CONTROL CODE DETECTION CIRCUIT FOR VOICE SIGNAL

摘要

PURPOSE:To realize a simple circuit discriminating a control code added to a head of one frame of a digital voice signal. CONSTITUTION:A data is moved only for a period when a bit stream applied to a most significant digit position represents a control code in flip-flops 32A-32V. That is, a control code bit inputted from a terminal 14 to the flip-flop 32V is transferred sequentially to a same digit position of the flip-flops 32A-32V by each clock and the bit appears at the flip-flop 32A after 22 clocks when a signal (c) shown in figure 3 is valid for the control code period. Thus, a data reaching the final stage flip-flop 32A is inputted to a terminal 37B of a discrimination circuit 36 and inputted again to a digit position shifted by one lower digit of the flip-flop 32V.