HOST-SIDE CONTROLLER, USB SYSTEM, COMMUNICATION CONTROLLER, METHOD AND SYSTEM FOR PACKET-BASED COMMUNICATION, AND RECORDING MEDIUM

摘要

PROBLEM TO BE SOLVED: To provide a USB system capable of executing SETUP transaction even when a communication path which requires a long time for data transfer is used. SOLUTION: The host SM 32 of a host-side controller 11, when receiving an ACK packet transmitted from a device-side controller 12 to a host 10, stores the packet in a receiving FIFO 26. Then when a SETUP packet and DATA packets are retransmitted from the host 10, the host SM 32 transmits the stored ACK packet to the host 10. Consequently, the SETUP transaction is completed even when communication between the host 10 and a device 13 takes time and the maximum TA time elapses when the host 10 is made to directly receive the ACK packet transmitted from the device-side controller 12. COPYRIGHT: (C)2005,JPO&NCIPI