| 摘要 |
PURPOSE:To ensure correct seeking action by adding a track loss signal corresponding to time interval when read track loss signal is longer than previous time interval. CONSTITUTION:When N-th pulse is counted 6 and (N+1)th pulse is outputted from an AND circuit 4, it is counted 6 through an AND circuit 5. When interval value between input pulses is (m), a counter 8 counts it by reference pulse from a generator 7 and gives it to a divider circuit 10. The circuit 10 divides the value (m) by previous value (m) in a memory circuit 11, and gives it to a -1 circuit 12 as +1 signal. When (N+2)th pulse is outputted from the circuit 4, this is counted 6 and counted 8 as about 2m and given to the circuit 10. The circuit 10 divides the value 2m by the value (m) of the circuit 11 and gives it to a circuit 12 as a +2 signal. The circuit 12 gives the +1 signal to a generator 13, and 1 pulse from the generator 13 is given to the counter 6, and counted as (N+3)th pulse. |
