ST25R3916B + RFAL does not specify/clear an interrupt after Measure Power Supply command

Forum|Forum|1 year ago
June 28, 2024
2 replies
2423 views

I'm working on porting the RFAL for ST25R3916B to an nRF5340, using the pairing example for X-NUCLEO-8. I have it all compiling and flashing correctly, but things break down during initialization here:

In rfalInitialize() -> st25r3916Initialize(), the issue occurs when trying to measure voltage with st25r3916MeasureVoltage(). After executing st25r3916ExecuteCommandAndGetResult, I get the below SPI trace. The IRQ line goes high as expected, the RFAL then sends a read request for registers 0x1A through 0x1D, and the ST25R3916B does not respond with any active IRQs and does not clear the IRQ line. This results in a memory access violation on the nRF5340.

This is the standard, unmodified RFAL for ST25R3916/B. The DCT interrupt is enabled. The SPI trace looks exactly the same as a previous IRQ read. Is there something different about the Measure Power Supply (0xDF) command? Any help would be appreciated.

ST25 NFC - RFID Readers – ST25R391x Series

This topic has been closed for replies.

Best answer by Brian TIDAL

Hi,

make sure your platformProtectST25RComm/platformUnprotectST25RComm implementation is correct. Basically a SPI ongoing transfert shall not be interrupted by another SPI transfer (e.g. reading the interrupt register). An easy way is to disable the interrupt from the ST25R3916B during a given SPI transfer. On STM32 MCU where the ST25R3916B interrupt line is connected to PA0 GPIO, NVIC_DisableIRQ(EXTI0_IRQn)/NVIC_EnableIRQ(EXTI0_IRQn) is used to temporally suspend and then reenable the interrupt on PA0. A similar mechanism has to be ported to your own MCU.

Rgds

BT

Brian TIDAL

Technical Moderator

Hi,

can you enable the ST25R_SELFTEST switch and provide the Salae raw file?

Many thanks

Rgds

BT

In order to give better visibility on the answered topics, please click on Accept as Solution on the reply which solved your issue or answered your question.

L

LltWcAuthor

Senior

Here's the log file, it looks like the self test completes without any issues.

I hadn't noticed what Ulysses pointed out; no CS transition after the command may very well be the issue. My CS deselect port doesn't fail anywhere else, but I'm going to try a different method just in case.