JPS56100571A - Facsimile transmitter - Google Patents

Abstract

PURPOSE:To perform detection operation of a significant signal with the same precision constantly, by detecting presence or absence of the significant signal and by generating a pulse for subscanning driving at the prescribed timing according to presence or absence of the significant signal. CONSTITUTION:If a significant signal does not exist in the led-out picture signal, outputs DA and DB of deciding circuit 4 become low-level, and buffer memory 13 is held in the write state continuously and waits for the write of the picture signal led out from binary circuit 3 the next period. At a fixed time after the output of counting circuit 6 is switched to the low level, motor control circuit 11 generates subscanning driving pulse. If the significant signal exists, outputs of deciding circuit 4 become high-level together, and write and read of buffer memory 13 are inhibited. Motor control circuit 11 does not generate the subscanning driving pulse. Circuit 11 generates the driving pulse at the timing of the rise of the first phase signal DA when one side output DB becomes low-level.