An application that runs on an A570 can emulate the four directional
arrow buttons on the CDTV remote control using two methods: via mouse
movements and via the four directional arrows next to the numeric
keypad.  Titles should support both methods of cursor control.  Jumping
highlights are easy to control using the arrow keys.  If the title has
a pointer, the user should be able to move it using the mouse, but, in
case the user doesn't have a mouse, titles should also allow the user
to move the pointer with the arrow keys.