Local area network for distributing data communication, sensing and control signals
View Patent ↗A control network including an addressable master node having a first data port for coupling to a first component, an addressable first slave node including a second data port for coupling to a second component, and an addressable second slave node including a third data port for coupling to a third component. The master node is connected to the first slave node using a first twisted wire pair providing a point-to-point connection, the first slave node is connected to the second slave node using a point-to-point connection second twisted wire pair; and the second slave node is connected to the master node using a point-to-point connection third twisted wire pair. The network carries unidirectional digital data that may be repeated without format change by the nodes. The network wiring may carry power to power one or more of the nodes.
1. A control network comprising:
a first node including a first data port for coupling to a first component, a second node including a second data port for coupling to a second component, and a third node including a third data port for coupling to a third component, each of said nodes having a respective assigned address and a respective control unit that is addressable based on the respective assigned address;
a first twisted wire pair having two ends and comprising only two conductors, said first twisted wire pair connecting only said first node to said second node in a point-to-point connection for a first unidirectional data communication of serial digital data over said first twisted wire pair between said first node and said second node;
a second twisted wire pair having two ends and comprising only two conductors, said second twisted wire pair connecting only said second node to said third node in a point-to-point connection for a second unidirectional data communication of serial digital data over said second twisted wire pair between said second node and said third node; and
a third twisted wire pair having two ends and comprising only two conductors, said third twisted wire pair connecting only said third node to said first node in a point-to-point connection for a third unidirectional data communication of serial digital data over said third twisted wire pair between said third node and said first node,
wherein said first, second and third twisted wire pairs connect said first, second and third nodes in a ring topology,
said control units are operative, in response to control signals, to configure one of said nodes as a master node, one of said nodes as a first slave node and one of said nodes as a second slave node,
whereby said first slave node is operative to pass at least part of the serial digital data from one of said twisted wire pairs to another one of said twisted wire pairs between which said first slave node is connected; and
said second slave node is operative to pass at least part of the serial digital data from one of said twisted wire pairs to another one of said twisted wire pairs between which said second slave node is connected.
2. The network according to claim 1 , wherein said master node is operative to compare and check data received from said third wire pair versus data transmitted to said first twisted wire pair for identifying an error-free data path through said network.
3. The network according to claim 1 , wherein said first and second slave nodes are further operative to check the CRC of incoming data from a respective twisted wire pair and to generate CRC for outgoing data to a respective twisted wire pair.
4. The network according to claim 1 , wherein said first and second slave nodes are further operative to repeat without format change at least part of the serial digital data.
5. The network according to claim 1 , wherein said network is further operative for carrying network control messages over at least of said twisted wire pairs.
6. The network according to claim 1 , wherein at least one of said twisted wire pairs is connected to concurrently carry a power signal over the two conductors of said at least one of said twisted wire pairs substantially without interfering with data communication, and wherein at least part of at least one of said nodes is powered from the power signal carried over one of said twisted wire pairs connected to said at least one of said nodes.
7. The network according to claim 1 , wherein at least one of said twisted wire pairs concurrently carries a power signal over the two conductors of said one of said twisted wire pairs substantially without interfering with the data communication, and wherein at least one of the components is powered from the power signal carried over said one of said twisted wire pairs connected to the respective one of said nodes that is to be coupled to the at least one of the components.
8. The network according to claim 1 , wherein at least one of said twisted wire pairs concurrently carries a power signal over the two conductors of said one of said twisted wire pairs substantially without interfering with the data communication, and wherein at least one of said nodes is connectable to a power source for coupling the power source to the power signal.
9. The network according to claim 1 , wherein said network is further operative for analog sensing and control and further comprises an analog port and a converter for converting between analog and digital signals coupled between said analog port and said data port of one of said nodes, and wherein said analog port is couplable to an analog sensor or to an analog actuator.
10. The network according to claim 9 further operative to carry video or voice signals.
11. The network according to claim 1 in combination with a single enclosure disposed within one of the components, wherein said first node is housed in said enclosure.
12. The network according to claim 1 , wherein said network is further operative to carry data from said master node to said second slave node and from said second slave node to said first slave node.
13. The network according to claim 1 wherein said first data port is a standard DTE interface.
14. The network according to claim 13 wherein said standard DTE interface is Ethernet based.