Patent ID: 7765269

Claim:
A communications system having a single master node and a plurality of slave nodes and performing communications between said master node and said slave nodes, wherein said master node comprises: clock transmitting means for outputting a clock signal to said slave nodes; means for outputting a first communication selection signal group to said slave nodes, said first communication selection signal group comprising a plurality of signals indicating which of said slave nodes are individually selected as receiving-end communication partners for receiving data from said master node; means for outputting a second communication selection signal group to said slave nodes, said second communication selection signal group comprising a plurality of signals indicating which of said slave nodes is selected as a transmitting-end communication partner for transmitting data to said master node, said signals of said second communication selection signal group selecting no more than one slave node at a time, wherein signals of said first and second communication selection signal group are output simultaneously and in parallel from said single master node to said selected slave nodes; means for transmitting master node-issued data to said slave nodes selected as said receiving-end communication partners, in sync with said clock signal via a first common line between said master node and said slave nodes; means for taking in slave node-issued data from the one slave node selected as said transmitting-end communication partner via a second common line between said master node and said slave nodes after said master node-issued data is transmitted to said slave nodes selected as said receiving-end communication partners, wherein said slave node-issued data is received from the one slave node in sync with said clock signal; an arithmetic unit; a storage device; and transfer means for transferring data from said slave node selected as said transmitting-end communication partner to said storage device.