10 Peer-to-Peer Interoperability Results

This section covers the results of the interoperability between the existing TRF7970A peer-to-peer stack and the list of NFC-enabled devices mentioned earlier in the application report (see Table 1). Use the legend shown in Table 6 for the Target results in Table 7 and for the Initiator results in Table 8.

Based on the results of the interoperability tests, TI recommends using passive peer-to-peer modes as they have proven to be more consistent, reliable, and robust than active peer-to-peer modes.

Table 6. Legend for the Result of the NFC Enabled Devices Tests

Legend
	Success
1	The P2P communication only works if the TRF7970A is polling for both NFC-A and NFC-F. The field cannot be disabled between passive commands.
2	The P2P communication only works when the initiator sends a PSL_REQ from 106 to 212 or 424 kbps.
3	Requires both Initiator Active Polling commands for 106 kbps and 212 kbps to work properly.
4	Difficult to establish an active P2P link.
1	The device does not support NFC DEP
NRP	No Reply to Polling command - The target does not reply to the polling command.
NRT	No Reply to Target response - The initiator does not reply to the polling response command.
	Not Applicable

Table 7 includes the interoperability results for test cases where the TRF7970A is a passive and active target. The results show that legacy NFC-enabled devices did not support sending a PSL REQ, instead they would poll for 106 kbps, 212 kbps, and 424 kbps separately. The newer devices go through the anticollision loop and immediately send a PSL_REQ up to 424 kbps for both active and passive communication at 106 kbps or 212 kbps up to 424 kbps. The smartphone devices are listed with model and release date to illustrate that the interoperability across all target modes is better for newer NFC-enabled devices. The TRF7970A peer-to-peer stack is replying to incoming commands SENS_REQ (polling at 106 kbps), and ATR_REQ (active polling at 106 kbps, or 212 kbps, or 424 kbps); however, no further commands are received from the initiator.

Table 7. TRF7970A and Smart Phone Interoperability Results (Target Mode)

Test With Firmware 1.00.35	TRF7970A Modes and Bitrates (kbps)
Smartphone Model (Release Date)	Target (Passive Communication)			Target (Active Communication)			TRF7970A Received PSL REQ
	106	212	424	106	212	424
Samsung Galaxy Nexus (Nov 2011)							No
Blackberry Curve 9360 (August 2011)	NRT						Yes
Samsung Galaxy S3 (T-Mobile) (May 2012)							No
Asus Nexus 7 (July 2012)							No
Samsung Galaxy Note 2 (Sept 2012)							No
AU Arrows Fujitsu FJL21 (Oct 2012)							No
Samsung S3 Mini (October 2012)	NRT			NRT			No
Nokia Lumia 820 (Oct 2012)							No
HP Elite Tablet (Nov 2012)	NRT						No
Samsung Nexus 10 (Nov 2012)							Yes
Google Nexus 4 (Nov 2012)							Yes
Samsung Galaxy S4 T-Mobile (April 2013)							No
Samsung Galaxy S4 (April 2013)							Yes
Hisense Sero 7 Pro (June 2013)							Yes
Asus Nexus 7 (July 2013)	NRT						Yes
Samsung Galaxy Note 3 ( Sept. 2013)	NRT						No
Google Nexus 5 (Oct 2013)							Yes

Table 8 includes the interoperability results for test cases where the TRF7970A is a passive and active initiator. The smartphone devices are listed with model and release date included to illustrate that the interoperability across all initiator modes is better for newer NFC-enabled devices. The TRF7970A peer-to-peer stack does not get a response from the devices that are failing for the SENS_REQ (polling at 106 kbps), and ATR_REQ (active polling at 106 kbps or 212 kbps). The peer-to-peer stack does not support incrementing from 106 kbps → 212 kbps or 424 kbps for both active and passive communication.

Table 8. TRF7970A and Smart Phone Interoperability Results (Initiator Mode)

Test With Firmware 1.00.35	TRF7970A Modes and Bitrates (kbps)
Smartphone Model (Release Date)	Initiator (Passive Communication)			Initiator (Active Communication)
	106	212	424	106	212	424
Samsung Galaxy Nexus (Nov 2011)	1
Blackberry Curve 9360 (August 2011)				NRP	NRP	NRP
Samsung Galaxy S3 (T-Mobile) (May 2012)	NRP	1	1	NRP	NRP	NRP
Asus Nexus 7 (July 2012)	NRP	1	1		2	2
Samsung Galaxy Note 2 (Sept 2012)	NRP	1	1	NRP	NRP	NRP
AU Arrows Fujitsu FJL21 (Oct 2012)		2	2	NRP	NRP	NRP
Samsung S3 Mini (October 2012)	NRP			NRP
Nokia Lumia 820 (Oct 2012)	NRP	1	1		2	2
HP Elite Tablet (Nov 2012)	NRP
Samsung Nexus 10 (Nov 2012)					2	2
Google Nexus 4 (Nov 2012)				NRP	3	3
Samsung Galaxy S4 T-Mobile (April 2013)	NRP			NRP
Samsung Galaxy S4 ATT (April 2013)	NRP			NRP	3	3
Hisense Sero 7 Pro (June 2013)	NRP			4	4	4
Asus Nexus 7 (July 2013)
Samsung Galaxy Note 3 ( Sept. 2013)		2	2	NRP	NRP	NRP
Google Nexus 5 (Oct 2013)

Table 9 shows the results for the time it took to send a 3.6kB file from the TRF7970A to the NFC-enabled devices listed. The NFC-enabled devices were the initiators (passive communication) at 424 kbps. The start edge was measured from the Transmit Complete Interrupt of the LLCP CONNECT PDU (sent from the TRF7970A to the NFC-enabled device). The end edge was measured at the RX Complete interrupt of the SNEP SUCCESS response. The results show that the throughput is highly related to the performance of the processor in the NFC-enabled device. The highest throughput was measured with the Nexus 10, which has the fastest processor.