Best posts made by MrStein

Hi, today I received my Nfc arduino board from china.
Here are the first picture and caracteristics:

-> Atmega 328
-> pn532 connected by uart
-> antenna designed for the NFC ring (but it's need some modifictions for the according circuit)
-> FT232 (USB to UART)
The other caracteristics are the same than the arduino uno (3v3/5 v output,... SPI, I²C, UART)

Reading;
-3cm for normal card tag
-2cm for badge tag
-1cm for the nfc ring....

I thing the according circuit isn't as good as the simulation so I expect a bigger reading distance with the version 2. But with this configuration it's still better than the PN532 shield with my NFC rings (normal ring) :)

The version 2 (WIP) will have:
-> uhl connector for a deporting antenna
-> Bluetooth loow energy module
-> MSP430 proc (not sure)

What do you thing about that? :)

D-1 ! :)

After 1 year, the keyduino nano is available! :D
You can found the board at elecrow for 25$ (here)

It's still a ATMEGA32u4 but I redesign the NFC antenna and add few ameliorations.
Currenlty I try some project like communication with a credit card, HCE communication, etc. If you have any cool projet to suggest with or without the NFC ring, tell me !

Some news!
Today I start working with a friend on the according circuit,

(beautiful no?)

That improve the reading distance of the big tag (badge -> 3cm now) but the reading distance of the ring is still 1cm...

I will work more on the antenna design, and I expect found something.

First picture from china:

Normal one:

As you can see, there are 2 buzzer pad in more for identification application :)
Nano one:

I really like the black PCB with white silkscreen :D
For the nano one, the connector is maybe a little bit too big, btw it will be a male connector instead of a female one.

Hi, thank you for the support :)
The KeyDuino normal will be a KickStarter soon (in november normaly)

Here is a tutorial that allow you to control your car doors by a NFC communication;

code here : http://keyduino.forumsactifs.com/t24-nfc-doors-unlock
Lib and APK here: https://github.com/CITCEuraRFID/KeyDuino
NFC ring code : KeyDuino lib>example>relay shield

Hi,
The actual design antenna of the current shield are not well designed for the small tags like badge and nfc ring, but the pn532 shield is one of the less worst for the NFC ring. (TRF7970A work too).
But the inductive field is not enough for have a good reading distance...

Actually, I work on a arduino NFC & arduino nano NFC with a antenna / according circuit designed for the nfc ring. With the test with a RC522 reader I can read to ~2cm. Now I wait the current board with a PN532 from china for some test. After that I would like to make a Kickstarter with all schematics in open source (antenna design too), but it's not sure yet. Maybe you can be interested by this issue?

New eagle project:

A PN532 chip with the resonnant circuit (a friend working on a more suitable antenna for the NFC ring). Connexion by SPI.

******link for the pn532 ******

this is for a project of a radio frequency switch with nfc control.. I have not yet the implenter technology for the PN532 (0.2mm space between pins). So I'll see if the mechanical engraver can achieve the board or if I should use a QFN32 adapter -> DIP 32

I also working on a simular project using a chip TRF but it is related to my job and I can not disseminate plans ... sorry!

So I make the board with EAGLE and there are made in china, with MAKERSTUDIO (low cost: 10boards for 10$. and assembling the components is not expensive ;) ).

Oh, I forgot to say but I also have a arduino nano version in progress :)

Work in progress for the version 2. I use 1 atmega 328 connected to the pn532 by SPI for the reading and a atmega32u4 (leonardo) for the programmable chip. Nano version will be difficult in 2 sides pcb...

I also put some headers on the i2C communication for add a Bluetooth low energy module (maybe I will add a NRF chip for an other board but I don't add the time for make and test a 2.4Ghz antenna yet.

oh, I make a prototype of an arduino nano bluetooth (not tested yet), if you are interrested, here are the files;
http://www.partage-facile.com/TL9CEJT1GP/arduino_bluetooth.rar.html (click on "téléchargement régulier")

I was wondering why the pn532 from electrohouse and my first version became hot with the time. It's because there is not level converter (5v to 3.3v for the spi/i²C/HSU communication. That rectified in the version 2.

I also add a switch on an interrupt pin and a RGB led for select the communication mode (BLE mode, NFC mode, BOTH or nothing).

If you have any question / idea of application say that to me !
Ah, and "NFCDUINO" name is already take, someone have a idea? :D

Keyduino will be assembling soon, first test on december :)

3d view from sketchup:

here is the board finished:

Black jumper is for simulate the brake
blue&brown are supply
brown, blue & yellow/green are contact & starter.
I also make some videos for show how plug this device & how supply, bypass the immo,... (in french)
https://www.youtube.com/playlist?list=PLBiQyVl185A4OzemFMIH5aewKNF8k3Xg1
Part1: neiman connection
Part2: supply
Part3: bypass immo
Part4: the board explication & conception

Next video will be the brake connexion & global connection

You just solder the antenna where was the previous one? does the according circuit resized?
I have order the antenna with the hole and I think it can provide good result with a recalibration.

I will make soon the conception of 6 differents antenna like the first one I have done, I expect have great result and provide all the design on eagle :)

After some long days of eagle conception, 3th version is done !
What is new?

-> physical USB for the keyduino nano (stronger).
-> only one atmega 32u4 for the classic version (previously a atmega32u4 + a atmega328) that's really cheapper.
-> re-design of the board, silkscreen of the nano one was unclear.

And, last new, I bought an old oscilloscope for modify the nfc antenna!

and after a lot of antenna design and according circuit calculation:

-> better antenna and according circuit, that improve the reading distance of a badge by 1cm and of the nfc ring by 0.5cm (usefull if you use a box between the antenna ant the nfc ring) :)

I start a conception of 6 prototypes (3 nanos and 3 classics) now the only thing I can do is waiting and search for small batch production in china :)

Sorry, the video was updated, here is the available one ;)

Your project but with a KeyDuino :)

@LoganFive No problem for question :)
You can use the board directly with a OTG cable yes. For exemple, I run LIBNFC on a KALI with my galaxy s4 (emulated) and all is okay.

The board will be in crowndfunding in november !

Tomorrow :)

The KS link
https://www.kickstarter.com/projects/1535978353/keyduino