Patent ID: 8260872

Claim:
A data transmission system comprising: a master node comprising a master modbus simulator, a host system in communication with the master modbus simulator, and a communication interchange in communication with the master modbus simulator; a slave node comprising a slave modbus simulator, a communication interchange in communication with the slave modbus simulator, and at least one modbus device in communication with the slave modbus simulator; wherein the slave modbus simulator includes a status repository to store register data reported by the at least one modbus device, and a historical repository that stores historical events, wherein historical events are defined as register data stored on the status repository that has changed; wherein the master modbus simulator includes a status repository to store the register data received from the slave modbus simulator and a historical repository to store the historical events received from the slave modbus simulator; wherein the communication interchange of the slave node is in communication with the communication interchange of the master node; wherein the master node is configured by transmitting a query from the host system to the master modbus simulator to determine the register data that is required from the at least one modbus device connected to the slave modbus simulator; wherein the master node is initialized initializes by receiving the register data from the status repository on the slave modbus simulator; wherein the register data is related to a status of the at least one modbus device; and wherein, after the master node is configured and initialized, the historical events are transmitted from the historical repository of the slave modbus simulator to the historical repository of the master modbus simulator.