USB component and ECIOs

[echase]

http://zone.ni.com/devzone/cda/tut/p/id/3677#toc2
tells me that there is a free/lite version of Labview called LabVIEW SignalExpress LE which seems to provide all the functionality I would need in a datalogger. I.e. display lots of graphs of the live A/D input data read from the PIC/ECIO and export/save them to PC. Its limitation (not in payed for versions) is that it can not then read this saved data back to look at it later for analysis. This would be a disadvantage, but maybe the data could be read with something else like Excel.

So if I was to buy your ECIO28P or 40P do you have all the drivers I need to read up to 10/13 voltages with it and transfer them to this version of Labview, without my having to do any VB or DLL programming? And can I also get Labview to change the scaling of the input by say telling an ECIO digital output to switch a relay to alter some scaling resistors?

[Benj]

Hello

You may be better off using VB 2008. There is an express version that is free that allows you to save etc.

The ECIO28 and ECIO40 devices have sample drivers that work with the USB components in Flowcode.

Using Labview or VB and Flowcode is fairly easy and what you are explaining sounds fairly simple to acheive.

[goldwingers]

I believe Labview needs to be connected to a PLC to operate. I dont think it will operate directly with a PIC

[Benj]

Labview can communicate via a COM port serial connection (USB Serial / RS232), Via a DLL (USB Slave) or via HID (USBHID). There are other ways but I wont go into them here. For the serial to work correctly you have to make sure you have installed the VISA runtime package.

[echase]

Have ordered a ECIO40P.

You provide an excellent range of drivers and examples, but the sheer volume of them does leave me a little confused. So what is the difference between:-

• The USB driver
• The DLL
• The .IN file that Flowcode generates?

E.g. in your excellent training video Control Panel knew that your ECIO hardware was called Ben’s Keypad – where did it get that name from when it’s not the name of your IN file?

Also the difference between a runtime version of Labview and Labview Express LE (the free version)? Is it like the difference between a read only version of Adobe Acrobat that can read PDF files, but can’t edit them, and the full version that can edit them?

So will the runtime only run the sample ‘configuration’ files (i.e. files that tell Labview how to display and process data coming from the ECIO) that you have generated. Thus I am unable to modify this configuration to suit my datalogger’s design. Will these ‘configuration’ files work with the Labview Express LE version, assuming they don’t ask it to use a function that is not in this Lite version, so I can edit them?

Sounds as if I need to use it as a USB slave but what is a HID?

[Steve]

You don't necessarily need to go with LabView. There is a similar product called ProfiLab. The makers of ProfiLab also make something called "RealView" which is cheaper and might be what you are looking for.

[echase]

ProfiLab looks good but don’t see any ECIOs in the list of supported products so how would interfacing be done? Who provides the DLL, .IN or whatever is needed to get the ECIO to talk to ProfiLab?

[Steve]

We're currently looking at how to do this. One option is to implement your own protocol over a virtual COM port using the USBSerial component, which can then be accessed by ProfiLab. You should be able to do this immediately.

We are also looking at the possibility of creating a custom DLL that works with ProfiLab directly.

[echase]

One problem with ProfiLab is that it does not look as if it's been updated for 4 years so will it work with Vista and Windows 7 and will they clear any new bugs? Up to XP only is listed as compatible. I use XP.

[echase]

Labview can communicate via a COM port serial connection (USB Serial / RS232), Via a DLL (USB Slave) or via HID (USBHID). There are other ways but I wont go into them here. For the serial to work correctly you have to make sure you have installed the VISA runtime package.

Are you saying then that it will not work in XP? Wife has a Vista laptop but will not be pleased wth my hijacking it!

THink I will be using USB slave but all depends what support/drivers/DLLs you have provided.

What is HID?

[Benj]

Hello

1) The VISA runtime package is a labview plugin. The USB works on windows 2000 right the way through to windows 7. You should have no problems on XP.

2) The USB slave communicates via a DLL which is available as part of the USB pack (v3) or part of the examples pack (v4). There is also a complete driver included in the examples.

3) HID stands for Human Interface Device, normally this applies to keyboards and mice etc but you can also create joysticks, speakers, custom devices etc.

[echase]

The Labview examples you supply say they need the v8 runtime engine, implying that they won’t run with any other version. Is there any reason they won’t work with the latest Labview Signal Express LE v9 which also contains a runtime engine, but not sure which version. At one point in my installation it listed it as v7.1.1 but elsewhere it seemed to be at least v8 or maybe v9. When I clicked on the Labview file in your USB serial examples it certainly opened with the part of my Labview Signal Express LE (there are 81 separate bits/plugins/sub-programmes in it!) but I need to go through your help files to work out what your example is actually supposed to do.

Have my ECIO40P now and have it working with your sample file but need to work out how to interface with Labview. I fear that your help files, whilst useful will not help enough. E.g. Labview Signal Express LE is expecting the connected hardware to conform the NI’s IVI standard so not clear how an ECIO can be made to look like one or how to get it to recognise other than IVI.

See http://www.vektrex.com/Support/kb/Instr ... rivers.PDF for ‘tutorial’ on IVI.

[Benj]

Hello

The Labview examples you supply say they need the v8 runtime engine, implying that they won’t run with any other version.

To run the precompiled Labview examples you must use v8.0 of the runtime. To load the example .vi files simply requires a version of Labview 8.0 or later.

Labview Signal Express LE is expecting the connected hardware to conform the NI’s IVI standard so not clear how an ECIO can be made to look like one or how to get it to recognise other than IVI.

I have not used Labview signal express but it does sound like it may be a NI hardware only item.

If you can use the DLL interface VI then you can use the USB slave component on an ECIO.

If you can use VISA or Serial VI's then you can use the USB serial on an ECIO.

[Benj]

The document you linked does talk about VISA serial so you should at least be able to get the USB serial component up and running.