Patent ID: 7640366

Claim:
A storage controller comprising: a plurality of storage devices, each storage device having a storage medium, data stored in the storage medium being capable of accessing by a host device; a plurality of access control devices operatively provided for respective ones of the plurality of storage devices individually, each access control device functioning (1) to control data accesses to a storage device by control step units, each control step unit sequentially executing a primary control command analyzing step for receiving from the host device and analyzing a primary control command specifying content of the data access, a data access step for performing a data access with the storage device corresponding to the analyzed content of the primary control command, and a status transmitting step for transmitting to the host device a status indicating results of the data access, and (2) to queue execution of a control step unit for a chronologically succeeding data access while a control step unit for a preceding data access is being executed until execution of a current control step unit has completed; and a serial communication unit that performs access-related data transfers between the host device and the access control device specified by the host device in order to execute the control step units, the access-related data including at least the primary control command and the status as transfer elements, using serial communications according to a format of polling the plurality of access control devices, and that performs a process to transfer a set of transfer elements including the access-related data for control step units targeting different access control devices according to a format that allows the transfer elements in the set to be mixed chronologically.