摘要:
A display control system with a control of background luminance or color data applicable for a personal computer with a paper-white type display device includes a character video signal generation unit, a background luminance setting register, a video enable signal generation unit, a video signal priority unit, and a video signal synthesis unit. A first video enable signal from the video enable signal generation unit controls the supply of the video signals to the video signal priority unit. A second video enable signal from the video enable signal generation unit controls a display of background in a background luminance tone or color designated by the background luminance setting register for an intermediate range when the character video signal is absent.
摘要:
Disclosed is a display data transfer control apparatus in which a line control memory which can preset raster count data for modifying, in units of lines, an address of a main storage storing a character font to be displayed and character attribute data are provided, and a transfer line in the character font is determined for each line transfer in a DMA transfer sequence, so that, e.g., multi font control, character vertical elongation control, and ruled line vertical extension control, as well as processing character attributes such as an underline and overline, can be realized in the DMA transfer sequence.
摘要:
In a data processor for handling data comprising words of n-bits, a plurality of (n+m)-bit registers is provided for use as general purpose and address expansion registers, and effective addresss of (n+m)-bits are generated by adding addresses having n bits and provided in the instructions with the (n+m)-bit content of registers designated by the instructions. Thus, a data processor can be designed so as to have an expandable address bit length and flexible addressing with little additional hardware.
摘要:
A plurality of processors use a common memory under a time division control mode by way of a time division data bus. In the multiprocessor system, flip-flops are mounted for holding respective write permission flags. Also, a logic gate is employed, operative to allow the processor to write data in the common memory when both the write permission flag and the write request signal from the processor are generated simultaneously. Further, multiplexers are used so that the write operation can be achieved under the time division control mode.
摘要:
A data processing system includes three resources, i.e., a memory, a general purpose register file having a plurality of elements and a stack having a top. The system further includes a first mechanism for making the top of the stack correspond to at least one of the elements in the general purpose register and a second mechanism for controlling the operation of the stack. When the element to which the top of the stack corresponds is specified in an instruction register of the system, the top of the stack is selected to be accessed by the first mechanism and the operation of the stack is controlled by the second mechanism.
摘要:
In a multiprocessor system having a plurality of processors, each of identical construction, each processor is internally equipped with a fixed address supply source which generates a non-unique fixed address for accessing a common memory unit over commonly connected bus lines, and a sequential state indicate signal generator for generating a logic "1" or "0" synchronizing signal when a special condition (for example, interrupt) occurs with respect to the processor.A shared memory access control system for a multiprocessor system, as above described, includes circuitry, external to and associated with at least each processor except for one processor, responsive to the synchronizing signal from its respective processor for modifying the non-unique fixed address from the respective processor so that, as a result, each processor is able to address the common memory over the commonly connected bus lines with a unique fixed address.
摘要:
A computer system including a first computer unit processing user's tasks, a second computer unit performing a halt operation for a virtual memory access, a main memory storing a plurality of virtual accessing data, a buffer memory unit temporarily storing a part of the virtual accessing data and having a faster operation time than that of the main memory, and a control unit controlling the above. The buffer memory unit receives a virtual memory address from the first computer unit and outputs a corresponding actual memory address for accessing the main memory. The control unit includes first and second latches and outputs a bi-state interruption signal and a multilevel interruption signal in response to states of the first and second latch circuits. The first latch is set when a corresponding virtual access data is invalid so that the second computer unit is operated in response to the bi-state interruption signal to store a corresponding virtual access data in the main memory unit into the buffer memory unit. The second latch is set when the corresponding virtual access data in the main memory unit to be stored into the buffer memory unit is erroneous so that the multilevel interruption signal is output from the control unit to the first computer unit to terminate the operation of the virtual memory access.
摘要:
A display control apparatus using a bit map method, for controlling character attribute data, such as an underline and an overline. In the apparatus, a line control memory is arranged to preset information of character attributes in units of lines of character fonts to be transferred to a video memory; in a DMA transfer sequence of a DMA transfer controller. Character attribute control is performed in a character controller for each line transfer according to the attribute information read out from the line control memory, and expansion of a character font from a character font memory area to the video memory can be simultaneously performed with processing of character attributes from the line control memory.