What I see is that the NINA_ACK pin is high until Nina is reset, then it stays low.
Then, before sending any command, the library does this:
WAIT_FOR_SLAVE_SELECT()
SpiDrv::waitForSlaveReady();
SpiDrv::spiSlaveSelect();
which boils down to:
- wait for NINA_ACK to be low (OK)
- set SPI CS to low (OK)
- wait for NINA_ACK to be high (NOK)
Basically, setting the Chip Select pin to low does not make NINA_ACK to become high. What can it mean?