WiSTiCK – Wireless Sensor Networks with Arduino

Following my last post about IoT and WSN networks, i would like to introduce you a new tool for your first open source WSN.
The idea came from where most of my ideas come, a personal need. But i also wanted to make it easily available to all of you so i decided to make it open source and enthusiast friendly.
So, i am proudly introducing The WiStick.
What is WiStick?
The WiStick is a microcontroller board based on ATMEGA32u4, runs at 3.3V and 8MHz.
It has 14 digital input/output pins, 6 analog inputs, a hardware serial port (UART), a USB interface, working independent from the serial port (we use this for programming and debugging purposes), mounting holes for pin headers and screws.
It has a Li-Po JST 2-pin battery connector that you can use to power the board and a very sophisticated charging IC with auto power source selector.
Best of all, we will load it with Arduino bootloader so you can start working with it in a familiar way!
Sophisticated charging circuit
This is a new generation of charging IC’s that is a great choice if you want the battery to work as a backup power source to your system. Let’s say you have an external voltage connected to the board, the charger will disconnect the battery from the main system and charge it.
The board will be powered from the external power source without wasting the battery’s energy and life. That means no charging cycles are spent. If the system need’s instantly more power than the external source can provide it will automatically balance it taking both power from battery and the external source to satisfy the board needs. Also if the external power is cut-off it will automatically switch to battery use.
All these procedures leads to a simple result, to keep the board up and running all the time and extend the battery life and charging cycles to the maximum.
Of course a connection to the battery is not required, we can only work it on external power all the time!
So great!
Wireless Communication Interface
What will be WiStick without the “Wi” thing, right? We want the board to have minimum cost and maximum functionality, so we have chosen the most popular, available, low cost and trusty RF module existing today. This is the Nordic nRF24L01+ !
Yeap, you have seen it around and yes it’s as good as they say!
Now you may ask, why it is not integrated on the board but we are using a nasty header instead?
Well i can give you two good reasons; firstly, the cost of a small RF module based on nRF24L01+ shipped from China is unbeatable! The Mouser, a major distributor in EU, have these for 3 euros each, without calculating the cost for RF antenna and RF optimization.
Secondly, we want to make this board as modular as possible, so if in the future there is a better RF module or if you want to choose between a low cost PCB antenna module or a long-range high power with external SMA connector, you can have this extensibility easily.
When it will become available?
In the following days the first PCB’s will arrive and we will start the first tests.
If everything goes well we will start the production of the first batch and at the same time the developing of the open source firmware!
What I would love to see is your comments and your ideas on this. The more we feel that you like it, the merrier the time that will be devoted on this project.
So, stay tuned, we’ve got more fascinating things coming soon!
Let me know when these go live – I have an application for them… (if the cost is low enough
Hi Richard,
thanks for your interest.. i have some engineering samples in my hands right now. They are in a test phase, if they pass it with success the first batch will go for production.
Watch for status updates on our website.
Regards,
Kostas
Seems you could reach a sweet spot there in terms of price. I’m a bit concerned about the reach using 2.4GHz radio though (as compared with 868 MHz solutions).
Did you publish your schematic ? Is there a LED on D13 for example ? The nRF module is SPI, right ? So no remote programming possible ? Any library to be published ?
BTW, if going with Nordic, what do you think about using directly the new nRF51822 chip that can do both BlueTooth and Nordic’s proprietary ? It has a cortex M0 core, much more powerful than ATmega ! Barely bigger at 6x6mm 48-pin QFN… and probably barely more expensive. But of course Arduino compatibility is more problematic…
Dear Chris,
i have tested the RF Modules with the PCB Antenna indoor and it can communicate through concrete walls 2 rooms further, thats about 15 meters with 2 walls between… BUT… the beauty of this is that using a special firmware you can create a mesh network. So it’s device can work as a repeater, so if you plan to have some devices around your home you will not have any problems with range.
The RF Module is SPI but the beauty of this board is that you have also a hardware serial port available so you can use any other rf modules you want. The RF Header just expose the SPI pins and it’s ready for nrf24l01 modules available.
Also there is a high power nrf24l0a module availale with external antenna that can reach more than 1KM range outdoor. I will test one of these someday.
Soon i will post the schematics too for this board, there are 2 leds that are used by Arduino bootloader for RX -TX indication and you can use them also from your sketch.
The battery charger is impressive, i will make a post about that later.
Regards,
Kostas
Dear Kostas, This module, especially the charger IC and the nRF mesh possibility, sounds fantastic. Any update on this? Maybe a Kickstarter or Tindie? You have a pledge guaranteed from me.
Cheers,
Anders
Where do I buy these things? I’ll keep looking… I have applications in mind for a couple of your products.
Hello,
we are now testing this board and making some minor changes to the PCB. It will be the next project that will go to production, i estimate to be ready to sell in 3-4 weeks.
Thank you for your interest!
Hi,
can you describe in details why I have to choose your solution instead of one with 802.15.4 standard?
I think that Arduino and bitrate of your solution are two nice advantages. Is there something more?
nrf24l0a vs nrf24l0+ is negligible, for .79c per unit (nrf24l0+).
I have found it very difficult to get these units running Starburst / Multiceiver (due to my inexperience) @ 250kbps with packet anti-collision, but 800mtr is possible L.O.S.
Please let us know what’s going on!
Awesome. I have been working on wireless sensor nodes for a while now.
Been doing eagle pcb:s and done a lot of thinking, but now I have to buy these instead. Any update on when they may be available?
Regards
Hi Carl,
this project is still in testing phase… we will make slightly improvements before going to production. I will let you know when there is a status update on this.
When???
When will this be ready? or can you at least tell us a cost? Thank you. Im working on a mesh sensor network now using the nrf24′s and if the cost is right Ill be making a big order with you. Thanks
bump.
This is great information, thanks’ for share!
Kalimera Kostas
Did u get any progress on this?
Hello,
the project is finished last year. The problem is i can’t find the funding to go to production. The profit margin for a viable market price is very low for this project.
A similar project with RFM12B modules is http://lowpowerlab.com/moteino/
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