Visual display unit with character overstrike.

摘要

A visual display unit with character overstrike capability includes a text store (1) in which text is stored in data stream form. A formatter (5) formats the stored text and loads character codes into a refresh buffer (6) which together with a character generator (7) displays the characters on a raster-scanned cathode ray tube. Control logic (15) responsive to a backspace character combines the bit patterns corresponding to the characters preceding and succeeding the backspace character in a temporary store (16) and then stores the composite bit pattern in the character generator (7) and a pointer thereto in the refresh buffer (61.

Preferably, the controt logic (15) can be inhibited to allow the individual characters constituting the composite character to be displayed individually for editing purposes.