PURPOSE: To safely and smoothly change and add register data by providing a sale data receiving means and a ROM where the signal outputted from this means is stored.

CONSTITUTION: A control CPU 6 reads out, for example, the classification and the quantity of sold drinking water from a control ROM in accordance with the indication from an operator or the like and outputs them as a sale data signal to a sale data printer 3 through a control interface 7. A printing CPU 8 incorporated in the sale data printer 3 receives the sale data signal through a printing interface 9 and temporarily stores printing data corresponding to the sale data signal in a printing ROM 10. The printing CPU 8 reads out printing data from the printing ROM 10 by the indication of the operator or the like and prints it on a printing display part, and it is recognized by the operator or the like.