Apparatus and method for CRT display screen

摘要

The video memory of a CRT display system is split into an application video memory and a CRT memory. The two memories are interconnected by logic means for manipulating primary and secondary texts whose characters proceed in directions which are different from each other. The character codes are applied to the application video memory. The logic manipulates the code in accordance with the rules of the primary and secondary languages and provides data to the CRT video memory for driving a CRT controller.