New! Integrated ATMEGA Arduino Xbee (50% savings)

Where to buy from:

A. Problem Definition

Xbee modules are popular radio modules for ATMEGA based microcontrollers. However there isn't a cheap solution in the market that integrates the two together.

B. The Solution (Yields to over 50% in savings!)

The Single circuit Arduino-Xbee (SCAXb) is a unique and inexpensive solution - in the sense that it is a complete Arduino board at just 3" X 3" with the added functionality of an XBee wireless module being integrated right into the board! What's more, unlike other expensive solutions which exclude the XBee module, the price of this kit at just $35 includes the XBee module too. Designed using the Eagle PCB software, this circuit provides an integrated microcontroller-Xbee interface, optionally extends the 6 analog pins on the typical ATMEGA microcontroller using two 4051 multiplexers and also the output pins using two 74HC595 8-bit serial-in, serial or parallel out shift registers (Perfect for sensors, LEDs, etc for your application)

A transistor is added for wirelessly programming the ATMEGA that momentarily pulls the controller's reset pin to ground. Power supply pins and connections to 4 servo motors are available. A voltage regulator ensures a constant 5V to the circuit. We include the free Schematic and Information Booklet for this circuit with your purchase. This circuit can also be custom-modified according to your needs if you wish to add other features such as FT232 USB to serial communication or special chips that serve the needs of your project. In fact SCAXb Ver. 2 is already under production and includes the FT232 USB connection. Compare this product ($35) with the total cost of spending on an Arduino Board ($29.95) + Xbee Shield (24.95) + Xbee Module ($22) = $76.9.

Visit: for more information

If you switched to SMD, this could be a lot smaller. The multiplexer and shift registers take a lot of space. The price is good though :slight_smile:

This looks great!
I see only one drawback: the arduino shields cannot be used with this board.

Looks really nice. I was wondering when the new version will be available (With FT232 built in).

P.S. Awesome price


Thanks guys for those encouraging responses. We at Myra are working hard to break our own set deadlines and improve the ver. 1 of SCAXb with all the features such as FT232 USB and compatibility with existing XBee shields.

As far as the FT232 is concerned it will be available as soon as the 1st week of June. We have set a deadline of June 3rd when you will be able to buy SCAxb Ver. 2 ($38) directly from our website. June 20th is something that we look to for Ver.3 that would include compatibility with existing XBee shields (42). We see massive cost savings to consumers who are stuck with existing expensive ATmega-XBee solutions.

Karan Kamdar
Myra Robotics

By the way, we did receive a name change request for our product. SCAXb is now Single Circuit ATmega-XBee, renamed from Single Circuit Arduino-XBee.

Check back June 1st week for buying SCAXb ver.2 with FT232 built in.

Very cool. So version 3 will be compatible with Arduino Shields & also have the FT232 built in?


yes that's correct

I think this is a great idea and an even better price. I also think that once it is compatible with other shields or follows a more recognizable form factor, you will start selling these like hotcakes. I would personally like to see one with bottom facing male headers that would be easily breadboardable like some of the arduino variants (iduino, boarduino, ect.)

yes thanks guys again.

There are a lot of ideas that we want to implement. And we do understand the need of the hour. To make it simple and affordable and have all the great features, serving a maximum user base. It takes a lot of effort to get it right and we want to solve this important problem for the good of the arduino community. We are thinking of the SCAXb mini version too where the multiplexers and shift registers are either taken off or SMDed. The point is that there are so many variations possible that we are ourselves a little confused what could be the best selling combination. But we are hard at work. Keep in touch with our development. Ver.2 with FT232 should be out soon.


Yes by the way, if you missed an update on this, we are up with SCAXb KoRe

SCAXb KoRe -

Myra Robotics is excited to announce the new SCAXb KoRe. The new cost-effective integrated ATmega-XBee solution. Features include:

1] FT232 USB, DC power supply support and everything on the regular Arduino
2] Arduino Shield and XBee Shield Support
3] Breadboadable with underside male header pins
4] Integrated XBee module (XBee included)
5] Reset Transistor for wireless code uploading
6] Rock bottom price - Expected retail price $45 + shipping

Myra Robotics has sent KoRe's digital data for manufacturing today. We will get the boards back and assemble them as soon as we can for an estimated release date of June 5th. SCAXb version 1 will still be available.

A few things I don't understand and I would like to ask:

  1. You say "XBee shield support" and also "Integrated XBee module"? Why would you need support for an XBee shield if an XBee is already there?
  2. How well does the XBee work when it is sandwiched between 2 PCBs (the Arduino board and the next shield)? I thought that some "Faraday cage" effect will happen to the wireless communication.
  3. How do you switch Rx/Tx between FTDI and XBee? Using 2 jumpers?
  4. The 5V regulator seems to be placed vertically. This would hamper the use of a full length shield, wouldn't it?

Thank you for the clarifications.

Thanks fluorinc for those questions. We have thought over the issues you addressed before presenting our KoRe version.

The KoRe was really designed to integrate the best features of existing Arduino and XBee solutions that we know exist independently and that eventually lead to a higher price of the end Arduino-Xbee integration.

Now answering your questions in a logical manner:

1] Why would you need support for an XBee shield if an XBee is already there?
As you are aware of, the XBee shield is just another Arduino shield. So support for the XBee shield is assumed. The intention however of explicitly stating Xbee shield support was 2 fold:

a. To give an option to those already having XBee shields to still use the KoRe when purchased without the XBee module (we will be updating our site shortly with the KoRe without XBee version)
b. To give an option to those already having XBee shields to re-use their existing shields in other boards when purchased with the XBee module.

In simple words,

c. If you have an existing XBee shield then buy the KoRe with or without the XBee module [you have a surplus Xbee shield for use in your other boards given the first option].
d. If you do not have an Xbee shield then buy the KoRe with the XBee module which is the cheapest available ATmega-Xbee board currently in the market [applicable to c. (second option)]

The intention is to not replace existing Arduino boards, but if you are buying a new Arduino board, then instead buy the KoRe that has everything you need for ATmega-Xbee integration

2] How well does the XBee work when it is sandwiched between 2 PCBs (the Arduino board and the next shield)?

With KoRe we worked under the assumption that the end user is implementing one shield at a time. For example, with the existing Xbee shield, you are working with just the Xbee shield. In this regard, the KoRe provides Arduino shield support but not with the Xbee on the underside and sandwiched between two shields. With KoRe, if you are concerned about the Faraday cage effect, then remove the Xbee and use the shield that you are working with. If you are not working with a shield on top of the integrated XBee, then you have a cost-effective ATmega-Xbee solution. However, the problem that you addressed will be a very interesting case to solve and we are very much interested to actually see how much of a Faraday cage effect takes place when our boards come back.

  1. How do you switch Rx/Tx between FTDI and XBee? Using 2 jumpers?

Yes that is exactly correct

  1. The 5V regulator seems to be placed vertically. This would hamper the use of a full length shield, wouldn't it?

Not really, because the image shown on the website is not the last updated version. The last updated version that was sent for manufacturing corrected the distance between underside breadboadable pins, re-arranged the XBee position to be at the center and among other things the position of the 5V regulator which is no longer vertical.

Many thanks for those questions.
We hope that we answered them satisfactorily. Do let us know if you have further questions.

Fluorinc this one is for you:

We have updated the website with our last version that was sent to the manufacturer.

Thanks again for your questions

I am not sure you can stack any shield above the board if the XBee module is in place, unless you use taller headers on the base board.

hi nkc,

Thanks for that. You are right in the case that shield stacking on top of normal headers would be a tight situation for the XBee. I believe you carry these headers right? Could you give us a quote on headers and slide switches for 100 of our boards?


I have the long legged headers, but what you need are headers with long bodies and short legs, I recommend using at least double the height of the standard header (body length).

Got you.. Any part number from Digikey, Mouser that you can reference?

As regards to slide switches, do you carry them?

I was wondering if you successfully tested the wireless upload of a sketch, using the XBee.
I noticed that in the previous version you used the schematic described in Rob Faludi's article (even using digital pin 4 to drive the reset pin). I am asking the question because I am not able to reproduce Rob's results. Even manual reset won't allow me to upload a sketch using the XBee (I get communication error in Arduino IDE).
Your comments will be appreciated.