Change SPI clock polarity between write and read

[blov]

Hi everyone,

I want to access the TI TRF7960 (a 13.56MHz RFID reader/writer) with my Arduino UNO. The TI chip can be accessed with SPI, but with an exotic trick : clock polarity has to change between a write and a read instruction. Below is a drawing from the application report "Using the SPI Interface With TRF7960" (http://www.ti.com/lit/an/sloa140a/sloa140a.pdf).

I'm quite new to Arduino, so I'm not sure if this kind of thing is possible. Does someone have an idea ?

Thank you and best regards.

[pylon]

You can change the SPI mode between the calls to the transfer() method. There's no restriction that this cannot be done at any time. The SPI hardware doesn't know about the CS state.