How can we read/write using SPI

[ANaud.1]

Hi,

I don't really understand the datasheet of the ST25R3916 IC chip.

At page 53, they show an exemple of a direct write command. As I understand, we need to send 1-1-C5-C4-C3-C2-C1-C0. When I check table 13 to see the command code that go for bits C5..C0, the hexa is something like C1 = 11000001. There is 8 bits on the command code and on page 53 they only send 6 bits. I am confused...

Same thing to read a register for example. We need to send 0-1- the register address. There is no register that are 6 bits long, so how can I write my SPI package?

Sorry if it is not clear, english is not my first language and I am still learning SPI communication, so it may seems easy, but I still don't get it ��

Thanks for any clarification.

Antoine

[Ulysses HERNIOSUS]

Hi Antoine,

please consult in ISO/IEC 14443-3 or NFC Forum Digital specs which will describe all the required protocol details.

About 93 20 - first step is check the interrupts, only then read the FIFO. Beware the 9320 needs to be sent using C5h.

Regards, Ulysses