This setting determines whether the user window pans with the cursor when the cursor moves past the top or bottom border of the user window. DECVCCM (the sequence) is only useful when the height of the current user window is smaller than the page. The cursor must stay on the current page.
When DECVCCM is set to Yes (default), the cursor is coupled to the display for vertical movement. When the cursor moves past the top or bottom border of the user window, the window pans to keep the cursor in view.
If the cursor moves past the top of the display, the user window pans up, and new lines appear at the top of the screen while lines at the bottom move out of view.
When DECVCCM is reset, the cursor is uncoupled from the display. If the cursor moves past the top or bottom border of the user window, the cursor disappears.
This setting reflects the current terminal state of VT Vertical Cursor Coupling, which can be changed by the host. The associated default setting, saved with the model, is VT Vertical Cursor Coupling Default.