SOF interrupts in the CY7C64613 (FX)

Question: When will the SIE generate an SOF interrupt?

 

Answer:

In the EZ-USB Technical Reference Manual on page 7-22 at the bottom of the page, labeled "About USB Frames", it will confirm the answer. The SIE will generate an SOF interrupt if it detects a missing SOF packet. This is to keep ISO transfers in sync with scheduled timing.