| 摘要 |
PURPOSE: To obtain an improved system in which a bar code can be exactly read, and the bar code having a bar with a wide width and a narrow width can be exactly decoded by adjusting the bar code with low picture quality. CONSTITUTION: Decoding is operated by using a transition sensor 158 which functions for applying an interruption signal 162 in transition from '1' to '0' and from '0' to '1'. The signal 162 is inputted to a controller 160 in which decoding software for identifying the presence of a separator and decoding the bar code is programmed. Then, the software measures the time of interruption, and distinguishes the bar with a wide width and a narrow width by a software loop which increments a continuous width count using a counter 172. An interruption service routine reads the count on the counter 172, and stores the value in a buffer 174, and the counter is reset to zero, and a count loop is resumed. |
