摘要:
A logical control system is provided for accommodating both single and double byte accesses to a video terminal system display memory to supply video character and visual attribute data to a video screen without limiting the quantity of visual attributes and without the needless occupation of video screen character positions by visual attribute characters.
摘要:
A logic memory control system for accommodating plural read/write requests to a video terminal display memory is provided without the need for multiplexing common busses shared by the video terminal logic devices accessing the display memory, or for compromising video terminal data transfer rates.
摘要:
Apparatus in a Cathode Ray Tube (CRT) display allows the sharing of the system bus between the microprocessor (CPU) and Direct Memory Access (DMA) devices without degrading the CPU performance by splitting the system bus cycle into an address phase and a data phase.
摘要:
A microprocessor controlled cathode ray tube display system has a plurality of peripheral devices all connected in common to a system bus. Apparatus in each peripheral device activates a single interrupt signal. A single acknowledge response signal to all the devices enables the interrupting device to place its address signals on the system bus thereby initiating a firmware routine for making the interrupting device operative with the system.
摘要:
A logic system is provided in a video system for accommodating the display of video data characters and the application of visual attributes to such characters whether occurring singularly or in fields.
摘要:
A logic system is provided in a video system for accommodating the display of both video data characters and graphic characters, and the application of visual attributes to such characters whether occurring singularly or in fields.
摘要:
Each row of video information in a display memory includes a linking character code followed by address codes representative of the address location in such display memory of a first data character of a next row of video information displayed on the CRT screen. Both row insertions and deletions may be accommodated by changing address codes under firmware control without requiring the complete rewrite of video information stored in the display memory.