| 摘要 |
<p>PURPOSE: To provide a reading device excellent in correctness and productivity by counting the number of signals generated from a capstan frequency generator at one period of a control clock signal and automatically reading a mode of a refresh rate by a logical circuit. CONSTITUTION: A pulse generator 1 generates pulse signal from a control clock signal, and a frequency multiplier 2 multiplies a capstan frequency signal to output it to a counter part 3. The counter 3 pulse-counts the frequency signal, and when all the outputs are of high potential signals, a gate processing part 10 prevents the output of multiplier 2 from being impressed to the counter 3 and outputs three kinds of refresh rate discrimination control signals. A detection error correction part 20 outputs LP and EP mode discrimination signals from the control signals, and NOR gate GR6 logically harmonizes the output signal of the correction part 20 to output SP mode discrimination signal. Thus, a device capable of automatically reading a refresh rate mode with a correctness become available in a low cost.</p> |
