| 摘要 |
PURPOSE:To quickly restore a microprocessor circuit to its initial state at the time of applying program reading operation to an area where no program is stored out of a program storing space due to any cause by storing the operation codes of an unconditional transfer instruction word in the unused area of the program storing space. CONSTITUTION:The operation codes of the unconditional transfer instruction word is stored in the unused area 5 of the program storing space and an initializing program is stored in an area started from an address corresponding to a value obtained at the time of arranging the operation codes corresponding to the number of constitutionial words of its address part. It the program reading operation is applied to an area (unused area) 5 storing no program out of the program storing space due to any cause, continuous operation codes corresponding to (the number of words constituting the address part of the unconditional transfer instruction word + 1) are read out as one instruction word and executed. Consequently, the runaway of the microprocessor or unfavorable influence or the like to a controlled object can be previously suppressed. |
