Digital display apparatus

A digital display apparatus comprising a first comparator for detecting the difference between a piece of sampling data corresponding to a changing measurement value detected by a sensor and output as a digital signal at an interval of a predetermined period and a piece of display data corresponding to a currently displayed value on a display unit, an adder connected to said first comparator for setting addends changeable depending on both said difference and the number of times of display updates made on the display unit within a predetermined period of time, a first counter connected to said adder for accumulating said addends at intervals of said predetermined period, a second comparator connected to said first counter for comparing a predetermined reference value for determining a display updating period with said accumulated addends and instructing display updating when the value of said accumulated addends exceeds said reference value, a second counter connected to said second comparator for counting the number of times of the display updates made, and a third comparator connected to said second counter for comparing a predetermined reference value of the number of times of display updates with said number of times of the display updates made and outputting the result of the comparison to said adder, wherein it is adapted such that the display updating period is changed depending on both the difference between said sampling data and display data and said number of times of the display updates made.