Patent ID: 8683094

Claim:
A method for a data transmission system having a host, a subsystem and a transmission interface, utilized for the host to transmit and receive a data from a memory of the subsystem via the transmission interface, the method comprising: the host outputting a query command to the subsystem via the transmission interface for querying available memory utilization of the subsystem; the subsystem outputting a return message to the host via the transmission interface for indicating the available memory utilization according to the query command; and controlling data transmission from the host to the subsystem according to the return message; wherein the step of controlling data transmission from the host to the subsystem according to the return message comprises adjusting a size of a data packet transmitted from the host to the subsystem according to the available memory utilization indicated by the return message, wherein the step of the subsystem outputting the return message to the host via the transmission interface according to the query command comprises: generating a sliding window; adjusting a length of the sliding window for recording a storage value of the memory according to each received data and transmitted data; and the subsystem outputting the return message to the host via the transmission interface according to the length of the sliding window.