From Datasheet (Reference)
Software Setup
Scope Data @ 2MHz (ACK - START)
Using Oscilloscope
Using Logic Analyser
Latch at 3.5clk, data ACK at 4th Clock
Scope Data @ 8MHz (ACK - START)
CLK to SPI Start Delfino Reaction Time
2MHz Test
8MHz Test
At 8MHz test, the GPIO react later than SPI transfer start
A 3us delay for software to react to the clock
Message Rate
2MHz Test
40us per message → 25kHz
8MHz Test
25us per message → 40kHz
SPI Clock Rest Time
2MHz Test
8MHz Test