Patent ID: 7882273
Filing Date: 2011-02-01
Classification: G06F,G06T

Abstract:
1. A data transfer system having a host apparatus and an image forming apparatus connected thereto by a bus, the host apparatus including: a memory device; a command separate/storage unit that separates an image forming command set, which is a set of a plurality of context commands relating to setting of an operation mode needed for image forming and object commands for specifying an image forming target, into a context command set including a plurality of context commands contained in the image forming command set, and an object command set including a plurality of object commands contained in the image forming command set, and stores the context command set and the object command set in the memory device; and a command read instruction transmission unit that transmits a command read instruction including a transfer size of each of the context command set and the object command set, and a storage address thereof in the memory device to the image forming apparatus, the image forming apparatus including a memory access controller that receives the command read instruction, and reads the context command set and the object command set from the memory device according to a content of the command read instruction, the memory access controller having a command information hold unit that holds the storage address of the context command set included in the command read instruction received, and the read context command set, wherein the memory access controller is configured to compare the storage address of the context command set included in the command read instruction with a storage address of a previous context command set held in the command information hold unit, and read the context command set from the memory device according to the storage address of the context command set relating to present reception when both of the storage addresses differ from each other, and not read the context command set when the storage addresses are the same.