1. Field of the Invention
The present invention relates to a system including a data driven processor, and more particularly, to a system including a plurality of data driven processors connected in a multi-network manner.
2. Description of the Related Art
In a conventional von Neumann computer, various instructions are prestored in a program memory as programs. The instruction is sequentially read out from an address of the program memory sequentially specified by a program counter for execution thereof.
On the other hand, a data driven processor is one type of a non-Neumann computer. The data driven processor does not have a concept of sequential execution of instructions by a program counter. The data driven processor employs an architecture based on parallel processing of instructions. In the data driven processor, when data to be subjected to operation is available, the instruction can be executed. Because a plurality of instructions are simultaneously driven by data, programs are executed in parallel according to a natural flow of data. As a result, it is considered that a time required for operation is substantially shortened by the data driven processor.
A method of connecting data driven processors associated with the present invention is taught in Japanese Patent Application No. 4-117406 (Japanese Patent Laying-Open No. 5-314284 laid open on Nov. 26, 1993) assigned to the same assignee as that of the present application. Japanese Patent Laying-Open No. 5-314284 is incorporated herein by reference. The above method of connecting the data driven processors made it possible to change programmably the destination of data provided from each data driven processor without reconnecting data driven processors.
Some problems still remain to be solved. As the number of data driven processors connected increases, a path between processors becomes longer and some processor pairs cannot exchange data directly so on and so on. The latter problem causes secondary problems. For example, processors used for relay of indirect exchange of data suffer from the overhead, a program to be stored in the processor becomes more complicated, and so on.