MAIL MACHINE WITH BUILT-IN CONTROL SYSTEM PROVIDED WITH SCREEN CONTROL ARCHITECTURE

PROBLEM TO BE SOLVED: To facilitate the grade-up of a control system, to reduce development time and cost and to reduce the request of a system resource by permitting a control program to identify a previous function to execute through the use of previous function data and a background function to execute through the use of background function data. SOLUTION: A screen previous function driver 250 processes the previous function before the display of data for the screen, initializes whole texts and data elements corresponding to the screen, makes them into a format and properly displays them. A screen background function driver 270 processes a function being independent of an action to be executed by the operator of a mail machine 10. For example, it is the poling of a mail charge meter, a dynamic measuring action (initialization, proofreading or reading or the like), the reading and updating of data related to the states of various sensors, the transmission of new screen data to a display as the result of the updating of the text or a field and communication with a printer or the like.