| 摘要 |
PURPOSE:To reliably hold a running distance data, by a method wherein the integation of a running distance is such that counting for a lower digit range is performed by means of a C-MOS counter and counting for a higher digit range is conducted by means of a nonvolatile counter. CONSTITUTION:A pulse from a distance sensor 1 is counted up to 1km unit of a running distance by means of a C-MOS counter 2a. When an end around carry to 10km is made with the progress of counting, a carry device 4b reads data in a nonvolatile memory 4a, and after 1 is added, the addition is written in the nonvolatile memory 4a. A reading device 9 reads a 10km unit digit or more, out of digits indicating a running distance indicated in an indicator 3, from the nonvolatile memory 4a, and reads 1km unit digit or less from the C-MOS counter 2a to indicate them in the indicator 3. Even if an ignition switch 6 turns OFF, the C-MOS counter 2a is energized from a power source 8, and thereby details are held. The details in the nonvolatile memory 4a are held even if the nonvolatile memory 4a is not energized. |
