AnsweredAssumed Answered

Can't Detect IRQ Pin Goin' High Level - ST25RU3993

Question asked by Tiago Santos on Apr 19, 2018
Latest reply on May 2, 2018 by Tiago Santos


Just started to test a prototype based in the old FENTO Reader Hardware using the AS3993, now AKA ST25RU3993.

I am able to read/write registers using the SPI pins, but I cannot generate an interruption.


I have been trying to execute the interruption using two methods. First Method:


1 -Write 0x20 to Register 0x35 (Enable FIFO Interrupt)

2 - Write 0x03 to Register 0x3D (Set 48 Bytes for Transmission)

3 - Send the Comand 0x90 (Transmission with CRC)

4 - Write 4 bytes to address 0x3F, 6 times (Supplying less bytes to generate an interrupt)


Pin IRQ stays LOW.


Second one:

1 -Write 0x00 to Register 0x35 (Disable All Interrupts in this Register)

2 - Write 0x40 to Register 0x36 (Enable End of Comand Interruption)

3 - Send the Comand 0x87 (Start AD Conversion)


Pin IRQ stays LOW.

This tests are the same ones used by ST and AMS in their sample codes.


I am sure the MCU pin is working correctly and detecting the rising edge in the correct pin. Tested. I am also sure that the IRQ pin is conected to the correct pin in the MCU.


Has anyone some insights of what could be a possible cause for this problem?