Issue detecting card, ST25R3916B, with RFAL STSW-ST25RFAL002, FreeRTOS Polling

[raj-muniraju]

Hello!

I am working on integrating ST25R3916B into our product based on PSOC 6 CM4.  I can read the ID and initialization seems to succeed but I cannot detect any tags.

Setup:
* I am using STEVAL-ST25R3916B reader expansion board with ST25R3916B.

* I have VBUS connected 5V, 3.3v to 3v3. SPI pins are properly connected and can read the ID. IRQ as +ve edge.

* I have attached spi transaction logs, I have the SPI bus connected to the logic analyzer in case if need any transaction through the logic analyzer.

* I have attached rfal_platform.h and have ST25R_COM_SINGLETXRX enabled and spi_transfer handles the SS pin.

Please let me know anything to try, not sure where to start.

[Ulysses HERNIOSUS]

Hi,

to me it seems the ISR is not handled properly. The software is sending C8 command to turn on the field but ISR is not hitting and no read-out of Interrupt status registers (5A) happens. Then function st25r3916PerformCollisionAvoidance() returns an error and upper layer think field could not get turned on.

I propose to employ ST25R_SELFTEST and see to get basic platform functions operational.

BR, Ulysses

[raj-muniraju]

Hi @Ulysses HERNIOSUS 
Thanks for the quick reply, 
I have enabled the self test and it does fail. Attached the transactions and don't see the interrupt.

I have the GPIO interrupt initialized and enabled for positive edge properly and works if I simulate the GPIO pin. But don't see the interrupt from STEVAL-ST25R3916B reader expansion board.

We have the external pullup on this IRQ GPIO, I have it initialized as pulldown, but goes high as soon as it is connected to ST25R3916B and goes and stays low for the entire initialization.

Do you see any issue with this pullup? What should be the GPIO configuration for this IRQ?

    

[Ulysses HERNIOSUS]

Hi,

having an external pull-up + internal pull-down is for sure not optimal. Also the digital Saleae traces will not show you the truth here. IRQ should only have a pull-down. ST25R3916B will drive it to VDD as long as interrupt condition persists. 

Typically the IRQ pin is only for very short whiles (tens of us) high before the ISR kicks in, reads the interrupt status and thus clears the line again. 

Having long high times on IRQ is an indication of issues - most likely in SW.

BR, Ulysses

[raj-muniraju]

Hi @Ulysses HERNIOSUS 
Thanks. I am able to fix the issue with interrupt detection and processing, now seems to get pass the initialization with selftest but still no card detection.

I am working /ST25NFC_Embedded_Lib_ST25R3916(B)_1.7.0/Projects/STM32L476RG-Nucleo/Applications/Common/Src/demo_edta.c. Can you review the captured spi transactions and give me any pointers?

[Ulysses HERNIOSUS]

Hi,

please feel free to also share directly the Saleae traces, they typically offer a lot more information (timings, IRQ state, etc.).

I the transactions I still find a suspicious sequence:

DSTS    00007809        spi.c                   712     Device: NFC, Tx Data:1681
DSTS    00007809        spi.c                   756     Device: NFC, Rx Data:0078
DSTS    00007810        spi.c                   712     Device: NFC, Tx Data:2300
DSTS    00007810        spi.c                   756     Device: NFC, Rx Data:0078
DSTS    00007811        spi.c                   712     Device: NFC, Tx Data:C6
DSTS    00007811        spi.c                   756     Device: NFC, Rx Data:00
DSTS    00007811        rfal/plf_adaptation.c   118     Timer 2 status 1
DSTS    00007813        rfal/plf_adaptation.c   080     Timer 2 expired
DSTS    00007813        rfal/plf_adaptation.c   082     Timer 2 status 0
DSTS    00007813        spi.c                   712     Device: NFC, Tx Data:1685
DSTS    00007814        spi.c                   756     Device: NFC, Rx Data:0078
DSTS    00007814        rfal/demo_edta.c        276     Demo Cycle 20, state 2
DSTS    00007817        spi.c                   712     Device: NFC, Tx Data:5A00000000
DSTS    00007817        spi.c                   756     Device: NFC, Rx Data:0038200000
DSTS    00007914        rfal/demo_edta.c        276     Demo Cycle 21, state 2

• C6: Send REQA (NFC-A)
• then I presume logging due to txrx timer expired: Should not happen
• 1685: Writing interrupt mask:  setting M_col (and keeping M_rxs, M_rxe M_txe cleared: active)
• And only after that the 5A -> 38200000 (I_txe + I_rxs + I_rxe): This tells something was actually received but due to the previous timeout handling is not retrieved from the FIFO.

So I think still your ISR not correctly operating.

BR, Ulysses

[raj-muniraju]

Hi @Ulysses HERNIOSUS 
Here is the saleae trace, Not able to upload .sal file hope .csv works for you.

Let me know if you find something. I have a worker thread processing the ISR as in /ST25NFC_Embedded_Lib_ST25R3916(B)_1.7.0/Projects/STM32L476RG-Nucleo/Applications/Common/Src/demo_edta.c example.  I picked this as I eventually need to exchange T4 data. Let me know if you have any recommendations of simpler examples I can try if the issue is a delay with isr processing.

[Ulysses HERNIOSUS]

Hi,

csv is not easily readable for me. You can attach .sal when packaged into a .7z or .tar I think.

BR, Ulysses

[raj-muniraju]

HI @Ulysses HERNIOSUS ,

Here is the .sal file. 
BTW, I have to adjust these timeouts for init to succeed.

[raj-muniraju]

And, my SPI runs at 25MHz. I have other peripherals on the bus.