Abstract: A memory interface circuit is connectable to a DDR-SDRAM which outputs read data in synchronization with a data strobe signal together with the data strobe signal. A clock generator generates internal clock signals and memory clock signals supplied to the DDR-SDRAM. The memory interface circuit determines a delay of arrival of the data strobe signal relative to the corresponding internal clock signal by using a data strobe signal inputted in a read cycle with respect to the DDR-SDRAM, samples the arrived read data, based on a signal obtained by shifting the phase of the arrived data strobe signal, and synchronizes the sampled read data to the corresponding internal clock signal on the basis of the result of determination of the arrival delay.

Abstract: A memory interface circuit is connectable to a DDR-SDRAM which outputs read data in synchronization with a data strobe signal together with the data strobe signal. A clock generator generates internal clock signals and memory clock signals supplied to the DDR-SDRAM. The memory interface circuit determines a delay of arrival of the data strobe signal relative to the corresponding internal clock signal by using a data strobe signal inputted in a read cycle with respect to the DDR-SDRAM, samples the arrived read data, based on a signal obtained by shifting the phase of the arrived data strobe signal, and synchronizes the sampled read data to the corresponding internal clock signal on the basis of the result of determination of the arrival delay.

Abstract: A memory interface circuit is connectable to a DDR-SDRAM which outputs read data in synchronization with a data strobe signal together with the data strobe signal. A clock generator generates internal clock signals and memory clock signals supplied to the DDR-SDRAM. The memory interface circuit determines a delay of arrival of the data strobe signal relative to the corresponding internal clock signal by using a data strobe signal inputted in a read cycle with respect to the DDR-SDRAM, samples the arrived read data, based on a signal obtained by shifting the phase of the arrived data strobe signal, and synchronizes the sampled read data to the corresponding internal clock signal on the basis of the result of determination of the arrival delay.

Abstract: A multifunction system has advanced functions and high speed capability and is excellent in expandability. The multifunction system includes a controller, an IIT, an IOT, and a light distributing device. For a print job, print data outputted from the controller is converted into optical signals, which enter a light distributing device and are transmitted to the IOT of the emission side. The IOT prints the received data onto a printer. For a copy job, copy data outputted from IIT is converted into optical signals, which enter the light distributing device, and are transmitted to the IOT of the emission side. For a scan job, scan data outputted from the scanner is converted into optical signals, which enter the light distributing device, and are transmitted to the controller of the emission side. The controller processes the received data.

Abstract: A memory interface circuit is connectable to a DDR-SDRAM which outputs read data in synchronization with a data strobe signal together with the data strobe signal. A clock generator generates internal clock signals and memory clock signals supplied to the DDR-SDRAM. The memory interface circuit determines a delay of arrival of the data strobe signal relative to the corresponding internal clock signal by using a data strobe signal inputted in a read cycle with respect to the DDR-SDRAM, samples the arrived read data, based on a signal obtained by shifting the phase of the arrived data strobe signal, and synchronizes the sampled read data to the corresponding internal clock signal on the basis of the result of determination of the arrival delay.

Abstract: An image forming apparatus is divided into detachable modules such as an IOT module and an EXIT module. A circuit architecture is constructed in which a main module circuit containing a master control part for controlling the whole system and a plurality of sub-module circuits containing slave control parts controlled by the master control part are separately handled according to the respective functional parts in the apparatus. Each module circuit includes a CPU on which a common operating system is installed, and an I/O part which interfaces with functional operation parts which operate corresponding to the dedicated functional parts. The CPU and the I/O part are mounted on daughter boards, which are removably attached to a mother board. A circuit-attribute select controller part 150 selects a main module circuit or sub-module circuits.

Abstract: After parallel data is converted into serial data by the converter 402, the serial data is converted into an optical signal by the photoelectric converter 404, and this optical signal is incident on the optical fiber 410. When the optical signal passes in the optical fiber 410, it is received by the photoelectric converter 424 on the opposite side and converted into serial data. After this serial data is converted into parallel data by the converter 422, it is inputted onto the video board 427. When the optical transmission technique is adopted, even if a plurality of functional modules are arranged distant from each other, the problems of electromagnetic interference, electro magnetic emission, adaptability to the electromagnetic environment and deformation of a wave-form are not caused.

Abstract: A multifunction system has advanced functions and high speed capability and is excellent in expandability. The multifunction system includes a controller, an IIT, an IOT, and a light distributing device. For a print job, print data outputted from the controller is converted into optical signals, which enter a light distributing device and are transmitted to the IOT of the emission side. The IOT prints the received data onto a printer. For a copy job, copy data outputted from IIT is converted into optical signals, which enter the light distributing device, and are transmitted to the IOT of the emission side. For a scan job, scan data outputted from the scanner is converted into optical signals, which enter the light distributing device, and are transmitted to the controller of the emission side. The controller processes the received data.