DAQFactory Crashing

[seth]

I am getting two errors in the command/alert window after running my program for a short amount of time (~5-10 minutes) which then causes DAQFactory to hard crash.

Unknown error adding read/write request - 2

Unknown error in Timing loop. Loop still running

Is there any way to look into what is causing these? I have checked that all of my sequences have delays in them which is all I could find online for troubleshooting.

[AzeoTech]

Unknown errors typically are caused by blown stacks, memory issues, or hardware level issues which are hard for any program to catch and avoid a hard crash.  Can you please post or email us your .ctl document so we can take a look?  My guess though is blown stack in a channel event (see below)

In general:

Blown stack: this occurs when you do something recursively.  I.e. you have a function that calls itself.  It usually isn't that obvious though.  It's usually a function X calls Y which calls Z which in turn calls X.  One way to get this in DAQFactory is if you are using a Channel Event.  So, channel X is an output and has an event.  That event calls function Y which as part of its logic sets channel X to a new value.  That in turn runs the event again...

Memory issues: these are more rare and usually only hit when you have large histories and large channel counts.  But if Task Manager is showing DAQFactory using over 1 gig you should start to pay closer attention.  Above 1.5 gig and the memory available to DAQFactory as a 32 bit app becomes quite limited for what it needs to do.

Hardware level issues: if you are calling into a DLL, either using extern() or through a driver you are running code that DAQFactory has no real control over.  In general it can capture most synchronous errors, but if the DLL starts a secondary thread, as is often done when streaming, and that thread throws an error, DAQFactory can't do anything to catch it and Windows shuts DAQFactory down.