How to configure ST25R3916 stream mode for custom protocol card emulation

[NV]

The description of the ST25R3916 states "Special stream and transparent modes of the AFE and framing system can be used to implement other custom protocols in reader or card emulation mode." - this makes it sound like it should be possible to implement custom protocols using the stream mode for card emulation.

Unfortunately looking at the datasheet the mode definition register operating modes table only lists stream mode options when the chip is configured as an initiator, there are no stream modes listed when in passive target mode.

Is there a way to leverage stream mode when in card emulation mode, or is transparent mode the only option here (which would seem odd as other posts on the community from ST made it sound like stream mode is preferred over transparent and that transparent mode really only exits for internal testing)?

[Ulysses HERNIOSUS · Accepted solution]

Hi,

stream mode is only available for reader/initiator mode. Its advantage is that all the RF timings will be produced by the ST25R3916. Data goes normally through FIFO.

In contrast in transparent mode the MCU needs to drive signals on MOSI and sample signals on MISO in a timing critical way - typically also synchronous to the RF clock. Typically it requires feeding the MCU_CLK from ST25R3916 back into the clock tree of the MCU. Due to these complications we typically do not recommend using transparent mode.

Best Regards, Ulysses

[NV]

The advantages of stream over transparent are quite apparent timing wise hence wishing to use stream.

Transparent mode being not recommended makes sense when other options exist, but for custom card emulation looks like transparent is the only option.

Thanks for the clarification!