| 摘要 |
PURPOSE:To prevent the reading error of car type information by writing special data from a CPU at the time of the initial rise of a device, reading special data written at the time of the power failure recovery, collating them with the writing data and when the data are coincident, executing the car type information processing by the CPU. CONSTITUTION:A condition collating circuit 10 operated with a voltage a little lower than the voltage from an no-break power source 5 supplied to car type information counters 2a-2j is provided, the special data is written from a CPU to the storing part of the circuit at the time of the initial rise of the device, the written data in read and collated with the written data at the initial rise in the CPU. At the time of the coincidence, the data to invert a polarity at the time of the initial rise is written into the storing part of a condition collating circuit 10, it is checked whether or not the written data is correctly read, and it is decided that the accumulated adding value at the time of the power failure recovery of the counters 2a-2j is normal when the data is normally read. Thus, the CPU can read the correct number of the vehicles classified by the car type to pass through at the time of the power failure. |
