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ST25R3911 gpio interrupt

zhaocz
Associate II



I have integrated the ST25R3911B into a Linux development board, using spi+gpio for communication.

I currently have GPIO configured for edge-triggering (both), and I am polling for card readings at a frequency of 300ms.
However, I've noticed that the GPIO pin used for the ST25R External Interrupt is being pulled high very frequently. causing high CPU usage in my card reading program.

I did not observe the specified trigger condition for the GPIO interrupt in the provided demo. Was it configured for rising, falling, or both edges?

I look forward to your response.

1 REPLY 1
Jasper Preston
ST Employee

Hello,

Could you please provide more details on your environment:
- which version of the demo being used?
- have you been able to run the provided demo, and check the CPU load for comparison?

Could you please capture an SPI trace and either check the content of the interrupt registers, or share it here.

In the demo, the GPIO is configured for interrupt on the rising edge.

Looking forward for your feedback.

Best regards