Watchdog base

[JensT]

Hi all,

Two questions concerning watchdogs (e.g. for use in CRIO 9068 or 9033):

1. Is the LabView watchdog software based or hardware based?

2. Is there a header file to add watchdog functionality in c/c++?

Thanks in advance for your answers,

Jens

[JohannesM]

yes and no.

You are programming here with c API an FPGA, there are VHDL Files generated in the background and the bitfile is distributed to the hardware.

What you are basically doing is righting code to the hardware. Therefore the whole programming is in hardware, therefore it is reliable.

A watchdog is not directly included as a function, yet here:

http://zone.ni.com/reference/en-XX/help/372928G-01/

But you can very easily build one yourself. It is basically a counter which counts to a certain number and --- provided it is not resetted---   resets the target.

[Sam_Sharp]

I think the watchdog functionality built into some LabVIEW RT CompactRIOs and PXI systems is a hardware watchdog and it will reset the CompactRIO if you stop 'poking' it from within your RT application. Obviously you might not want your controller to reset if the RT application stops working which is why we generally implement our own watchdog functionality (from Windows/RT to FPGA).

[JensT]

Ok, I will build my own watchdog on the FPGA (with LabView) which is triggered by C code using the FPGA C API.

Thanks for your Answers.