off-hook and DSC

[Ben]

This is a cross-post from the LV board found here.

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I am looking to update an old BridgeVIEW app that used the "off-hook" property that was available in Lookout Protocol drivers.

If any of you have managed to migrate an app that uses that property to LV DSC, I would be very interested in hearing about the challenges involved.

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 Thank you,

Ben

[Andy F.]

Hi Ben,

I checked into the offhook property in IAOPC servers and didn't find much else out it other than it is usually used to retain the comm port. I wasn't able to find any specific reference to offhook in Lookout. Unless other Lookout users have ideas about how to do this we might leave the DSC migration discussion on the LabVIEW board. 

Let me know if you agree. 

Andy F. 

[Ben]

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Andy F. wrote:

Hi Ben,

I checked into the offhook property in IAOPC servers and didn't find much else out it other than it is usually used to retain the comm port. I wasn't able to find any specific reference to offhook in Lookout. Unless other Lookout users have ideas about how to do this we might leave the DSC migration discussion on the LabVIEW board. 

Let me know if you agree. 

Andy F. 

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Hi Andy,

I can't agree because I did not follow your reply, sorry. Could you post again so that I can understand what you are proposing? My customer was directed too the "off-hook" property by NI explicitly to handle the demnds of their application*. So I want to find out what the migration plan for the "off-hook" property is/was.

Thank you,

Ben

* The application won E-Buisness of teh year award about 8 years ago. It is a Vendo Managed Inventrory system based on BridgeVIEW and leveraging of the serial version of FP units. In a nut shell. One of a pool of machines running this app queries a DB for sites that are due for a new measurement. When one is found the connection method (stored in the DB) is used to specify the phone number of the FP unit. Once the phone is set the Off-hook is set true and this triggered Lookout to dial-up the FP and get a fresh set of readings. Once the reading where acquired the off-hook is set false and the query start again for another customer. So...

The Off-hook property is what made this all work. Without it, I would have to re-write the Lookout part of this app myself! Concidering there are many different protocols that would have to be supported, this is no trivial task.

[Andy F.]

Ben,

Thanks for the additional information about the application. It may be helpful to post that in the other forum thread as well.

I can see how my last sentence may not be clear. I was suggesting that since this sounds more like an issue with LabVIEW instead of Lookout the discussion about how to migrate the offhook property should be done there. That is unless you will be needing to use Lookout itself during the migration. I hope this is more clear. Thanks!

Andy F. 

[jbesselm]

Ben;

In the Lookout driver objects offhook is writable datamember of the driver object. You can connect a logical value to this datamember to make a serial port modem go "off hook". Its been a while but in the past I have used this to keep the driver object from hanging up the phone after a poll. I expect it works the same when Labview is using the Lookout protocol drivers.

Jim Besselman

Control Automation, Inc.   

[Ben]

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Jim Besselman wrote:

Ben;

In the Lookout driver objects offhook is writable datamember of the driver object. You can connect a logical value to this datamember to make a serial port modem go "off hook". Its been a while but in the past I have used this to keep the driver object from hanging up the phone after a poll. I expect it works the same when Labview is using the Lookout protocol drivers.

Jim Besselman

Control Automation, Inc.   

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Hi Jim,

Your reply has the form of wht appears to be an answer. What would help is if I could see an example of "connecting to a data member of Lookout".

Thanks for your input!

Ben

[jbesselm · Accepted solution]

Ben;

The tools I have are Lookout and Labview w/DSC. IF I run a Lookout process it can act as the "Lookout protocol Drivers" For example (LV 8.5)

1. I start lookout and create a Modbus Driver object
2. Using Labview Project I creat a shared variable and bind it to the Lookout modbus driver offhook data member.
3. Create a VI with a boolean control then wire the control to the shared variable that is the off hook data member of the modbus driver object.
4. Unfortunately I'm not where I have a phone line that I can test this but I'm pretty sure this will work the same as it does in Lookout.
5. I'm a complete novice with Labview so there may be better ways to achieve this.

Attached are the screenshots I hope this helps.

Jim Besselman

[Ben]

HI Jim,

Sorry about the delay in reply. I want to just say "Thank you, Mega-Kudos! " for your posts.

They were very helpful in getting things moving. It aint done yet but at least we are moving.

Ben

[Ryan.S]

First, I want to know which driver you want to use with DSC, the Lookout protocol driver or the new NI OPC Server?

The whole application is devided into two parts, the HMI/SCADA and the driver/opc. The bridgeview and the DSC are both the HMI, while the Lookout protocol driver or the NI OPC Server are the driver part. The "off-hook" is an item of the driver in Lookout protocol driver.

DSC 8.x binds the shared variable to an item, which can be the one in Lookout protocol driver or NI OPC Server. The "off-hook" item is not a part of DSC, it is belong to the driver. We don't need to do anything for the "off-hook" property migration plan in DSC. So the problem is whether or not the driver/opc server you use has the "off-hook" item. If you still use lookout protocol driver, just create the "opc client" IO Server in LabVIEW and then bind the shared variable. I believe that the BridgeVIEW works in a similar way that it binds a control or something to the "off-hook" tag. Here you just bind the shared variable instead. The different in DSC is maybe that you need to use OPC.

If you use the new NI OPC Server, it also has the "off-hook" item for the driver.

Let me know if you are able to control the "off-hook" from LabVIEW DSC.