| 摘要 |
PURPOSE:To evade erroneous information recording to a charging card completely by writing the remaining count on the charging card and returning the charging card immediately in case of a runaway of a program. CONSTITUTION:If a processor CPU causes a program runaway, an address specifying signal for specifying an unused address without fail is generated, so both inputs to a comparator CP coincide with each other to generates a fault signal E, which is supplied to the interruption terminal INT of the CPU. Therefore, when the signal is supplied to the termial INT, the operation of the CPU is jumped to an address where an emergency program is stored in a fixed memory ROM to execute the emergency program by the CPU immediately. Consequently, the remaining count is written and the card is returned immediately. Consequently, the recording of erroneous information to the charging card is prevented completely. |
