undo signal export to high level

[conzemic]

Hello

I try to route a short pulse from a counter output to one of three PFIs consecutively. The lines are intended to be "high", when I change from one to the other PFI.

When I export the signal, the route will stay active, which is not what I need since the pulse will then be output to more than one line.

I have tried almost everything I knew of, including forum searches, but all I find is how to undo the exporting by setting the PFI to tri-state. this does not help as it will leave the line logically low.

All attempts to re-capture the line by a e.g. a digital output high fail on me.

Can anyone help me?

Thank you

Michael

[Alex_Pi]

Hi,

I am not quite sure what you are trying to acomplish there.

You have a Counter output and three PFIs?

What are your PFIs to have as default electical state or value? High? High impedance (tristate) is not logical low on TTL.

There is Low (connection to gnd established via pull down), High (Pull up to Vcc of TTL) and Tristate high Impedance (as if it was not connected) as for TTL elements such as DIO.

So you try to "pass" a pulse from on PFI to another? what does that look like?

Could you explain in more detail what you try to do? perhaps draw some picture and post it in your text. Once I understand what you try to do i will try to work out a solution.

[conzemic]

Hello

My application is to simluate a short line interruption in an electric sensor connector. The sensor is connected with 3 wires, each of which shall be tested individually. Logical high means line is connected. Logical low interrupts the line.

This is what i've got:

Pulse is only a few µs long. Therefore I cannot generate it from DIO but rather with a counter. As mentioned before, exporting a signal from counter to PFI works fine. However, resetting the PFI to logical high pushes me past my borders.

Hello

This is my vi-attempt.

The only vi I find to cut the export route is tristate.vi. When I try to use connect/disconnect signal VIs, I am flooded with errors stating 'route in use'.

Does that explain my problem ?

Thanks for assistance.

Michael

[conzemic · Accepted solution]

Hello

So Here is the solution I finally came up with. Not very pretty, so if anybody has suggestions for improvement, I'll be happy to learn.

Hello