The RRRRRRRRRRBBA, a $3 Arduino

Hey, we all LOVE the Arduino, and for my projects I make extra sure that I used the Arduino platform, so that everyone in the artist and hacker community could springboard off it for their own projects, and so that I can springboard off them. Its so universal and easy to learn!   But,  there are a few things THEY don't want you to know about the Arduino:

Starting with the SHOCKING REVELATION THAT....

Step 1: For a microcontroller, the Arduino is NOT CHEAP!

1. the Arduino is NOT a cheap microcontroller!

When Arduino-lovers like me say "Wow, the Arduino is such a cheap microcontroller!" this is not strictly true -- it is very cheap for what it is, but type "microcontroller" into Mouser's search box and you will find microcontrollers that cost 30 cents, not 30 dollars.

thats because....

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Comments

[jackzylkin]

Good Suggestion! I added a schematic on step 7.

[JesusGeek]

If you buy from Tayda Electronics, you can only spend about 5 bucks to make a fully functional Arduino!

[ptorea-villegas]

"This is not a big deal unless your application needs very accurate timing or needs to perform tasks very quickly -- in which case you can add a crystal oscillator and two capacitors to make it run at the proper 16MHz speed."

In regards of this quote from the tutorial, can the ATmega chip be clocked by a faster crystal, say, 40MHz, or is 16MHz the limit? Thanks!

[VirtualBoxer]

My dad told me that overclocking can mean overheating. So you can, but you'll need the proper cooling.

[VirtualBoxer]

Also, the limit is actually 20MHz for Mega168 and Mega328. (Arduino boards that take a microcontroller with the Mega8 footprint run at 16MHz because that is the limit on Mega8.)

[Ghyorn]

1 atmega8-16pu = 1$
It's the same thing than an arduino but it only has 8kB of flash, bust trust me, it's enought for most of you projects. I have a bunch of them and put them everywhere.

[ponynicker53]

Personally I find it much easier to just make a chip w/ a 16MHz clock and be able to put any old boot-loader on it. I like using optiboot, a sketch that allows you to use your arduino (I use an uno) to bootload a chip. Then you can just stick that chip in the arduino to program.

The cost isn't that much greater:
ATMEGA328P $2.24 
Crystal 16MHz: $0.46 
(2 )Ceramic Disc Capacitors 22pF: $0.22
Optiloader: free sketch
Total: $2.92 for a 16MHz microprocessor running standard arduino bootloaders. Can be bootloaded and programmed w/ a $30 UNO.

Now I just want to find a cheap battery solution. I wish they sold 5V a dime a dozen like AA. If anyone knows of anything let me know. I'd prefer to just have to hook it up w/o any other wiring.

[ponynicker53]

Scratch that, 8 cent capacitors

[ponynicker53]

Would three 1.5V batteries for a total of 4.5 do the trick?

[misellers]

OR you could use Picaxe chips which start at £2 $3-$4 and all the work is done for you. Picaxe were even selling of their 28X2 module for £6ish.

http://www.techsupplies.co.uk/epages/Store.sf/en_GB/?ObjectPath=/Shops/Store.TechSupplies/Products/AXE200

[justbennett]

Yay for Picaxe. I really feel it is under appreciated. It can do many of the things I see people using Arduinos for at a tenth of the price. The programming is easier to learn, and they come in lots of sizes. I encourage everyone to do at least one Picaxe project just to understand the difference.

[VirtualBoxer]

I have designed a Picaxe-based Arduino clone in Fritzing. It is named the Emperor board.

[VirtualBoxer]

The PIC10F200 does cost less than $1, but it still costs over $1000 to buy a full reel of them from Mouser.

[jackzylkin]

That is true, but buying a single one costs 50 cents. Fun fact: to perform the same function, It is actually cheaper to buy a pic10f200 than to buy a dual 555 timer!

[VirtualBoxer]

Dual 555? It is more often called a 556.

[ZachyKras]

i'm pretty new to electronics, but i've been thinking about getting an arduino a lot lately. I've done some research and this is the answer to a lot of my questions. thank you so much! do you think you might be able to add a little schematic about where to include the crystal and capacitors when you move the chip to its project? thanks for making a great instructable for beginners like me!

[RayBurne]

As a longtime microcontroller user, it would recommend that anyone wanting an Arduino buy an Arduino. Then you can learn by using all the tutorials that actually match the hardware that you have purchased. The single chip will just frustrate you if you are not experienced.

- Ray

[bogdanfirst]

You really reallly really shouldn't omit the 100n capacitor. At least one just under the micro.

Other than that. let-s not forget arduino is the one that started the fashion of low cost dev boards.

(from someone who never used one, just AVR micros).

[Krayzi99]

*gasps* *clutches chest* *falls on floor* OMG THANK YOU! I AM SICK AND TIRED OF BUYING A NEW ARDUINO EACH TIME!!!

[GASSYPOOTS]

make your own reset!

[Computothought]

PC interface schematic available?

[PaNiCPeRCePTioN]

N'est pas difficile! C'est très facile! Haha. No...spellings a pain sometimes ;)

[THEORANGESNOWFROG]

Thanks for the nice instructable

I was wondering why the second GND (pin 8) was'nt connected... I'm working on a board with a SMD atmega328 with 2 GND and 2 VCC and I really don't know what to do... Please help!

[dog digger]

Chip where I live cost $24!!!!!

[kiwijor]

Hi, I suggest the DorkBoard as an alternative, easy to assemble, small footprint, super easy to program, just Google for it "arduino Dork Board".

[dustinandrews]

Thanks for this great, thought provoking article. This article got me to wondering what a really small and basic surface mount Arduino Compatible would be. So, I designed one. http://www.instructables.com/id/Make-your-own-1x1-22-IO-pin-Ardunio-Compatible/

[XCVG]

The part about needing the AVRISP to program the chip initially is not strictly true. The ArduinoISP sketch can be used to burn the bootloader using your Arduino! Of course, you need something else to put the target microcontroller in, which is why breadboards were invented. Alternatively, this can be used to solve the infamous programmer chicken-and-egg problem. I built a USBTinyISP clone using this method.

[mad_b]

Congratulations for the good work! I suspected about that, but for an easy start I bought an Arduino 2009 to play with. Next steps will be easier (cheaper), even with 8MHz :-) (My first computer was a 4.77 MHz PC...) hehehehe. Thanks, man

[joshnosh]

i use an uno for playing around and testing. then i use it to program the chip and put it in my project. all you have to do is use ic sockets so you can reprogram it. you should use sockets anyway.

[useraaaaa]

PLZ create simple instructable
"how to make blinking LED"
without arduino
for $3

[killersquirel11]

Try this (originally posted here)
Under one dollar if you know where to look.

[esstein]

... and one video with this RRRRRRRRRRBBA working would be very helpful! Great article, thanks.

[ipfone]

Whit a 16 k ressonator you don´t need the capacitors and you can run at normal speed.. so all your scripts will run with no problems. Don´t forget that all arduino ide uses 16 mhz and not 8 mhz....

[bmlbytes]

The ATMega chip will run on a 8MHz crystal though, it will just process information slower.

[cmiklos]

Agree.. but the problem is the arduino IDE .. not the fact that it does run or does not.

[A.O.D]

This might be a silly question, but one thing I wasn't quite clear on was whether or not I need to connect the crystal to the ground.

[bmlbytes]

No the crystal itself does not get connected to the ground. The crystal is connected to the pins on the ATMEGA chip, and also to the capacitors. The capacitors are connected to ground, but the crystal itself is not.

[gtoal]

A quick followup on this... I ordered 10 from avnet earlier this week and they were delivered today. They have hundreds in stock and no limit per person. Total cost including shipping and tax came to $54 for 10. At that price you can embed the devkit boards in your projects rather than have to make your own PCBs.

By the way Avnet also seemed to offer a coupon (free shipping for TI parts prders over $20) but it's broken. But $8 shipping regardless of whether it's one package or ten is pretty fair.

[marcosf63]

Very good article. Congratulations!

[maclover00]

Please do yourself a favor and get chrome, firefox, opera, anything other than ie7.
There more compatible with HTML5 and other fun stuff(like processingjs)

[kyle brinkerhoff]

DOI! you need a 16 mhz oscillator if you want to preform any i/o functions using the default librarys because ALL OF YOUR I/O WONT WORK! because if you use the internal oscillator you have to be aware of it in your code, also not to mention that the internal oscillator in the atmega chips are limited to strictly internal use of the chip SO! if you attempt to do communication between digital devices you wont be able to use the oscillator to sync your communications between components!

[FrozenFire]

..how about setting it to 8MHz by clicking "Lilypad 8MHz"?
And most communications don't require all chips to run at the same speed or to share the same clock. Just a clock for the bus itself sometimes.

[jackzylkin]

Read Step 7. Btw the I/O will work just fine. The only thing that won't work is asyncronous serial transmission, which you can fix with one line of code -- by declaring Serial.begin(19200) instead of Serial.begin(9600)

[flynnguy]

Who are THEY? From the arduino site:
"Arduino is an open-source electronics prototyping platform..."

The only mention of microcontroller on the site is where they reference the one "on the board." It's also all open source, hence all the arduino clones out there. It also comes with a USB connection to talk to the chip so you can output information to your computer, comes with a barrel plug for external power and other things.

When I first started I looked at the Parallax, PIC, AVR and Arduino. Yes, straight AVR is cheaper but to be as robust as the Arduino, you'll probably end up spending about as much (if not more) by just buying an Arduino. Also I thought it was pretty common knowledge that you could do what you describe though I'd probably throw in a few more things (like a crystal) on most of my projects.

[FrozenFire]

Let's see, an Arduino, once - $30. (actually I got mine as a present)
Voila, an ISP programmer, always-handy USB to serial converter and easy quick prototyping environment.
Hook up fresh AVR to power, hook up the ISP lines to the Arduino, program it to use the internal 8MHz clock without the /8 divider setting.
If I want to upload things to it, I can use a $5 USB to serial cable - or I can just use my Arduino once again. Set the Arduino IDE to Lilypad, upload.
You can even use the FTDI chip to program a fresh chip inserted into your Arduino.

If you have a single bootstrap chip that already has the Lilypad bootloader (or the normal Arduino one and a crystal) or an FTDI breakout (they're $5-ish these days anyway), you don't even need the Arduino.
$8 for an Arduino basically - maybe $10 if you include support components. That's $5 per Arduino if you reuse that very same USB to serial device.
Yup, you're getting 5 Arduinos for the price of one. A little less if you want them to run at 16MHz - you'll need a crystal for each.

[blarsen06]

I bought the basic nerd kit from http://www.nerdkits.com/store/

It's a bit pricey at $79.99 ... and you could probably pick up the parts for less than half that...but their documentation, code samples, etc are all a very big help to a beginner like myself...

• The kit includes:
• Solderless breadboard
• ATmega168 Micro controller
• LCD screen
• Programming cable (USB cable pinned to serial cable)
• The NerdKits Guide
• ...and a bunch of parts (to build some basic projects)

The instructions were really good...and it gives a really good intro into electronics...and a basic intro into C programming.

My first project was a digital thermometer of sorts... that reads out to the LCD screen that it comes with...

I've been considering the Arduino until I realized myself that the chip is the exact same thing that came with the Nerdkit ...and I have everything I need to get started...and that the Arduino just gives you a simplified interface to the controller....which is just extra bloat if you're building something in a small package...

Good article... thanks!

[octopuscabbage]

This could be usefull for just buying one arduino board and then buying like 5 microcontrollers so you can just program them all from one board.

[kikiclint]

oh and the USB 2.0 to CP2102 Module TTL UART 6PIN Serial Converter I have is about $6 off of ebay. 

[octopuscabbage]

Is that just a usb out?

[kikiclint]

yep, it lets you communicate serially to 2 pins.

[octopuscabbage]

Cool - Thanks.

[sephiroth67]

I thought that was always the idea of the thing...you just buy the expensive arduino, then slap the ATmega on a cheap PCB and order a batch of ATmega chips...

[kikiclint]

you can get a usb to serial converter to hook to the serial pins to program it is circuit. Also there is a sketch and circuit to use an already bootloaded arduino chip burn the bootloader to an unburnt chip. Easy. and saves some money by not paying others to burn it for you.

[bill.stewart]

Yup. You're either going to have to buy some kind of chip-programmer for $25-50, or else buy an Arduino for ~$30 which you can then use to program other chips with. The new Arduino Uno is a bit USB-friendlier than its predecessors, or you can get some of the cheaper Arduino clones and use them. If you're a random hobbyist like me, maybe the Arduino's all you need, and it's certainly a friendly way to get started - if you get into complexities like the tiny chips or the surface-mount stuff some of the professional programmer boards can have advantages.

(Also, isn't the chip a bit happier if you also ground Pin 8? The drawing's prettier if you don't, but on a breadboard it's just another jumper wire.)

[sephiroth67]

That's a good question, removing the ATmega from my arduino, I ripped off pin #8 xD

[josh1324]

Its «Ceci n'est PAS une microcontroller»

srry, french grammar nazi

[Cheesyvee]

That may be correct.
Wouldn't Italian be more appropriate though?

[josh1324]

that is very true. Italian would be more appropriate.

[reaman4ever]

Is the setup different with the atmega328? I can't get it going without a crystal.
thanks

[jackzylkin]

Yes, if you are not using the lilypad bootloader, you must manually change the fuse settings on the arduino to use internal oscillator.

[zgr95]

did you change the fuse bits on the chip so it will use its internal oscillator??

[jackzylkin]

Please see the note I just added. Sorry for the aggravation this may have caused.

[zgr95]

http://arduino.cc/en/Tutorial/ArduinoToBreadboard
on that page there is a file you can add to the arduino hardware folder so u dont need to use an external oscillator

[reaman4ever]

If I want to program my atmega328 on the arduino and then put it in some circuit without a crystal, can I still do this method and select "ATmega328 on a breadboard (8 MHz internal clock)" ?

thanks

[zgr95]

yes but you have to bootload the chip with that setting

[zgr95]

basically select the board then burn the new bootloader

[kyle brinkerhoff]

how so is the arduino expensive! it comes with its serial converter, breadboard style plugs, replaceable chip, and all the emenitys for the avarege joe to program microcontrollers! plus if you want to go an even cheaper route, alot of companys stores you can actually drive to that sell this chip will often times give it to you for free as a sample!

[janw]

Why isn't it expensive? You can buy cheaper programmers that have serial converters and that are able to progam all atmega and atiny microcontrollers not only the one that fits in the arduino.

Some people use an ardiuno and only use 2 or 3 pins of it. Then you can use an attiny and it will safe a lot of space.

And with a simple breadboard, you don't need those breadboardstype plugs cause most people only use those to link the arduino wit a breadboard. So just plug the microcontroller into the breadboard and program it there.

[kyle brinkerhoff]

the thing is that the arduino is super user friendly because all the guts that are required to make the chip operate correctly are tooken care of, so it throws the user quicker into the programing aspect of mcu applications

[janw]

True, it is an easy start if you want to begin programming. But for me the few capacitors, crystal, button, resistors and serial converter are not worth 30$. You can buy those for less than 10$. And you don't need them to start with programming. All you need is a cheap programmer, a mcu and free software.

I am not against Arduino, I just find it a waste of money.

Still it is cheaper than the basicstamp stuff they sell at parallax.

[zgr95]

i dont wanna be rude but the arduino isnt a microcontroller its a breakout board for the atmega 168/328

[kyle brinkerhoff]

True, but we call it a microcontroller because its just easyer than saying "Breakout board for the atmega 168/328 with built in serial converter that conforms to a unified footprint" its just a whole lot easier

[janw]

Thats the point of the whole discussion!

[jack1197]

awesome it doesnt need an external osilator wow
saves space time and money
and whats that bad about 8 mhz instead of 16 mhz?, not much diference!

[zgr95]

the problem is not the oscillator speed its the fact that the internal oscillator isnt as accurate as an external one

[typomaniac]

i am sorry but i am not sure if i understoof this instructable. Do you say, that i can run the atmega chip without anything around? no resistors, no capacitors, nothing?

thank you very much,

tm

[jackzylkin]

Yup, that's the idea. A 20uF and 10nF cap between bcc and gnd makes the chip more reliable but is not necessary. The external oscillator or resonator is also optional.

[typomaniac]

ok! i'll give it a try : ) thank you very much!

[dustinandrews]

$3? More like $4.40 if you buy in lots of 100. The atmega chip pictured isn't readily available anymore. The ATmega328 with Arduino Bootloader is the recomended replacement and it's $5. ATmega sells some 6 pin programmable chips that are pretty cheap. If I had a project that was simple and didn't need a lot of pins, I would go for one of those. But you might have to buy 1,000+ since the hobbiest sites don't carry them.

[janw]

Use the attiny with 8 pins. Those are available everywhere. I buy my attiny's for about 1.50euro(depending on the type) in my favorite online store.

[dustinandrews]

After some research I found some atmega168p chips for $3.30ea. However, the version of Arduino.exe that I have (which I think is current) won't burn a bootloader because the signature bits are off.

I followed the how to program an AVR with arduino instructable. The wiring diagram was wrong and my chips got real hot (but lived)! I fixed it by using the diagram from arduino.cc.

I had to modify the registry because AVRDUDE wouldn't go to com15. I set it to com4. Turns out there is an easier way: http://createforums.irobot.com/irobotcreate/board/message?board.id=Create_Support&message.id=415

Note: The blank chips come set with the internal oscilator and run at 1mhz.

Then I had some issues with the fuses. Below is the final cmd file that works for me. Sets the fuses, burns the bootloader and locks the flash memory.

Warning 1, once you run the last command, you may not be able to undo what you did without a high voltage programmer. (But if you don't do it, the first program you upload will overwrite the boot loader.)

Warning 2, this assumes you have hooked up a 16mhz oscilator and don't want to use the internal 8mhz (lower power) clock.

ardunioTo168p.cmd
-------------8<------------
@echo off
REM Thanks to http://www.billy.gr/arduino-bootloader/
avrdude -p m168 -c avrisp -b 19200 -P com4
echo enter to continue, CTRL-C to exit. Hit enter if you see 0x1e940b
pause

REM Unlock the bootloader
avrdude -p m168 -c avrisp -b 19200 -P com4 -F -U lock:w:0x3F:m
REM Program the fuses
avrdude -p m168 -c avrisp -b 19200 -P com4 -F -U lfuse:w:0xff:m -U hfuse:w:0xdd:m -U efuse:w:0x00:m
REM upload the bootloader
avrdude -p m168 -c avrisp -b 19200 -P com4 -F -U flash:w:ATmegaBOOT_168_diecimila.hex
REM Lock the bootloader
echo run
echo avrdude -p m168 -c avrisp -b 19200 -P com4 -F -U lock:w:0x0F:m
echo when you are sure you want to lock the bootloader. You might not be able to undo this.

[jackzylkin]

You can get them for less than $3.00. Look here: http://www.mouser.com/ProductDetail/Atmel/ATmega168-20PU/?qs=sGAEpiMZZMvu0Nwh4cA1wUVlLgw9m2DPTt620necFl4%3d

[adamazing]

To address the problem of needing to buy a (more expensive) chip with the 'duino bootloader pre-installed, if you already have an Arduino it's possible to use it to bootstrap a virgin chip: http://www.instructables.com/id/How-to-program-a-AVR-arduino-with-another-arduin/. All your points are perfectly valid of course but I just thought I'd point out that it's possible to save a little off your quoted $5/chip if you already have a working Arduino. $3 does sound a little optimistic, but hey, even if it's $10...it's still less than $30 :)

Great instructable, some others have pointed out, in passing, that this could be done but this should get more traffic and save some more people from spending $30 for every Arduino project they do. :)

[dustinandrews]

You are so right that this is a good instructable. Another slightly less expensive option is an arduino pro min. about $20. I'd like to see someone do a cheaper breakout for that surface mount chip. It love how compact it is. I wonder how much you could shave off the cost if you removed the reset button, LED's and other niceties from the pro mini?

[janw]

Super Instructable!

I never used arduino's for the same reason. I just buy the Atmega or attiny that I like. Some attiny's only cost 1euro so they are very cheap and often more than good enough for what you need.

And I you like to use the arduino as programmer or developmenttool (that's what is made for), thats ok but remove the atmega uC to integrate in you project and reuse the arduinoboard to program another uC.

[hjartland]

Wow! Thank you. I have seen some many projects using this "Arduino" thing. This helps to demystify it and make it seem more doable for the average guy. Watching ST TNG, DS9, and so forth. We are left wishing we could join parts from a phaser to a tricorder to a subspace transmitter. Until the advent of devices such as the Arduino, micro-controllers, USB, and such. We had to either be a board level electronics expert or .. OK we had to be a board level expert. :O Now we are finally reaching the point of interchangeable components. Not much further until we really can join devices and components together in ways we had only dreamed of before! Yeeee Ha! GEEKS! Start you engines .. brains! Lets get to some inventing!

[lordofthedonuts]

*Ceci n'est pas un Microcontrôleur. Yep I know french is hard.

[dagenius]

Yeah I noticed the "s" was missing in pas, and microcontroller just isn't the kind of word that would be spelled the same in french as in english.

[jackzylkin]

http://lmgtfy.com/?q=magritte+pipe

[ckoehler1904]

In step 2, the author is really refering to a famous painting by Dada artist Rene Magritte - http://en.wikipedia.org/wiki/File:MagrittePipe.jpg Very clever!!!

[kyle brinkerhoff]

btw if you own an arduino its super easy to bit bang to the chip

[drhoff]

holy cow! thanks for writing this. i knew you didn't need all the extra goodies of the arduino board to run the chip but i never knew you could run it without an oscillator or crystal. this will save me some money on my next project. thanks!

[ld3300]

thank you for posting this! I have used this same technique on several projects! It is also great for shrinking the project size for small locations!

[rimar2000]

WOW! How I wish to encourage me to learn electronics!