mini Arduino idea

Vanyamba:
GND pin that is near RST pin. How would you plug this board to a proto-board?

My initial idea was to use this board as a stand-alone with header pins or header female sockets. In other word, this board is not designed for using on a solderless breadboard. However, this board might be used on a breadboard if you have a multi-column breadboard. My board will cover all the holes in a standard single column breadboard which has only 5 holes (0.1" apart) on each side. Anyway, if you have a multi-column bread board and need to use it anyway, here is a way to use the reset and GND pins: attach pin-headers on each side except for the GND pin next to the RST (reset) pin. There is another GND pin (6th from the bottom) on the right hand side of the board for the FTDI connection and you can use it for the reset function.

Where does the 1Mohm resistor go?

You don't need one, that's for building oscillators out of discrete CMOS logic gates where a DC feedback path is needed, the ATmega oscillator circuits are more sophisticated!

frank26080115:
Jeon seems to want to try making a board. Do it right and it'll be worth it. It's great to have a tool tailored to your own needs.

If you want cheap PCBs made, Itead Studio can get you 10 pieces for $28 + shipping, that's way cheaper than anything in North America or BatchPCB.

Graynomad:
I don't see any caps for the crystal, or is that an oscilator?

Judging from his website, he prefers resonators
I think resonators are usually used with a 1 Mohm resistor

Actually, if you make it 5cmx5cm or smaller, you can get it for $12 for 10... according to their website. Have you used them before? Are they actually trustworthy? I've never heard of them, but it is a good deal. The cheapest us provider I've found was sparkfun's side company, which is $10 setup + $2.50 per inch, plus shipping, for 1 prototype. The site you mentioned is $16 including shipping (to middle US) for 10. Definetly a deal if you don't mind waiting the time. (DHL was around $25 for shipping, but they have a basic ground shipping for $4.00, so it's worth the wait for me.) Just wondering about them.

I'd like to try these guys sometimes. Will give them a call eventually and see if they can duplicate a design to cover the whole 10" x10".

Sorry to join the conversation late, but it sounds like you could use the Anarduino: http://www.anatools.com/anarduino-kit/

-- Steven

I used both the 5cm by 5cm and 10cm by 10cm services, I also own a MiniLogic from them, works like a charm! Itead Studio definitely has characteristic products that you won't find else where and his store definitely deserves more attention. There's unique products and cheap graphic LCDs.

SparkFun (aka BatchPCB) is actually slower, because they actually have to fill up a panel with multiple people's designs before sending it to the manufacture in China, where it takes a week to get made. And then it has to ship from China to SparkFun, and then SparkFun to you. The services offered by Seeed Studio and Itead Studio sends your designs right away and the manufacturer is obviously closer to them since they are already in China.

However I do have some criticisms about some of his products (some of which is just personal preference). I don't want to rant too much here about an unrelated topic though.

I do not think it's worth the effort to try squeezing a design into 5cm by 5cm, at least not this type of design. Also Jeon already has an enclosure that he's designing it for.

If you want small, the ATmega328P does not require any external hardware to run at all, just use the internal 8 MHz oscillator. You can literally glue on a button/coin battery to it and have it run code. This is why I think it's pointless to get it that small.

If you are looking for making prototype PCB, you can consider Laen's service:
http://dorkbotpdx.org/wiki/pcb_order

The service has weekly panel already as the response is pretty good. Board is made in US and USD5 per square inch and you'll get 3 copies of the design. Shipment is already included for US!

Before posting, I had already ordered 10 PCBs to Seeedstudio Fusion PCB (http://www.seeedstudio.com/depot/propaganda-pcb-2-layer-10cm10cm-max-p-396.html) for $40+$8 shipping and still waiting for it. They ship from Singapore or Hongkong and delivery takes about 3-4 weeks. Too long! I wonder how fast Laen or Itead studio deliver.

Since the size of my board is small, I could put 5 of them on one PCB. So in total, I will have 50 of them. But they don't allow panelizing, which means I have to cut them by myself. I have no cutter for PCBs, so I'm thinking to make a 'home made' cutter.

Once I receive the PCB and assemble my board, more detail will be posted.

Thanks for all the comments.

Jeon

Panelize the boards yourself and run a series of holes or slots to make the breaking easy.


Rob

Jeonlab:
Before posting, I had already ordered 10 PCBs to Seeedstudio Fusion PCB (http://www.seeedstudio.com/depot/propaganda-pcb-2-layer-10cm10cm-max-p-396.html) for $40+$8 shipping and still waiting for it. They ship from Singapore or Hongkong and delivery takes about 3-4 weeks. Too long! I wonder how fast Laen or Itead studio deliver.

Since the size of my board is small, I could put 5 of them on one PCB. So in total, I will have 50 of them. But they don't allow panelizing, which means I have to cut them by myself. I have no cutter for PCBs, so I'm thinking to make a 'home made' cutter.

Once I receive the PCB and assemble my board, more detail will be posted.

Thanks for all the comments.

Jeon

go buy a mini band saw, and/or mini drill press, both are under $100 most of the time.

I just just use a hacksaw. Clamp the board in place, saw away. Vacuum up the debris and don't blow it around or inhale it.

Thanks for great tips on cutting PCBs, Graynomad, frank and CrossRoads. XD

Hi! I designed Femtoduino: an ultrasmall (20.7x15.2 mm) libre Arduino compatible board .. I don't think you can go really smaller than that!

If you need help or assistance on your project or if you have any questions on Femtoduino, just ask!

Oh.. I also used Dorkbot PDX PCB order, huge thumbs up!

That's tiny, but what constitutes an "Arduino"? Can you just place a bunch of pads around a QFN chip and call it an "Arduino"?

Well, my idea is not to make a tiny or micro scale Arduino compatible board, but to make just small enough to put minimal and through-hole components on it. I have no problem with soldering surface mount components and actually enjoy it, but key points of my design are for more general projects and easy to assemble with minimum number of components at low cost. However, I might also need to be squeezing in SMD parts on the same size board for including FTDI interface and a power regulator for the next version in the near future. :slight_smile:

"That's tiny, but what constitutes an "Arduino"? "
The Arduino is really just the bootloader running on an ATMega chip, yes? Put an LED on D13 and a pullup resistor on the Reset pin, connect VCC-AVCC-AREF to 3.3 or 5V, add 8/16 MHz crystal/caps or resonator, bring out all the I/O pins so the user can connect up ICSP or FTDI to download a bootloader and sketches, and you're pretty much got a ProMini less the regulator.

You can also check out the RBBB. I have a few of their boards. They're small. There's space for voltage regulator and power jack so you have option to power the board with wall adapter or battery. You can also cut off that part to save space if you use battery instead of wall adapter, kind of neat. Just in case you revise your design.

I don't know if your left rows are n*0.1" away from right rows or not or the pins on both rows line up. If you do, you get yourself a good way to plug into a breadboard, prototype, then install in into a small box :slight_smile: Again RBBB can do that.

BTW, I root for DorkbotPDX. I ordered multiple times. They have purple solder mask paint though :open_mouth:
I can also speak some good words for Seeedstudio's board service. I didn't have a problem with my order. The wait was quite long though.

That's tiny, but what constitutes an "Arduino"? Can you just place a bunch of pads around a QFN chip and call it an "Arduino"?

Yes, if you can program it with the Arduino IDE and it can run Arduino code.
Note that I'm calling it an Arduino compatible board. Not an "Arduino".

I use the RBBB alot, but recently saw this on another thread:
http://frank.circleofcurrent.com/usnoobie/

Its similar to RBBB but uses S-USB instead of the ftdi-serial interface.

The problem now in coming up with arduino clones, is that someone probably already did it for you...