CONTROLLER HAVING WATCH DOG TIMER FUNCTION

摘要

PURPOSE: A controller having a watch dog timer function is provided to enable a user to solve an error on an execution of a program rapidly by outputting a generated moment and an address of the error to an internal register and an external port when the error is generated in executing the program. CONSTITUTION: A timer register(10) counts a machine cycle from a jump command to the next jump command. A timer-capture register(20) stores the number of machine cycles of the smallest loop. A jump-address register(30) loads an address in each jump command. A jump-address-capture register(40) stores a jump command address of the smallest loop. A loop register(50) counts a repeating number of the smallest loop. A define register(60) displays the maximum loop repeating number defined by a user. A debug register(70) displays the number of Internet resets cased by an endless loop. A comparator(80) outputs a reset signal when values of the timer register(10), the timer-capture register(20), the loop register(50), and the define register(60) are identified.