A terminal includes a rotary button bracket including a dial button and a penetrating member; a housing including a penetrating hole and a click notch, the click notch being disposed around the penetrating hole; and a click bracket having a click protrusion and a planar portion, the click protrusion being configured to engage the click notch. A, M, W, R1, R2, R6, R7 have meanings given in the description. The locking mechanism is moveable from a first position to a second position. Also disclosed is a computerized method that accomplishes the method of the operating system and a computer readable media that includes a set of instructions for accomplishing the method.