Serial Communication in Real Time PXI 8196 embedded controller

[Simone Galigani]

Hello, can you help me?

I've to develop a real time controller application and I've to communicate with a serial device by RS232,

can use the on board RS232 in the Real Time PXI 8196 embedded controller in deterministic mode ??

I've to send and receive small messagge every 10 ms, the LabView real time and I've to syncronize the

seriale communication with the real time main task...

Thanks, Simone

[Castel]

Hi Simone,

the serial communication is not a deterministic operation also in Real Time applications. Using serial code on the Time Critical VI can cause jitter, so the determinism could not be respected. It doesn't mean that it's not possible to achieve your speed specification, you have to try to develop your application (serial and "main task") to evaluate time behavior.

I don't know which Labview version you are using and what "main task" means, but I can suggest to you to use Timed Loops to manage priority execution.

I hope this helps you.

MarcoC

[Simone Galigani]

Thanks Marco C,

I'm using LabVIEW 8.0 Developer Suite with Real-Time Module (ETS);

I've to develop an Hardware in The Loop System (HIL), and every 10 ms I must send data to a GPS costellation simulation system with RS232; the amount of data is low but if I can't control the serial communication in the real time system is a very problem; the solution to develop a (U)AR(T) realized in LabVIEW-FPGA it has too time and cost expensive at this moment and I would try a different solution.

The main priority task is the computation of a single step in the aereodinamic simulation model of the flight device.

Simone

[Castel]

Try to built a VI that peforms only the serial communication and study its time behavior. Try also to increase the priority level of the VI (up to High Priority) to evaluate the improvings.

However it's not easy to help you through forum, so I suggest you to call NI Technical Support at 02-413091 to talk with an application engineer. You can ask about me.

Marco Castellano