Title:
BUS SNOOP CONTROL CIRCUIT
Document Type and Number:
Japanese Patent JP3525771
Kind Code:
B2
Abstract:
PROBLEM TO BE SOLVED: To provide a bus snoop control circuit capable of flexibly selecting the switching of a board to be snooped and a board not to be snooped.
SOLUTION: A register 7 for simultaneously writing data into two electronic circuit boards 1 corresponding to write access from the side of host is provided for each electronic circuit board 1, and a base address 201 of 2 bits in the address showing the electronic circuit board 1 to be accessed is compared with a base address register 3 by an address comparator circuit 4. When this comparison shows coincidence, the electronic circuit board 1 has a bus control circuit 5 and a register control circuit 6 to be operating objects and becomes the operating object of data write. Thus, the electronic circuit board 1 of the write object can be selected together with the transfer of data, and the board to be snooped and the board not to be snooped can be flexibly switched.
Inventors:
Tanaka, Yukihiro
Application Number:
JP34062398A
Publication Date:
May 10, 2004
Filing Date:
November 30, 1998
Export Citation:
Assignee:
NEC CORP
International Classes:
G06F13/38; G06F12/08; G06F13/14; G06F13/42; (IPC1-7): G06F13/38; G06F13/14
Attorney, Agent or Firm:
丸山 隆夫