Also worth mentioning is that most of these are kits, which means you’ll need to be comfortable soldering small pieces to make them functional. (Shipping costs you see below are typically estimates, with the choice of the lowest cost.)

Photo from Solarbotics

Ardweeny probably wins the prize for smallest Arduino, as the “board” and the components actually sit on top of the chip! It’s a novel idea, that’s for sure. If you want a super-cheap Arduino to plug into a breadboard, this is it.

Pros: Cheap – under $10, Very small
Cons: You can’t replace the chip*, so if it gets blown, you’re out of luck, No easy way to power it, Requires FTDI to program it

Now, if you want to “free your Ardweeny from the breadboard” you can get an Ardweeny BackPack which provides power, and a few other niceties. It’s $11.95, which makes teaming it with an Ardweeny total more than $20, which doesn’t make a ton of sense to me… It’s a neat idea, but it all seems a little weird.

Maker Shed has it for $9.95 + $6.95 shipping and Solarbotics has it for $9.95 + $6.94 shipping but note that Solarbotics has a $5.00 “handling fee” if you place an order under $30.

Photo from The Makerspace

PicoDuino is another small Arduino. I don’t know much about “The Makerspace” and their web site doesn’t really provide much info on them. I do like their description of the product “We designed the Picoduino to be small, cheap, and disposable so that you can throw it in a project and forget about it.”

Pros: Cheap – just $10, Small, The chip is in a socket, so it is replaceable
Cons: No easy way to power it, Don’t know much about “The Makerspace”

Similar to how the Ardweeny has it’s backpack, the PicoDuino has it’s PicoDuino Shield Adapter, which makes using it in a more traditional fashion a little bit easier. The adapter is $10, same price as the PicoDuino itself.

The Makerspace has it for $10.00 + $5.00 shipping.

Photo from Modern Device

Really Bare Bones Board (or RBBB) is a step-up in the small/cheap Arduino world. It’s got an easy to connect power jack, a socket for the chip, and the board itself is a bit “customizable” as far as the size you want it to be.

Pros: Affordable – under $13, Power jack, Customizable board size, Chip is socketed
Cons: Still need an FTDI connection (maybe)

I really like the specs of the RBBB. Also note, you can buy one fully assembled for $22.00 if that’s more your style.

Modern Device has it for $12.95 + $4.00 shipping, and The Shoppe at Wulfden has it for $12.00 + $2.00 shipping.

Photo by ladyadaSome Rights Reserved

BoArduino comes from Adafruit Industries, and looks to be pretty similar to the RBBB with perhaps just a few more niceties and features.

Pros: Affordable – $17.50, ICSP header, “No-Wait” bootloader, “protection” diode
Cons: A bit more expensive than the other options

Adafruit has it for $17.50 + $3.99 shipping. (Occasionally Adafruit offers 10% discounts on kits, so if you’re lucky you could get it for $15.75, which would just get you in under the $20 barrier including shipping.)

(Note that Adafruit also has a USB version of the BoArduino, which swaps the DC power jack for a mini-USB connection and comes in at $25.00)

Arduino Pro Mini
Photo from SparkFun Electronics

Arduino Pro Mini comes from SparkFun Electronics and it’s damn small. In fact, it’s miniature! It’s also not really a kit, as it comes assembled (you just need to add header pins.) The chip is surface mounted, so it’s non-replaceable. Again, size is the #1 feature of the Pro Mini.

Pros: Affordable – $18.95, Small, Really Small
Cons: More expensive than the other options, non-replaceable* chip

SparkFun Electronics has it for $18.95 + $4.41 shipping. (That’s the 3.3V version. There is also a 5V version.)

(Note that SparkFun also has the Arduino Pro which is just a dollar more, and comes in 3.3V and 5V versions as well, but at almost $20 and a surface mounted chip, I’m not as interested in this one.)

Photo by Windell H. Oskay, www.evilmadscientist.comSome Rights Reserved

Diavolino comes from Evil Mad Science, and it’s red, and has flames. The Diavolino does not come with a socket for the chip, so add another $1.50 or so if you want one. As for power, you can get a battery pack for an extra $1.00. There’s an extremely detailed assembly guide which I think any beginner would be comfortable following.

Pros: Cheap – $13.00, Nice power options
Cons: Large, No socket included

Evil Mad Science has it for $13.00 + $5.55 shipping.

So that’s my quick rundown of cheap (non-USB) Arduino boards. It should be noted that almost all of these get cheaper as you buy more of them. For instance, the RBBB is $12.50 for one, but just $9.50 each when you buy 10 of them. Also, while it makes the most sense to use an FTDI cable to program these, for any of the boards that use a socketed chip, you should be able to pull the chip, put it in a USB-equipped Arduino, program it, and then return it to the non-USB board. In theory anyway… Note that I also didn’t really talk about what model these are based on, most appear to be based on the Duemilanove or the slightly older Diecimila. How you use it will determine if this matters much. All boards mentioned use the ATmega328, though many show outdated photos with older chips on their product pages, so always read the specs!

And if this isn’t enough, take a look at the spreadsheet of many more Arduinos, which may be slightly dated, but is definitely a nice long list.

(Update: When I say something is “not replaceable” it may be better to say “not easily replaceable” at least by a beginner. — Thanks to Milwaukee Makerspace for pointing this out.)