72.6.4 USB V2.0 High Speed BUS Transactions

Each transfer results in one or more transactions over the USB bus.

Five types of transaction flow across the bus in packets:

  1. Setup Transaction
  2. Data IN Transaction
  3. Data OUT Transaction
  4. Status IN Transaction
  5. Status OUT Transaction

A status IN or OUT transaction is identical to a data IN or OUT transaction.

Figure 72-2. Control Read and Write Sequences