Display control system

Claim 2

A display control system comprising: means (30) for setting up values of the X coordinate in a display unit (5); means (31) for setting up values of the Y coordinate in said display unit (5); and means (32) for converting or composing said set-up values of said X, Y coordinates into the physical addresses of a display memory (4), characterised in that memory access data for reading, modifying or writing into the contents of said display memory (4) is specified for said X, Y coordinates.

Claim 3

A display control system comprising: means (30) for setting up values of the X coordinate in a display unit (5); means (31) for setting up values of the Y coordinate in said display unit (5); and means (32) for converting or composing said set-up values on said X, Y coordinates into the physical addresses of a display memory (4); characterised in that X coordinate comparison means (40) is provided for comparing said values on said X coordinate with a maximum value on said X coordinate that is determined according to the screen configuration of said display unit (5); in that Y coordinate comparison means (41) is provided for comparing said values on said Y coordinate with a maximum value on said Y coordinate that is determined according to the screen configuration of said display unit (5); in that means is provided for informing a CPU (1) of the results compared by said X and Y coordinate comparison means (33); in that memory access data for reading, modifying or writing the contents of said display memory (4) is specified for said X, Y coordinates respectively, and in that said CPU (1) is informed if the X, Y coordinates to be accessed are present outside the limit of said screen (5).

Claim 4

A display control system comprising: means (30) for setting up values of the X coordinate in a display unit (5); means (31) for setting up values of the Y coordinate in said display unit (5); and means (32) for converting or composing said set-up values on said X, Y coordinates into the physical addresses of a display memory (4); characterised in that X coordinate comparison means (40) is provided for comparing said values on said X coordinate with a maximum value on said X coordinate that is determined according to the screen configuration of said display unit (5); in that Y coordinate comparison means (41) is provided for comparing said values on said Y coordinate with a maximum value on said Y coordinate that is determined according to the screen configuration of said display unit (5); in that means is provided for informing a CPU (1) of the results compared by said X and Y coordinate comparison means (33); in that memory access data for reading, modifying or writing the contents of said display memory (4) is specified for said X, Y coordinates respectively, and in that said CPU (1) is informed if the X, Y coordinates to be accessed are present outside the limit of said screen (5).

Claim 5

A display control system as claimed in claim 2, characterised in that said informing means is constructed (42) such that said CPU (1) is able to read the outputs of said X, Y coordinate comparison means as a status indication.

Claim 6

A display control system as claimed in claim 2 or 3 characterised in that said informing means is adapted to interrupt said CPU when it judges that at least one of said X, Y coordinate comparison means is greater than said maximum value.

Claim 7

A display control system comprising: means (30) for setting up values on the X coordinate in a display unit (5); means (31) for setting up values on the Y coordinate in said display unit (5); and means (32) for converting or composing said set-up values on said X, Y coordinates into the physical addresses of a display memory; characterised in that step-by-step means is provided for advancing said values of said X coordinate step by step for each access to said display memory (4), in that memory accesses for reading, modifying or writing the contents of said display memory (4) are specified on said X, Y coordinates, and that for access operations for the X coordinate direction the need for resetting said values on said X coordinate is eliminated.

Claim 8

A display control system comprising: means (30) for setting up values on the X coordinate in a display unit (5); means (31) for setting up values on the Y coordinate in said display unit (5); and means (32) for converting or composing said set-up values on said X, Y coordinates into the physical addresses of a display memory; characterised in that step-by-step means is provided for advancing said values of said X coordinate step by step for each access to said display memory (4), in that memory accesses for reading, modifying or writing the contents of said display memory (4) are specified on said X, Y coordinates, and that for access operations for the X coordinate direction the need for resetting said values on said X coordinate is eliminated.

Claim 9

A display control system comprising: means (30) for setting up values on the X coordinate in a display unit (5); means (31) for setting up values on the Y coordinate in said display unit (5); and means (32) for converting or composing said set-up values on said X, Y coordinates into the physical addresses of a display memory: characterised in that means (34) are provided for setting up a plurality of screen configurations and specifying one of said screen configurations; in that means (30c,31) is provided for changing the contents of said conversion or composition means (32) in accordance with said specified screen configuration; in that memory accesses for reading, modifying or writing the contents of said display memory (4) are specified on said X, Y coordinates, and that a plurality of screen configurations are available.

Claim 10

A display control system comprising: means (30) for setting up values on the X coordinate in a display unit (5); means (31) for setting up values on the Y coordinate in said display unit (5); and means (32) for converting or composing said set-up values on said X, Y coordinates into the physical addresses of a display memory: characterised in that means (34) are provided for setting up a plurality of screen configurations and specifying one of said screen configurations; in that means (30c,31) is provided for changing the contents of said conversion or composition means (32) in accordance with said specified screen configuration; in that memory accesses for reading, modifying or writing the contents of said display memory (4) are specified on said X, Y coordinates, and that a plurality of screen configurations are available.

Claim 11

A display control system comprising: means (30) for setting up values on the X coordinate in a display unit (5); means (31) for setting up values on the Y coordinate in said display unit (5); and means (32) for converting or composing said set-up values on said X, Y coordinates into the physical addresses of a display memory 4; characterised in that step-by-step means is provided for advancing said values of said X coordinate for each access to said display memory (4); in that means (34) is provided for specifying count modes; means (30c) is provided which is responsive to said memory access based on said specification for generating a pulse signal for count-up or count-down: in that memory accesses for reading, modifying or writing the contents of said display memory (4) are specified on said X, Y coordinates, and in that various count modes can be realized corresponding to said memory accesses.

Claim 12

A display control system comprising: means (30) for setting up values on the X coordinate in a display unit (5); means (31) for setting up values on the Y coordinate in said display unit (5); and means (32) for converting or composing said set-up values on said X, Y coordinates into the physical addresses of a display memory 4; characterised in that step-by-step means is provided for advancing said values of said X coordinate for each access to said display memory (4); in that means (34) is provided for specifying count modes; means (30c) is provided which is responsive to said memory access based on said specification for generating a pulse signal for count-up or count-down: in that memory accesses for reading, modifying or writing the contents of said display memory (4) are specified on said X, Y coordinates, and in that various count modes can be realized corresponding to said memory accesses.