cFP-TC120 Conversion Time

[Software_Monkey]

Probably a stupid question (at least I hope it is) but does the relatively slow conversion time of the TC120 thermocouple module affect the responsiveness of the whole network interface module?

I plan to have up to six TC-120 modules within the same network node as other I/O and I can't afford to have any appreciable delays. The first and only time I got to try a system with an TC-120 fitted it seemed to show a sluggish response to other I/O, but it could have been something else!

TIA Tony

[Wayne.C]

Tony,

Slow update rate of cFP-TC-120 is due to the 50/60Hz filtering.  It has no effect on how fast the network interface module runs.  In my own experience, sluggish behavior happens a couple of ways.  One is during bootup.  This is when things like the Shared Variable Engine are being started.  The more variables, the longer the delay.  With a little planning, this delay can be managed.  I typically just put a delay in my startup vi to allow the SVE to be up and running before I start using the shared variables.  My units seldom get rebooted and I don't need to worry about startup delays.

One issue that has been reported by several users including me involves sluggish operation until all the I/O have been used once by the program.  NI has never given a specific cause, but the fix is to add an empty text file named "fpremote.ini" to the "ni-rt/system/" folder on the cFP.  You can use ftp to transfer the file.  Maybe one of these days NI will start shipping new units with the file included.

The last cause is simply how the code is structured.  I am my own worst enemy.