I want to know the answer to the following question:
When are handshake packets generally sent?
All the background I'm provided with is that "Three basic types are ACK, indicating that data was successfully received, NAK, indicating that the data cannot be received and should be retried, and STALL, indicating that the device has an error condition and cannot transfer data until some corrective action (such as device initialization) occurs.". Is that enough to answer the question?
Answer: no