| 摘要 |
PURPOSE:To eliminate an error caused by the uneven rotations of a magnetic disk, by producing a window signal through the specified period among all periods of a counter from the time of arrival of a data signal and a clock signal when separating these signals which are recorded on the magnetic disk, etc. CONSTITUTION:A preset counter 5 of 16 notation uses, e.g. SN74191 of the Texas Company, and preset inputs A-D plus count outputs QA-QD are provided with Q and QA, B and QB, D and QD plus C and CQ as weights 1, 2, 4 and 8 respectively. The counter 5 performs the counting with a clock signal CK to be supplied, and the states of the inputs A-D are set to the counter 5 with input of a load signal LO. Based on the set value, the counting is carried out. The data signal, the clock signal and the output QD, i.e. the window signal are supplied to a data separator 6 to separate the data signal. The output QD is set so as to be produced in a 1/4 or 3/4 counter period at the time when the data and clock signals arrive. |
