Display control method and display controller and display apparatus using the same
AssigneeCanon Kabushiki Kaisha
InventorEiichi Matsuzaki
Life of this patent
Estimating the term…
Abstract
A display controller for outputting display data stored in a display memory to a display includes an address memory for storing an address, subjected to a write access, of the display memory, and a reciprocal number memory for storing a reciprocal number, calculated by a reciprocal calculator, of the number of display pixels of one horizontal line on the screen. A multiplier multiplies the address stored in the address memory with the reciprocal number calculated by the reciprocal calculator, and a horizontal line number determinator obtains a display line number of the screen on the basis of a multiplication result by the multiplier.
Claims28
A display controller for outputting display data stored in a display memory to a display so as to display the display data on a screen of the display, comprising:
- an address memory for storing a binary address, subjected to a write access, of the display memory;
- a reciprocal calculator for obtaining prime numbers of the number of display pixels of one horizontal line on the screen and for calculating a reciprocal number of the prime numbers, excluding two as a prime number;
- a multiplier for multiplying a binary address shifted in accordance with the power of two in the prime numbers with the reciprocal number calculated by said reciprocal calculator;
- and
- horizontal line number determination means for obtaining a display line number of the screen on the basis of a multiplication result by said multiplier.
A display apparatus for displaying an image, comprising:
- a display memory storing display data;
- a display unit having a screen for displaying an image based on the display data;
- write means for writing display data by accessing said display memory;
- an address memory for storing a binary address, accessed by said write means, of said display memory;
- a reciprocal calculator for obtaining prime numbers of the number of display pixels of one horizontal line on the screen and for calculating a reciprocal number of the prime numbers, excluding two as a prime number;
- a multiplier for multiplying a binary address shifted in accordance with the power of two in the prime numbers with the reciprocal number;
- line number determination means for obtaining a display line number of the screen corresponding to the address accessed by said write means on the basis of the multiplication result of said multiplier;
- and
- control means for outputting the line number determined by said line number determination means and the display data corresponding to the display line number, which is stored in said display memory on said screen, upon reception of a display request from said display unit.
A display control method for outputting display data stored in a display memory to a display unit and displaying the display data on a screen of said display unit, comprising the steps of:
- storing a binary address, subjected to a write access, of the display memory;
- obtaining prime numbers of the number of display pixels of one horizontal line on the screen and calculating a reciprocal number line of a prime number, excluding two as the prime number;
- multiplying a binary address shifted in accordance with the power of two in the prime numbers with the reciprocal number;
- and
- obtaining a display line number of the display screen corresponding to the address, subjected to the write access, of the display memory on the basis of the multiplication result.
A display apparatus, comprising:
- a display memory for storing display data;
- a display screen for displaying an image based on the display data;
- an address memory for storing a binary address, subjected to a write access, of said display memory;
- a reciprocal calculator for obtaining prime numbers of the number of display pixels of one horizontal line on the display screen and for calculating a reciprocal number of the prime numbers, excluding two as a prime number;
- a multiplier for multiplying a binary address shifted in accordance with the power of two in the prime numbers with the reciprocal number;
- line number determination means for obtaining a display line number of the display screen corresponding to the address, subjected to the write access, of the display memory on the basis of a multiplication result from said multiplier, and
- display means for displaying an image on the display screen based on the display line number and display data.
An information processing apparatus for outputting display data stored in a display memory to a display unit and displaying the display data on the display screen of the display unit, comprising:
- control means for generating display data and storing the display data into the display memory;
- an address memory for storing a binary address, subjected to a write access by said control means, of the display memory;
- a reciprocal calculator for obtaining prime numbers of the number of display pixels of one horizontal line on the display screen and for calculating a reciprocal number of the prime numbers, excluding two as a crime number;
- a multiplier for multiplying a binary address shifted in accordance with the power of two in the prime numbers with the reciprocal number;
- line number determination means for obtaining a display line number of the display screen corresponding to the address, subjected to the write access, of the display memory on the basis of a multiplication result from said multiplier;
- and
- display means for displaying an image on the display screen of the display unit based on the display line number and display data.
Dependencies are inferred from the claim text.