Abstract: A controller and a method for interfacing between a host and storage medium. A storage medium interface includes CH0 circuitry for performing a CH0 process to access a buffer memory on behalf of the storage medium. A host interface includes CH1 circuitry for performing a CH1 process to access the buffer memory on behalf of the host. Access to the buffer memory is arbitrated in sequential tenures to each channel of the multi-channel bus within a maximum arbitration round trip time defined by the time taken by the storage medium to move a distance corresponding to N sectors in which N is greater than one. In the CH0 tenure, the CH0 process transfers data corresponding to N sectors of the storage medium in a multi-sector burst. The length of the tenure of the CH0 channel is pre-designated so that the multi-sector burst is completed within the CH0 tenure.

Abstract: A controller and a method for interfacing with a storage medium. Access to a buffer memory via a multi-channel bus is arbitrated. DWFT (Data Wedge Format Table) entries stored in the buffer memory are read and cached in a DWFT cache memory. Data is transferred to and from the storage medium through a storage medium interface. The storage medium interface accesses the sectors of the storage medium based on their physical locations, as defined by the cached DWFT entries. The multi-channel bus includes a DWFT channel to which DWFT cache circuitry is connected. In a DWFT tenure, the DWFT cache circuitry reads the DWFT entries stored in the buffer memory, and caches the DWFT entries in the DWFT cache memory.

Abstract: An execution queue stores a write command from the host in response to issuance of the write command from the host, and is removed from the execution queue in response to a signal indicating that data designated by the write command has been written to the hard disk. A holding queue stores the write command removed from the execution queue. In response to the command being stored in the holding queue, a request is issued for an acknowledgment from the host. The write command is removed from the holding queue in response to the acknowledgment being received from the host. An outgoing queue stores the write command removed from the holding queue for deletion. The queues are controlled by queue management hardware, the request is issued by the queue management hardware, and the signal and acknowledgment are received by the queue management hardware.