| 摘要 |
<p>A method and circuit for finding the beginning of valid coded information from a scanner reading a label such as the Universal Product Code (UPC) label establishes a plurality of counting gates based on a predetermined sequence of discrete signal transitions and counts a plurality of related pulse frequencies during the gating periods under control of the established counting gates. The accumulated counts are compared in a predetermined sequence to determine whether selected counts when compared bear a predetermined relationship to each other and a code generated indicative of the relationship which indicates the beginning of valid label data or invalid label data on a continuous basis.</p> |
