HDB3码 连“0”个数计数 V脉冲位置记录变量B脉冲位置记录变量 让0000的最后一个0改变为与前一个非零符号相同极性的符号-Even HDB3 code " 0"　count the number of pulse position record variable B V pulse position to make 0000 a record variable is changed to 0 and the last one before a non-zero symbol of the same polarity sign ......