Patent ID: 7602389

Claim:
A data processing system comprising: a memory controller; and a memory connected to said memory controller, said memory having a common logical address memory space; wherein said memory controller includes a rendering circuit thereby to execute a rendering command generating display data based on first graphic data provided with processing via a processing program in a processor unit (PU), and said memory controller stores said display data in said memory; and wherein said display data in said memory is stored as pixel data of color with Z value, and wherein said rendering circuit reads said Z value to compare with a Z value of data of display data based on second graphic data to be stored by said processing program into said memory, to determine whether to store display data based on said second graphic data in said memory or not; wherein data access from said PU, data access as data to be displayed by a display, and data access from said rendering circuit, are controlled by said memory controller so as to be accessed alternatively.