be based on data like engine coolant temperature air flow crank position etc received from various sensors see fig1 b the ecm may also u201c learn about u201d the engine as the car is driven the u201c learning u201d is actually a process that the ecu uses to track the tolerance changes of the sensors and or actuators on the engine the ecm stores these u201c learned u201d values in battery backed up ram so that it doesn 39 t have to start from scratch the next time the engine is turned over in the aeronautical applications these systems ecm equivalents are popularly called as u2018 fadecs u2019 full authority digital engine control referring to fig1 a and 1b an exemplary vehicle is shown including an ecu 200 as depicted in fig1 b the ecu 200 may be configured to receive input from sensors and to receive input directly from a user e g driver of the vehicle the creation of a complete ecu 200 is an intensive process that requires rigorous planning testing and verification often times the design of the ecu 200 or parts of the ecu 200 may be aided through use visual programming language vpl model based development mbd and or graphically based executable logic in computing a visual programming language is any programming language that lets users create programs by manipulating program elements graphically rather than by specifying them textually vpl allows programming with visual expressions spatial arrangements of text and graphic symbols used either as elements of syntax or secondary notation for example many vpls known as dataflow or diagrammatic programming are based on the idea of u201c boxes and arrows u201d where boxes or other screen objects are treated as entities connected by arrows lines or arcs which represent relations vpls.