Hi Benjamin,

Sorry, please note that the forum support of this product has been reduced to first reference our existing documentation and collateral. For support, please take a look to the “Similar Topics” section at the lower right of the thread page. In addition, please consult the existing collateral in the “Technical Documentation” section of the product web page along with the Frequently Asked Question document. Alternatively, you can use the search engine of your choice to look for related E2E threads. With each of these resources we believe it will help with your question.

Hi Charles,

Thank you for this answer, but as far I know: no documentation or subject is relative to this bug with Android devices, neither in Errata, neither FAQ, etc.

Can be interesting to know if TRF7970A isn't compatible with Android devices? Or if a workaround is possible ?

Another question: why this product (marked as 'ACTIVE') is now with reduced support ?

Hi Benjamin,

  Unfortunately, our expert for this device is no longer with us and sorry, I'm unable to provide guidance as to why TRF works with some readers but not some Android devices. 

Hi Charles,

Thank you for quick and honest answer :') - Sad to read !

I replicated the problem outside Android devices - and this Felica polling seems to be problematic to the TRF :(

(top capture was with a SDK where I can insert Felica frame between NFC-A)

Hi Benjamin,

  Although I don't understand how the Felica polling works myself, I find this presentation about Felica support for TRF devices. Hope it is usefully to you. 

/cfs-file/__key/communityserver-discussions-components-files/667/NFC-Forum-Type-3-Tag-Platform-Operations-with-TRF7970A_5F00_10_5F00_08_5F00_2014.pdf

Hi Charles,

Thank you, this is a very interesting document - with nice illustrations - about Felica protocol.

On my side, I perfectly know what data are in the device polling the TRF, on my sample it's : b2 4d 06 00 ff ff 00 03 39 42

Where:

• b2 4d is SYNC
• 06 is LENGTH
• 00 is COMMAND (Polling)
• ff ff is SC (System Code)
• 00 is RC (No request to the card)
• 03 is Time Slot
• 39 42 is CRC

(with a previous preamble)

The problem is that the TRF in emulation mode does not seems to see any traffic (or problem) when a device - here recent Android Pixel - is sending F-frame between A-frames.

Maybe some news on TI's side?

As there is a lots of errata on this chip, limitations and abnormal behaviors... any roadmap for a future one? The TRF7970A is now 13 yr old without any news in the NFC field.

Hi Benjamin,

  For product roadmap, please contact your local TI representative as I cannot discuss this topic on a public forum. 

Hi Charles,

Thank you again to be here with answers :)

I don't think I've a local TI representant as I'm a researcher, but do not hesitate to share contacts !

I'm a little bit surprised, I don't think we discuss about NDA subject here, and I imagine a lots of person would be interested by the answer too...:

• a lots of errata on basic things (emulation/anticol) ;
• maybe a new one with Felica frames in emulation mode (this subject) ;
• and still a lots of question on this forum despite TI wanting to push it in "reduced support".

It can be interesting to have more visibility on the TRF7970A ?

Benjamin DELPY said:

I'm a little bit surprised, I don't think we discuss about NDA subject here, and I imagine a lots of person would be interested by the answer too...:

• a lots of errata on basic things (emulation/anticol) ;
• maybe a new one with Felica frames in emulation mode (this subject) ;
• and still a lots of question on this forum despite TI wanting to push it in "reduced support".

It can be interesting to have more visibility on the TRF7970A ?

Hi Benjamin,

  Sorry for the late reply, I just got back from my travel. 

  I suppose you have gone through the errata at https://www.ti.com/lit/pdf/sloz011. As you have pointed out the device is about 13 years old. There will be no more update to the silicon for fixing any of the mentioned bugs in the document. 

  As mentioned, I don't have good knowledge in how Felica protocol works and therefore, I can't really verify if your reported issue with Felica frame is a hardware issue or not. 

Hello Charles,

Please, don't worry for the delay, this is a forum and we all have hollidays / travels :)

Yep, I've read several time errata, and nothing about emulation. Again, FELICA is not the subject (the device is not supporting FELICA emulation), the subject is how the device is not behaving correctly in 14A emulation, dealing with discovering routinges of some Android devices...