Interface circuit device for performing data sampling at optimum strobe timing by using stored data window information to determine the strobe timing

DETAILED DESCRIPTION An object of the invention is to provide an interface circuit, which can accurately transfer data to any one of semiconductor devices in a system.
Another object of the invention is to provide an interface circuit, which can implement an on-board system allowing fast and accurate data transfer.
Still another object of the invention is to provide an interface circuit, which can ensure a sufficient set-up time and a sufficient hold time of data for each of on-board units when assembled on-board.
Yet another object of the invention is to provide an interface circuit, which can rapidly and accurately transfer data without increasing a cost of units in a system.
Further another object of the invention is to provide an interface circuit, which allows accurate identification of a cause of error even at the on-board level.
A further object of the invention is to provide an interface circuit for achieving an inexpensive system allowing fast and accurate data transfer regardless of the structure of the on-board system.
A particular object of the invention is to provide an inexpensive memory control device capable of fast and accurate data transfer.
An interface circuit according to the invention includes: production/storage circuitry for detecting a point of change in data on a data line, producing effective window information indicating an effective period of the data in accordance with a result of the detection, and storing the effective window information; strobe timing determining circuitry for determining a strobe timing for taking in data on the data line in accordance with the effective window information stored in the production/storage circuitry; and clock producing circuitry for producing a clock signal for taking in the data in accordance with the strobe timing determined by the strobe timing determining circuitry.
An interface circuit according to another aspect of the present invention includes: transition point detecting circuitry for detecting a point of transition in data on a data line; producing circuitry for producing effective window information indicating an effective period of the data in accordance with a transition point detected by the transition point detecting circuitry; determining circuitry for determining whether a width of the effective window satisfies a first condition; and storage circuitry for storing an address and a data pattern of the data when the determining circuitry determines that the first condition is satisfied