4.2.2 Host Response Retrieval

When clients receive a command, they execute it and generate a response. Since the UART Configuration is an asynchronous, bidirectional, full duplex link, clients can transmit a response back to the host as soon as the response is ready.

The host simply waits for a response to come back from the client after it has sent a command to the client.

Hosts use a time-out to recover from commands or responses that are lost. Hosts can choose whether they want to implement that time-out in the host Firmware Update Protocol Layer or the host Transport Layer. See Host Command Generation and Response Processing for more details.