launch LV Real-time on target programmatically

[lmd2]

I am new to LV Real-time, we are developing real-time drivers for a bus controller (I've already coded the normal LV drivers using CLFNs), and I am trying to come up with the structure for running samples. My first thought was to have some directory of samples on the RT Target, and have a LabVIEW 'dashboard-like' interface on the host which would launch the selected sample on the remote target. But as I read up on real-time it seems that the apps are not stored on the target, but simply run on the target when launched from the project explorer(?). Is the code (VI) downloaded to the target each time a program is run?

Is there a way to programmatically download and run a VI onto a target from a LV block diagram?

thanx

lmd2 

[dan_u]

When you launch a VI from the project explorer it is downloaded into memory of the RT system. But you can have VIs stored on the RT system hard drive and call them using VI server (needs VI server to be enabled on the RT system).

To dynamically launch VIs you can download them using FTP and then use VI server to call the VI (of course, make sure all SubVIs are there as well).

Hope this helps,

Daniel

[lmd2]

thanks, but just so that I get this correct:

 When you launch a VI from the project explorer it is downloaded into memory of the RT system.

Does this remain in memory permanently - or is it re- downloaded each time it is run from the proj explorer? 

 you can have VIs stored on the RT system hard drive and call them using VI server - this can be a one-time file transfer from MAX, yes?

To dynamically launch VIs you can download them using FTP and then use VI server to call the VI  - again, is downloading a one time deal or each time it is run?

thanx for your patience

it's always an uphill battle when I tackle a new technology 

[dan_u · Accepted solution]

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lmd2 wrote:

thanks, but just so that I get this correct:

 When you launch a VI from the project explorer it is downloaded into memory of the RT system.

Does this remain in memory permanently - or is it re- downloaded each time it is run from the proj explorer? 

 

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It will remain in memory until you reboot the RT system or download other VIs from the project explorer. To just run it several times (without modifications) it doesn't have to be re-downloaded.

To launch VIs on the RT from the project explorer is really nice for debugging or testing, but if I understand your needs correctly this is not really the way to go.

You could for instance have an automatically started application on the RT target that communicates to the host via TCP/IP. The host can ask this application what samples are available. Then the host can send a command to launch a sample. The RT application will then call (dynamically, i.e. local VI server) the corresponding sample VI.

Hope this helps,

Daniel

[lmd2]

ok, my understanding just went way up

thanx for the help

lmd2 

[Newton2this]

Hi, I have a PXI-1042Q Chassis with PXI 8108, 7842R(FPGA), and 6259(DAQ) installed.  If I want to run a Host VI that I have save to my RT target (after enabling my RT target's VI server) and downloaded an FPGA VI to flash memory using RIO Device Setup can I get the downloaded FPGA VI to communicate with the Host VI with or without DMA??  The whole idea here is to create a 'stand alone' application that can be linked by ethernet or TCI/IP.  Any suggestions would be greatly appreciated.  Thanks!!  John

[A_Patel]

Hi John,

Take a look at this link. It should help.

http://zone.ni.com/devzone/cda/tut/p/id/4534

Flash

[Newton2this]

Yes, that did help!  Thank you very very much!! 🙂 John