Arduino and NFC

Lokki

Are you able to see a raw output of what is being read through the serial monitor? That would be useful in helping figure out exactly which point you're getting to before it borks itself.

Adafruit has a reasonable tutorial which while being for different gear should be fairly re-usable as communication is via SPI:
http://learn.adafruit.com/adafruit-pn532-rfid-nfc

There's an NTAG203 info dumper here for PN532 boards:
https://gist.github.com/stonehippo/6326056

Lokki

lol, cool. What code are you using to read the tags with?
Also that's a pain - if they're NTAG203 as well, try finding a sweet spot with the ring. You might need to orient it a certain way and possibly slowly move it through the field in order to trigger the read. It may also not be directly on the board, it might be a couple mm above it in a certain area. I encountered this with the iCarte when I pulled it apart (it uses the same kind of pcb antenna) - reading worked best slightly above the board.

itzdarkoutthere

actually, just scanned my other tags with my phone, they are ntag203, same as ring :/ so it would appear it's not a problem with scanning ntag.

that is the tutorial i used when i was getting it setup the first time months ago :P

Lokki

Ah yep, saw that. What are you actually using to read the code after the reader unit though?

itzdarkoutthere

the lib itead supplied
http://imall.iteadstudio.com/im130625002.html

looks like a generic lib from adafruit

// PN532 library by adafruit/ladyada
// MIT license

/* authenticateBlock, readMemoryBlock, writeMemoryBlock contributed  */
/* by Seeed Technology Inc (www&#46;seeedstudio&#46;com)										 */
/* Modified history&#58;                                                 */
/* Nov 5,2012 modified by Frankie&#46;Chu at Seeed&#46;                      */
/*   Add some program comments of some key functions;                */
/*	 Modified the basic interface functions spiwrite() and spiread() */
/*     to be write() and read(),and they will call the functions of  */
/*     class SPIClass but not to simulate timing of SPI;             */
/*	 Rename all of the functions to be like the abAbAb;              */
/*   Modified the constructor of PN532 class;                        */

itzdarkoutthere

@Lokki

Ah yep, saw that. What are you actually using to read the code after the reader unit though?
what do you mean?

just tried the spi lib straight from adafruit's github, same thing. works fine with my other tags but nothing on the ring.
I've put the ring in just about every conceivable position. If there was a sweetspot i feel i would have found it by now.

/e
turned on debugging in the lib, its not picking up anything from the ring, doesn't seem to be an issue with the lib as far as i can tell

Lokki

Ok, maybe I'm looking at the wrong reader unit here - the one I'm seeing is an all-in-one reader which outputs to another device via SPI. That device is an Arduino? I'm wondering what code you're running on that.

itzdarkoutthere

Yah, my pn532 is communicating with my uno via spi. I've just been testing with the example files in the lib rather than my lock code. Same setup as that video I posted, I've just removed the strike from the equation.

I enabled debugging in the lib which was spitting out the unadulterated spi stream. No data while holding the ring in various positions.
Reading: 0x0 0x0 0xFF 0x0 0xFF 0x0

According to the app on my phone (NFC TagInfo) the chip in the tag that works is identical to the chips in the ring aside from the id.

Tom replied to my email and said they would look into getting some inlays sent to me, so hopefully I will be able to test with one of those as well soon.
What NFC modules have you ordered? I will start looking around and order some in the next few days so we cover a larger spectrum in our testing. Will be ordering various antenna's as well, I still have a nagging feeling that is the problem with mine.

/**************************************************************************/
/*!
    @brief  Reads n bytes of data from the PN532 via SPI

    @param  buff      Pointer to the buffer where data will be written
    @param  n         Number of bytes to be read
*/
/**************************************************************************/
void Adafruit_PN532&#58;&#58;readspidata(uint8_t* buff, uint8_t n) {
  digitalWrite(_ss, LOW);
  delay(2);
  spiwrite(PN532_SPI_DATAREAD);

#ifdef PN532DEBUG
  Serial&#46;print(&quot;Reading&#58; &quot;);
#endif
  for (uint8_t i=0; i&lt;n; i++) {
    delay(1);
    buff&#91;i&#93; = spiread();
#ifdef PN532DEBUG
    Serial&#46;print(&quot; 0x&quot;);
    Serial&#46;print(buff&#91;i&#93;, HEX);
#endif
  }

#ifdef PN532DEBUG
  Serial&#46;println();
#endif

  digitalWrite(_ss, HIGH);
}

/**************************************************************************/
/*!
    @brief  Low-level SPI read wrapper

    @returns The 8-bit value that was read from the SPI bus
*/
/**************************************************************************/
uint8_t Adafruit_PN532&#58;&#58;spiread(void) {
  int8_t i, x;
  x = 0;
  digitalWrite(_clk, HIGH);

  for (i=0; i&lt;8; i++) {
    if (digitalRead(_miso)) {
      x |= _BV(i);
    }
    digitalWrite(_clk, LOW);
    digitalWrite(_clk, HIGH);
  }
  return x;
}

Lokki

Ah ok, thanks for that - I'm still waiting for my modules to turn up so that I can form a more knowledgeable opinion on things. Probably should have ordered them earlier!

http://www.ebay.com.au/itm/321097986980
http://www.ebay.com.au/itm/221249331693
http://www.ebay.com.au/itm/161120806341
http://www.ebay.com.au/itm/151217926952
http://www.ebay.com.au/itm/321324810397

A bit of a scattergun approach, but I'll end up using them all I'm sure.

Lokki

Well, I got my small red unit after work today... and it is a pain to get working. The seller provided sketch refuses to compile and the adafruit one isn't set up properly for the unit. Sigh.
So, I'm playing around with getting that one working at all, let alone with the rings.

itzdarkoutthere

@Lokki

Well, I got my small red unit after work today... and it is a pain to get working. The seller provided sketch refuses to compile and the adafruit one isn't set up properly for the unit. Sigh.

Pass along the sketch, I can take a look after work.

Lokki

It's all in here, I'm off to bed!

http://www.elechouse.com/elechouse/images/product/PN532_module_V3/PN532_%20Manual_V3.pdf

itzdarkoutthere

@Lokki

It's all in here, I'm off to bed!

Wow, that lib is all sorts of ugly. Probably better off getting the adafruit lib working.

What is the issue with it?

Lokki

Yeah, you see now why I went to bed hey!
It simply wont verify and compile for me, I was working through it bit by bit and repairing things as I went but I got overtired and ran out of coffee and cigarettes. It was a bad scene.
I'll try again tonight and see how it goes, I'd like to get theirs working at least and then try the Adafruit one after.

Lokki

Sigh. I reckon I've got a dud. The adafruit setup for I2C reports that the PN532 is there, and ready, but the **** thing wont even read the tags that came with it.
Next!

Taylor

I've used my ring successfully with Adafruit PN532 breakout board. They also have a PN532 arduino shield.

itzdarkoutthere

@Taylor

I've used my ring successfully with Adafruit PN532 breakout board. They also have a PN532 arduino shield.

Nice, thanks! How is the performance with the ring?

Taylor

You know, I hadn't really tested that. I'll let you know after I run it through some tests. I [i:12xo79s3]can [/i:12xo79s3]tell you that the sweet spot is right at the 'base' of the antenna i.e. the side of the loop closest to the IC.

Lokki

It's good to know someone is having a bit of luck! I'm stuck waiting on the postman again.

HoodedClaw

My elechouse reader (looks like the same red one Lokki has) came today, and I've just spent a couple of hours trying to get it to work.

Good news is it works with the supplied cards and arduino uno. I used the downloads from here

HTTPS://github.com/elechouse/PN532

Connected to I2C

Literally just got it reading so still need to understand it more but those files are worth a try.

Can't try it with anything else though...