TCP/IP between the Host PC and Real-Time Series Hardware

TCP/IP is an industry standard protocol for communication over networks. Host LabVIEW Real-Time VIs can communicate with RT Engine VIs using the LabVIEW TCP/IP functions. Refer to Chapter 48, TCP VIs, of the Function and VI Reference Manual for more information about the TCP/IP functions. LabVIEW Real-Time (RT) extends the capability of the existing TCP/IP functions so you can use these VIs to communicate to networked RT Series devices and across shared memory to RT Series DAQ devices. To use TCP/IP, you must supply the network address of your RT Series hardware. To communicate with an RT Series DAQ device, use DAQ:: X, where X is the device number of the processor board that runs the LabVIEW RT code.

If the real-time application calls for high-speed transfer of data to the host PC, TCP/IP communication between the host PC and RT Series hardware should be performed in a separate non time-critical loop with the aid of a Real-Time (RT) FIFO or global variables. The RT Series hardware can run a time-critical loop that writes to a RT FIFO or global variable. Meanwhile, a parallel non time-critical loop in the same VI can read from the RT FIFO or global and then write this information through TCP/IP to the host PC. Conversely, the host PC could write to a non time-critical loop on RT Series hardware via TCP/IP. The non time-critical loop could then write this data to a RT FIFO or global, while the time-critical loop reads from the RT FIFO or global.



Related Links:
Real-Time FIFO Example
Real-Time FIFO for Deterministic Data Transfer Between VIs.

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