TRF7970A: Basic NFC Read/Write help

I've attempted to connect to my phone via P2P but even when P2P is started and RW is stopped it still attempts to connect via RW. The blue light will turn on indicating RW mode is on, and it will switch to the RW screen but immediately go back to the NFC Config. screen because RW is stopped (This happens in a continuous loop in these conditions). Is there any way to make the TRF7970A recognize a smartphone in P2P mode? That would be the overall goal anyway but for now I was hoping to get at least a one-way form of communication.

Thanks

Hi Andrew,

 In the NFCLink Standalone Getting Started Guide, it has below note about NFC communication with Android phones for read/write. 

 For P2P operation, can you try the standalone P2P firmware provided in this app note? In section 10, it also talks about Peer-to-Peer Interoperability between TRF7970A and some smart devices. The app note was published a few years back. The test results may or may not be still valid for smartphones as of today. In the meantime, I will consult with some experts. 

https://www.ti.com/lit/pdf/sloa192

Charles,

I've attempted to utilize a number of different apps through my smartphone as well as attempted using an Advantech tablet with windows software to try interfacing. This was met with little return, unfortunately. As the smartphones seem to default to read write mode even when its off, the tablet seemed to do the same with P2P mode. However, I was not getting any error messages when sending to the tablet in P2P mode, although there were no messages delivered to the tablet. Please get back to me as soon as possible with any information that might allow for simple communication between the TRF7970A and a smart device like a cellphone. 

Many thanks,

Andrew

Hi Andrew,

  I will need to consult with our expert and get back. 

Looking forward to it.

Thanks again,

Andrew

Hi Andrew,

  I must admit I'm not an expert in this subject and I'm learning as I speak. While I'm reaching out to our prior expert I have searched e2e archive and have some feedback.

 - Have you had a chance to try the software collateral in the NFC active and passive peer-to-peer communication app note and also go through the app note?

 - Is your phone app enabled and capable to send NDEF message format?  I suppose so, correct?

  - I also suppose your phone is enabled and support for Peer-to-Peer transfer, correct?

  - My understanding is that Passive P2P has been significantly more consistent than Active P2P. Can you confirm that your smart device is in passive mode?  The firmware will poll for Passive P2P first. If an NFC device operating in peer to peer is in passive mode, only another passive device can communicate with it. An active device will not be able to communicate with a passive device even if it has a proper initiator/target relationship.

  - The firmware example shows basic functionality of the stack but further development is to be handled by customers if you are going to send large size of messages. Of course at this stage, the size is not an issue but rather a basic connection in P2P has yet to establish on your setup. This is just to give you a heads-up down the road. Having said that, all the hooks should be in place to support more.

Yes, I've been going through the app note documentation and I've been utilizing both the RW and P2P code via Code Composer Studio as recommended via the Quick Start Guide for the TRF7970A. 

Yes, per my research it appears all current android devices are NDEF capable, although I can't seem to find any way of checking that for my personal device directly. I've been operating under the assumption that they are NDEF and P2P capable as my phone can RW with RFID tags and can successfully utilize tap payment applications which are the most common form of P2P. 

I plan on pursuing larger data transfers in later stages, but not in the current scope. I want a proof of concept at the current stage so small text files, or a URL would be sufficient.

Is there any reason to believe that the NFC TI Tool Version 1.8 would have issues transferring data between devices? The TRF7970A is definitely recognizing the smartphone as the Com Log is returning: "T4T Tag Detected......Tag UID: 0x08CB07DB". So, there is successful device recognition, but there seems to be an issue on the software or firmware level preventing communication between devices. The RW error "T4T Write Fail: NDEF message size not supported by tag." tells me that either the message is too large to send or too large to be received by my phone (I'm sending messages in the 2–5-byte range currently, so very small) I'm not sure if there is an inconsistency with data translation or something else entirely but this is what I'm currently working with.

Thank you for your assistance I look forward to finding a solution,

Andrew

Hi Andrew,

  I tried two sets of DLP-TRF7970ABP+MSP-EXP430F5529LP running the same firmware (the NFCLink Standalone GUI and example code from http://www.ti.com/lit/zip/sloa227.). Both peers could send messages to each other. Please take a look at my test below. 

I have the two DLP-TRF7970ABP+MSP-EXP430F5529LP stacked as shown below for best antenna reception. 

I'm not sure about the mobile phone setup. Doing some research, there used to be Android Beam that allows for P2P communication but that is deprecated after Android 10. I think it is replaced by Near-by-Share. My understanding about Near-by-Share is mainly for two Android devices to share media such as photos and etc. I'm not sure you can do P2P between a Android phone and a TRF7970A configured for P2P mode. Is it possible that Android phone would not talk to a non-Android device? I don't have the knowledge on the Android OS to answer this question. 

Which app on your phone are you using for P2P? I cannot find a app from the Play Store that supports NFC P2P. I can only find reader/writer apps.  As far as the firmware goes, it is working for P2P mode. 

I was able to replicate the experiment of using two pairs of devices in P2P mode. This is useful but not quite what I need, unfortunately. I did verify the information on android devices, you are correct, I did not realize there was a switch.

I also have a Windows operated tablet that seems to connect to the TRF7970A in P2P in a similar manner as the Phone did in RW where the Com Log will show it recognizing the device. The only problem is that I can't seem to find a P2P app that will allow the two devices to interface. When I send a message from the TRF7970A to the tablet there is no message that seems to be sent or received. 

Would you have any information on any apps for P2P that can be downloaded onto a windows device to interface with the TRF7970A?

Hi Andrew,

 Sorry, I have done some search but to no avail on apps for windows tablets.