pub const WAKE_DELAY_US: u32 = 4_500;Expand description
Time to wait after the wake pulse before the first I2C transaction.
The datasheet specifies two relevant timings here:
tWHI: 1500 us minimum, the legacy I2C-bus-recovery delay,tHTSU: 4100 us maximum, the host-to-target setup time before the chip will ACK its address.
CryptoAuthLib historically uses 1500 us and it works on most chip
revisions, but some 608B silicon needs the full tHTSU window. We
pick 4500 us as a single delay that covers both with margin. The
extra ~3 ms over the strict tWHI is invisible to the user (PIN
operations take tens of ms anyway) and removes a class of “first
transaction NACKs” bring-up bugs.