How to implement the watchdog timer of the PCI 6518 with two data lines

[LT42]

Hello,

I am very new with Lab View and I need some help to figure out why I can't use the watchdog timer of my PCI 6518 for two different situations. I am using port 2.0 and port 3.0 of the PCI 6518. If I use one at the time, them the board outputs what I need. But when I try to use them both, it says Error 50103. I already read the cases for this error, but I have not been able to fix my problem. Someone told me that I needed an extra PCI 6518 because ther eis only one watchdog timer in it, is that true?

I would think there is a way to use more than one data line to activate the watchdog.

I appreciate it,

LT42

[Brian_P]

LT42,

Thank you for using the forums.  I have been able to do a little digging into this issue and after looking in the manual page 1-7, it appears that there is only one watchdog timer on the PCI 6518.  Once this resource is reserve, it has to be released in order for another task can access it.  That is why you receiving error 50103.  My initial thought was to use a switch, but that would defeat the purpose of having 2 lines because as long as one line is working the timer would continue to reset.  I believe the best solution for this issue is to use 2 cards.

I hope that helps,

Brian P.

[LT42]

Brian,

That you for your reply.

I think my issue is being able to make the watchdog timer expire from  when there is any of two independent failures. I am not trying to expire the watchdog timer more than once without reseting it first. I am trying to be able to output a low when one of the failures occurs and keep the other line high and viceversa. Right now I have line 2.0 connected to a channel (A) and line 3.0 connected to a channel (B). At the moment I believe my program can only output a low for one of them because the other one shows 50103. So, from what you are saying, there is no way to be able to have maybe two timeouts for the same watchdog timer? I thought that since the PCI had 16 outputs, maybe the watchdog timer could be programmed so that the board can output a low for on certain channel according to the reason of expiration of the watchdog timer.

Thank you,

LT42

[Brian_P]

LT42,

The watchdog timer can only moniter one line at a time.  The reason that you are getting error 50103 on one line and the other line works, is because the first line is taking that resource any other line from using that resource. 

I hope that helps.

Brian P.