HISTORY STORAGE CONTROL DEVICE IN LOGICAL DEVICE

PURPOSE:To realize the easiness of an automatic analysis by providing a circuit for detecting a fact that an access address to a control storage is the same continuously, by the number of cycles which has been determined in advance, and inhibiting write of history information by a result of this detection. CONSTITUTION:A control storage access address which has been transmitted through a signal line 12 from a control storage device is transmitted to registers 20, 21. The control storage addrss of the present cycle which has been stored in the register 20, and the control storage address of the previous cycle which has been stored in the register 21 are compared by a comparator 22, and by a result of its comparison, setting of a register 30 is controlled. An output of the register 30 is inputted to a +1 adder 31, and its output is inputted to a register 32. A value of the register 32 is given to a comparator 41, and compared with a value of a register 40 to which the value has been set in advance. By an output of the comparator 41, an FF50 is set, and by its output, write on a memory of a history storage device is inhibited.