In spi_comm_slave demo, as I see, after receive request from client, the broadcom kit will send data via SPI
result = application_spiffy2_send_bytes(attrPtr, len);
But SPIFFY2_MAX_NUMBER_OF_BYTES_PER_TRANSACTION is only 15, that mean we only send maximum 15bytes at same time.
How do we send a larger amounts of data ( > 15bytes )?
As you saw, spi_comm_slave sample has 15 bytes x 16 buffers at application level.
Buffered data will be transmitted after the interrupt.
We can transmit up to 16 bytes data at the same time. (it has only 16 bytes buffer.)