发明名称 |
RASTER-SCANNED CATHODE RAY TUBE DISPLAY WITH CROSS-HAIR CURSOR |
摘要 |
A raster-scanned interlaced cathode ray tube display is refreshed from a bit buffer (1). Cursor control logic (17) compares the refresh address (3, 4) with a desired cursor address and generates cursor defining bit patterns in synchronism with the bit pattern derived from the bit buffer (1). The cursor control logic (17) also generates overlay information (25) to control the mixing of the bit streams in mixers (11, 12, 13) to produce a 2 or 3-pel wide cross-hair cursor on the CRT screen. The cursor lines can be black, white or transparent. The overlay signal may also be used to control a further optional mixer combining the composite cursor bit-buffer bit patterns with bit patterns derived from a coded character buffer containing coded alphanumeric characters to be displayed. |
申请公布号 |
DE3370706(D1) |
申请公布日期 |
1987.05.07 |
申请号 |
DE19833370706 |
申请日期 |
1983.12.22 |
申请人 |
INTERNATIONAL BUSINESS MACHINES CORPORATION |
发明人 |
GOVER, DAVID JOHN;HAWES, ADRIAN JOHN |
分类号 |
G09G1/16;G09G5/08;(IPC1-7):G09G1/00 |
主分类号 |
G09G1/16 |
代理机构 |
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代理人 |
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主权项 |
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地址 |
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