| 摘要 |
PURPOSE:To prevent program from runaway, by detecting if the content of a program counter performing the designation of address of a storage device is an even or odd number, and discriminating that the execution program is in error if the content is an odd number. CONSTITUTION:The instruction word system is constituted by taking the number of bits being a multiple of an even number of bit number constituting the content of the minimum unit of the address for the storage device as the word. An operation controller 1 reads out a program from the address of a main storage device designated for the address at a program counter 2 for sequential execution. When the program is executed normally, the output of an OR gate is zero, but if a program error takes place, 1 is applied from the least significant bit of the program counter 2, the output of the OR gate 5 is at 1, and it is applied to an interruption signal generating circuit 3, and the operating controller 1 rewrites the content of the program counter 2 to the designated address of the monitor program and interrupts the execution of the processing program. |
