how does the call library function works

[lyn]

i'm currently trying to merge both count buffered edges.vi and Dig Buf Handshake In(8255).vi together, however when i'm running the vi (as attached), i faced a "group in use" error.

I suspect that this is because there are 2 group config in the vi, one from the count buffered edges.vi(counter group config.vi) and another from the handshake.vi(digital group config.vi).

1. how does the call library function in the group config.vi works?

2. Is it possible to merge the 2 group.vi together? and how to merge it? what are the points to take note to merge them?

3. what are the possibilty of the problem if my suspect was wrong. And how should i go abt solving it??

thks

[JustinBritten]

Greetings,

The issue isn't that it is impossible to merge the two group VIs together or that there is an error in the call library node. I believe the issue is that you are using an incompatible VI with your DAQ board. The Dig Buf Handshake In (8255).vi is only compatible with boards which have the 8255 chip. The count buffered edges.vi is written for either the DAQ-STC or NI-TIO chip. You first have to determine from your DAQ board which chipset is used, and then only use an example compatible with your hardware. If you have an E-series board you will be using the DAQ-STC chip and if you have a 660x counter board you will be using the NI-TIO chip.

You didn't specify which DAQ board you have, but keep in mind that E-series boards only have one port.
Therefore, there's no real reason to group ports since there is only one. I also noticed that the front panel control for the port list in the example you attached was "0,1" which is also not valid for an E-series device due to only one port existing.

Regards,
Justin Britten

Applications Engineer
National Instruments

[lyn]

thanks Justin,

i'm using PCI-6025E with 8255 chip therefore i had a total of 4 port. the reason why i set "0,1" is to set the handshaking to read portA and PortB.

When i run the 2 vi separately, they function perfectly well. this problem occurs only when i tried to merge the 2 vi together. What could be the possible reasons then? what should i do to solve this problem?

and can i conclude that i'm using the correct hardware since both vi can function properly when running separetly?

thanks and best regards
lyn

[JustinBritten]

Lyn,

Alright, I wasn't sure which DAQ board you had. The 6025E does have extended DIO ports and uses the 8255 chip for these extended ports. The first port is part of the DAQ-STC chip.

The first port (on the DAQ-STC) is port 0. The remaining extended ports are 2-4. Therefore, if you use this VI you will need to use ports 2 and 3 which refer to PA and PB.

You will be able to merge these VIs. I just tried it at my desk. The issue is probably with the port list you are using.

Regards,
Justin