Seeedstudio NFC Shield v2.0 I2C

Question

I am using NFC shield v2.0 and it seems Sel0 and Sel1 pins are set for SPI mode and we cant change it (saw in schematic files). So is there any way to change the values on this pins via software(program) to make it to work for I2C mode?

and inDataExchange function is not a member of SPI.cpp library while it is in I2C.cpp library? is there any way to make HCE work with SPI mode?

Answer 1

The supported modes of the PN532 chip on the NFC Shield do not depend on the interface used for communication (at least when it comes to NFC operating modes). So you should be able to send whatever commands you want over the SPI interface just as you would with the I2C interface.

With regard to the inDataExchange command, this command seems to be implemented in the current version of the library (see the github repo).

And no, besides wiring the interface selection pins to a different value, there is no other way to change the interface mode at runtime.