摘要 |
<p>A graphics display apparatus using a character generation architecture is disclosed. A font memory is disclosed which can be addressed to provide a different character for each character position on a display screen. In this manner graphics images can be manipulated at character generation speeds. Further, memory can be more efficiently used and font registers and additional pages of memory are not required to accommodate an expanded font list. In accordance with the present invention, attributes are generated in hardware so that the base text can remain unchanged even though the attributes of the text are changed. A unique echo circuit is provided to generate a bold faced attribute, including an anti-smear function. In the preferred embodiment of the present invention, a single memory is used to store textual and font information, thus reducing the size and costs of the character generation architecture. In the preferred embodiment of the present invention, a dynamic memory is used and a refreshing scheme is provided for refreshing selected portions of the memory during the active video portions of the device operation.</p> |