| 摘要 |
PURPOSE:To attain acquisition of synchronism quickly and accurately by storing the position of a finite data conversion point in the past and then by regarding the mean position of the conversion point as a correct conversion point. CONSTITUTION:Waveform-shaping circuit 1 converts input Di into a rectangular wave, which is differentiated by conversion-point pulse generating circuit 2 to apply a pulse to AND gate 5. Then, the differentiated pulse is inputted as a clock to octal counter 3 and the output of counter 3 is applied to decoder 4; every time a conversion-point pulse is inputted to counter 3, outputs 0-7 of decoder 4 is set to logic ''1'' and applied to gate 5 in sequence to select the output of circuit 2. The output of this gate 5 is applied to binary counter 6 operating by clock C1 to store the position of a past conversion point. The mean value of this stored conversion point is regarded as a correct conversion point and passed through differentiating circuit 7 to apply the pulse to coincidence pulse count circuit 8, a pulse from which drives synchronizing binary counter 11 to generate a synchronizing pulse. |
