Industrial control communication network and method

Claim 2

In a communications network in which a computer gathers data from different sensor devices over a cable, the improvement comprising an interface circuit coupling a sensor device to the cable, said interface circuit including: means for receiving a message packet from said computer, said packet containing a plurality of operation commands for the sensor; means for storing the plurality sensor operation commands received by said means for receiving; means for sequentially sending data from each stored sensor operation command to the sensor device; means for storing data from the sensor device in response to each sensor operation command; and means for transmitting the response data to the computer.

Claim 3

The network in claim 1 wherein said interface further includes means for coupling a plurality of sensor devices to said interface.

Claim 4

The network as recited in claim 2 wherein said interface further includes means for determining from said message packet for which sensor device the packet is intended.

Claim 7

In a communications network having a programmable controller coupled to the network and at least one sensor coupled to the network by an interface circuit; a method for controlling the interface circuit and sensor comprising: (a) transmitting over the network to the interface circuit a message packet which contains a return code field, a command field, a field for sensor status, a field for interface circuit status, a sequence number field and sensor number field; (b) the interface circuit upon receipt of the message packet, examining the command field to determine if the command is for the interface circuit or a sensor coupled to the interface circuit; (c) if the examined command is for the sensor, the interface circuit responds by sending an instruction to the sensor regarding a task specified in the command field; (d) if the examined command is for the interface, the interface circuit responds by performing a task specified in the command field; (e) thereafter the interface circuit gathering data from either itself or the sensor in response to the performance of the task; (f) the interface circuit forming a reply message packet containing the gathered data and having a return code field, a command field, a sensor status field, an interface status field, a sequence number field, and a sensor number field; and (g) the interface circuit transmitting the reply message packet on the network.

Claim 8

In a communications network having a programmable controller coupled to the network and at least one sensor coupled to the network by an interface circuit; a method for controlling the interface circuit and sensor comprising: (a) transmitting over the network to the interface circuit a message packet which contains a return code field, a command field, a field for sensor status, a field for interface circuit status, a sequence number field and sensor number field; (b) the interface circuit upon receipt of the message packet, examining the command field to determine if the command is for the interface circuit or a sensor coupled to the interface circuit; (c) if the examined command is for the sensor, the interface circuit responds by sending an instruction to the sensor regarding a task specified in the command field; (d) if the examined command is for the interface, the interface circuit responds by performing a task specified in the command field; (e) thereafter the interface circuit gathering data from either itself or the sensor in response to the performance of the task; (f) the interface circuit forming a reply message packet containing the gathered data and having a return code field, a command field, a sensor status field, an interface status field, a sequence number field, and a sensor number field; and (g) the interface circuit transmitting the reply message packet on the network.

Claim 9

The method as recited in claim 5 wherein the contents of the sequence number field in the reply message packet are the same as the contents of the sequence number field in the message packet transmitted in step (a).

Claim 10

The method as recited in claim 5 wherein the contents of the sensor number field in the reply message packet are the same as the contents of the sensor number field in the message packet transmitted in step (a).

Claim 11

The method as recited in claim 5 wherein a plurality of sensors are coupled by the interface circuit to the network and wherein step (c) includes determining from the sensor number field the particular sensor to which the instruction should be sent.

Claim 12

The method as recited in claim 5 wherein the message packet transmitted in step (a) further includes a plurality of data blocks which specify separate operations to be performed by the sensor.

Claim 13

The method as recited in claim 9 wherein steps (c) and (d) are repeated to send instructions to and receive responses from the sensor for each operation specified in the plurality of data blocks.

Claim 14

The method as recited in claim 10 wherein the reply message packet also includes data regarding the responses received from the sensor.