Abstract: Briefly, in accordance with one embodiment, for example, USB display device operation is disclosed in absence of a local frame buffer.

Abstract: Systems and methods schedule periodic and non-periodic transactions in a multi-speed bus environment that includes in a downstream hub a data forwarding component, such as a USB transaction translator, which accommodates communication speed shifts at the hub. The method may comprise receiving a split packet request defining a transaction with a device, tagging the request with an identifier allocated to the data forwarding component, storing the request in a transaction list associated with the identifier, initiating transfer of payload data, and updating a counter associated with the identifier to reflect an amount of payload data for which transfer was initiated. The identifier may have associated therewith a counter for tracking a number of bytes-in-progress to the data forwarding component and one or more transaction lists configured to store a plurality of split packet requests awaiting execution and state information regarding an execution status of the requests.

Abstract: Systems and methods schedule periodic and non-periodic transactions in a multi-port bus environment. The method may comprise performing multiple search passes through a first array of endpoints to determine whether dispatch resources are available for active endpoints satisfying a set of sort criteria. When dispatch resources are not available for an endpoint, a sort level may be marked with a marker to indicate that an endpoint has not been serviced. After the active endpoints in the first array have been serviced by dispatching a periodic transaction to the endpoint or by marking a sort level corresponding to the endpoint, a non-periodic transaction may be dispatched to an active endpoint in a second array. In response to receiving an indication that the dispatch resources have become available, a subsequent search pass may be made through the first array, starting with a highest priority sort level that is marked with the marker.

Abstract: A host controller for a bus is disclosed. The host controller includes a plurality of functional modules interconnected to manage transfer of data between a host bus and a root hub configured to communicate with one or more USB device endpoints on the bus. The plurality of functional modules comprises a DMA engine to transfer one or more data payloads between the host bus and the root hub, a transfer manager configured to determine what control data and/or data payloads should be transferred, and a scheduler to schedule actions performed by the transfer manager. A plurality of control memories, each associated with one or more of the functional modules, store state and/or data information fields accessible by its one or more associated functional modules. The plurality of control memories are distinct and independently accessible from one another.

Abstract: Systems and methods schedule periodic and non-periodic transactions in a multi-speed bus environment that includes in a downstream hub a data forwarding component, such as a USB transaction translator, which accommodates communication speed shifts at the hub. The method may comprise receiving a split packet request defining a transaction with a device, tagging the request with an identifier allocated to the data forwarding component, storing the request in a transaction list associated with the identifier, initiating transfer of payload data, and updating a counter associated with the identifier to reflect an amount of payload data for which transfer was initiated. The identifier may have associated therewith a counter for tracking a number of bytes-in-progress to the data forwarding component and one or more transaction lists configured to store a plurality of split packet requests awaiting execution and state information regarding an execution status of the requests.

Abstract: Systems and methods are provided to track the state of a data forwarding component, such as a USB transaction translator, included in a downstream hub within a multi-speed bus environment. The data forwarding component accommodates communication speed shifts at the hub. The method may comprise receiving a split packet request defining a transaction, performing a lookup in an associative array using hub-specific information provided in the split packet request to determine whether an identifier is allocated to the data forwarding component, and if it is determined, based on the lookup, that an identifier is allocated to the data forwarding component, storing state information associated with the split packet request. The associative array may include multiple identifiers, each of which has an associated state field configured to track information, such as the number of packets-in-progress and bytes-in-progress to a particular data forwarding component.