Patent ID: 7822949

Claim:
A command supply device that supplies, to a central processing unit, a command read out from a main memory, said device comprising: a first buffer in which said command supply device accumulates a first partial command sequence that is a head part of a first command sequence repeatedly supplied to the central processing unit from among command sequences stored in the main memory, before supplying the first command sequence to the central processing unit again; a second buffer in which said command supply device accumulates a second partial command sequence that follows the first partial command sequence while supplying the first partial command sequence accumulated in said first buffer to the central processing unit, when repeatedly supplying the first command sequence to the central processing unit; and a selection unit operable to supply to the central processing unit a command from the second partial command sequence accumulated in said second buffer, when the entirety of the first partial command sequence has been supplied to the central processing unit, wherein a first command is stored in the main memory, the first command including a location of the first command sequence and information for identifying the first partial command sequence as a command sequence to be accumulated in said first buffer, said command supply device is further operable to receive an instruction based on the information included in the first command from the central processing unit which has executed the first command, and to accumulate the first partial command sequence into said first buffer according to the received instruction, a first branch command included in the first command sequence is stored in the main memory, the first branch command executing branching to a command included in the first command sequence, and said command supply device is operable to supply, to the central processing unit, the first partial command sequence accumulated in said first buffer when the first branch command has been executed by the central processing unit, and to accumulate, at the same time, the second partial command sequence into said second buffer when the first branch command has been executed by the central processing unit and when the second partial command sequence is not accumulated in said second buffer.