Using PN7160 only through I²C pinout.

[Jansch]

For our product we only have 2 free pins we could use for the PN7160 NFC board. One SDA and one SCL. As a proof of concept I am trying to run the polling example (nfcDemoApp poll) with the eval kit only connected through I²C (aswell as power). Is there a possibility to do so? I have so far tested it with and without the interface board without success. I just need to proof that I don't need the Interrupt pin, which in my knowledge I shouldn't need when polling. Advice would be greatly appreciated!

Also furthermore the starter guide is not 100% correct, the example doesn't work on Raspberry Pi 5 with Bookworm installed.

[Daniel_Gutierrez]

Hello @Jansch, Good Day!

Thank you very much for your interest in our products.

It is important to mention that some of the steps for software setup described in PN7160 evaluation kit quick start guide are meant to be executed only on the OM27160A1HN version of the board and some of them are meant for the OM27160B1HN version. Please make sure you are working with the OM27160A1EVK board, as this is the one that embeds the I²C variant of the PN7160.

I would like to ask if you could please provide more details about the names of the power pins that you are using, as well as if the GND pin is being connected? 

Keep in mind that in all cases the VEN reset pin, should be handled in order to make host communication possible. Also consider that pins such as DWL_REQ, which provides the possibility for firmware upgrades, and IRQ are equally as important in order to ensure data flow control between PN7160 and the host.

Please refer to section 11.5 of the PN7160/PN7161 Data Sheet to get a deeper understanding on how to handle those pins for the overall wellbeing of the system.

My best regards,
Daniel.

[Jansch]

Hey Daniel,

I was curious, do I have to set the pin actively to different states, or could I just put a set pullUp onto it?

[Daniel_Gutierrez · Accepted solution]

Hello @Jansch, Good Day!

Please consider that our recommendation is to follow the guidelines for the handling of those pins described in the referred document, given that with any other way of handling we cannot ensure a proper functionality of the device.

However, if you do not require to download upgrades for the EEPROM of the PN7160, you could consider not handling the DWL_REQ pin and just have it connected to GND, given that this pin is only used when such an upgrade will take place. Please refer to section 11.5.4 of the PN7160/PN7161 Data Sheet.

On the other hand, dynamic handling of the VEN reset pin is recommended, since in possible power-up sequences, it needs to be LOW for at least 10 μs before pulling up and starting the boot process to make host communication possible (see Table 36 in the same document).

Please make sure that any test you make, you do it based on the documentation we have provided. You may refer to the sections mentioned above and Figures 20 to 25 to get a deeper understanding of the possible power-up sequences.

My best regards,
Daniel.

[Jansch]

Hello Daniel,

I am asking because we have a size constraint board and nfc is an optional requirement, therefore we are trying to get it to work on our board without it being absolutely necessary.

The only way we could make this happen is, if we could use the PN7160 through I²C pins alone, meaning:

1) GND

2) Power

3) SDA

4) SCL

You mentioned I need to have the VEN pin connected. Therefore we sadly won't be able to work with NFC here. 

I do own the correct board. Through further research it seems like the Pi5 problem is a common one, and not yet fixed on NXP side. I found multiple posts in this forum suggesting so.

Either way I hope you have a great day!