摘要:
An image forming apparatus receives raster image data transferred from an external device and forms an image on the basis of the received raster image data. The apparatus includes a processor that controls a transfer of the raster image data from the external device, a first memory connected to the processor through a first bus is used as a working area of the processor, a second memory that stores the raster image data, a memory control unit connected to the second memory through a second bus controls an operation of writing and reading the raster image data in and from the second memory, a printer engine that forms an image on the basis of the raster image data, and an engine control unit that reads the raster image data from the second memory through the memory control unit and supplies the printer engine with the read raster image data.
摘要:
An information processing system includes a high-speed serial bus that transmits and receives data independently over communication channels via a tree-structured network including a point-to-point connection, and a control unit that issues a request command based on a request synchronization signal for data with a timing constraint on line synchronous transfer by a line synchronization signal to transmit a plurality of data, including the data with the timing constraint, simultaneously via the high-speed serial bus.
摘要:
An image forming apparatus includes an image input device that reads an image to obtain image data and a printer engine that forms an image on a medium based on image data. A bus of a PCI Express standard is used to transfer data. Storage areas serving as end points of the standard and hardware resources that transmit data and receive image data to and from the storage areas are connected to an identical switch according to the PCI Express standard. Specifically, an input/output area, an image input device, and a printer engine are connected to one switch, and a storage area, a compressor, and a hard disk is connected to another switch.
摘要:
A data transferring system, in which processes to match settings between devices mutually communicating are simplified, software for the processes is also simplified, and the amount of data to be processed is reduced, is disclosed. In a data transferring system of the PCI Express standard, when settings between facing ports of a switch and an end point are changed, a setting change is transmitted to the port of the end point being one of the facing ports by a configuration request. The port of the end point transmits the setting change to the port of the switch by a message request and the port of the switch executes the setting change. The port of the switch sends a completion message signifying the setting change completion to the port of the end point by a message request. The port of the end point executes the setting change.
摘要:
A data transferring system based on the PCI Express standard in which power saving is realized is disclosed. In the data transferring system, a data transferring device transfers image data based on the PCI Express standard by synchronizing with a line synchronizing signal LSYNC. At this time, the data transferring device causes a period between packets (image data) to be transferred in one line cycle of the line synchronizing signal LSYNC to be shorter than a transition period “t1” which is required to transit from a link state L0 to a link state L0s and from the link state L0s to the link state L0. With this, the number of the transition periods “t1” is reduced and the period of the link state L0s is made long.
摘要:
A communication apparatus for carrying out communications to and from an external apparatus that includes a first interconnecting unit and a first non-transparent port and effects an interconnection for communications via the first non-transparent port is provided. The communication apparatus includes a second interconnecting unit that includes a second non-transparent port communicably connected to the first non-transparent port. The second interconnecting unit effects an interconnection for communications via the second non-transparent port. The second interconnecting unit performs, when the communication apparatus carries out communications to and from the external apparatus, address translation between an address for use by the communication apparatus and an address for use by the second non-transparent port.
摘要:
A memory control apparatus that controls writing and reading of data to/from a memory. The memory control apparatus includes: a sequence control unit that receives a packet sequence including a write packet including a write request of data and a read packet including a read request of the data, and changes an arrangement of the write packet and the read packet included in the packet sequence so that a first predetermined number of write packets are arranged successively and a second predetermined number of read packets are arranged successively; and a command output unit that receives the packet sequence from the sequence control unit, and outputs a write command according to the write packet and an a read command according to the read packet to the memory, in accordance with an order of arrangement of the write packet and the read packet.
摘要:
A memory control apparatus that controls writing and reading of data to/from a memory. The memory control apparatus includes: a sequence control unit that receives a packet sequence including a write packet including a write request of data and a read packet including a read request of the data, and changes an arrangement of the write packet and the read packet included in the packet sequence so that a first predetermined number of write packets are arranged successively and a second predetermined number of read packets are arranged successively; and a command output unit that receives the packet sequence from the sequence control unit, and outputs a write command according to the write packet and an a read command according to the read packet to the memory, in accordance with an order of arrangement of the write packet and the read packet.
摘要:
A plotter repeats a process of standing by until the next line synchronization timing after data transfer for one line and transferring DMAC control information requesting data transfer for one line to an MCH for each line synchronization timing whereby image data for one page is transferred. Therefore, data transfer from the MCH to the plotter is processed by continuous posted requests, so that float with respect to a line period can be made longer without transmitting a plurality of data transfer requests from the plotter to the MCH in the split method. Thus, a high data transfer performance can be realized with an inexpensive circuit because the cost for mounting a buffer memory or the like on the circuit is not needed.
摘要:
A data transfer system using a high-speed serial interface system that forms a tree structure in which point-to-point communication channels are established for data sending and data receiving independently is provided. The data transfer system includes plural end points each having plural upper ports each of which is connected to a switch of an upper side, wherein each end point includes a port selecting part for selecting a port to be used according to an operation mode of the data transfer system so as to dynamically change the tree structure.