Can you suggest any particular chip which is cheap and have the smallest amount external parts. I am considering between NXP PN532 and AS3909/AS3910 but maybe you have better option...
Hi Bartek, I'm pure SW developer and my knowledge of HW design is limited so I cannot judge these items from layout/PCB real estate/BOM cost point of view. I'd expect that for reader this isn't such a problem because HF (13.56MHz) contactless (NFC if you want) is such specific discipline that you need real expert to produce at least so-so tuning and then you simply take his recommendation (because saving few cents on BOM or similar is not worth months of learning and discovering completely new vendor/component). At least this is what I've seen during my professional career in smart card business;)
I have made a device with both nRF52 and PN532 on the same board. I expect to start a Kickstarter campaign soon. You can find a picture here:devzone.nordicsemi.com/.../
Please let me know of you are still interested, or if you found your solution already.
Hi Cristian, the board looks nice and clean, nice job! I'm wondering if I2C provides enough bandwidth in case you need to do some roundtrips between BLE MCU and PN532, solutions I know usually use faster SPI at 4 or 8 MHz. Also using nRF52840 might be useful because of larger buffer sizes SPIM (TWIM seems to be stuck at 8 bits = 255B which might be limiting in some cases, but I haven't studied PN532 wired protocols in detail). But as far as I know there is no "open hardware BLE equipped NFC reader" so it looks useful! I hope you get funded with your project. Cheers Jan
Dear Jan, Thank you very much for your reply. Apologies for the delay. Yes, I2C is not the best, but it permits me to run nfc_tag_reader example with just a few modifications. I have not had the occasion to test it yet, but I ran another example with the board and it worked. I think your suggestion is great and I will try to include SPI in the next revision (or both). My main goal now is to include other tags for reading and writing, for which I have to write the libraries. Thank you for your wishes and I wish you a very good 2017!
