Communication with ORIEL stepper controller 18709

[cecileaz]

Hi !

I'm trying to use a stepper controller made by ORIEL (model 18709) and control it with labview.

I couldn't find a driver for it, so I'm trying to do my own, but I had some troubles so far :

1. the stepper controller doesn't answer the question *idn?

I guess this is because it is to old, and it should not be a problem

2. I tried to send the controller a couple of basic commands that I found in the user manual with the instrument I/O assistant, but nothing happened. And the "read and parse" step always gives me the following error : "timeout expired before operation completed".

So it looks like no communication is possible so far beetween labview and the stepper controller.

Does anyone could help me trying to fix this ? I have no experience in talking to stepper controller without drivers 😉

I'm running labview 8.2.

The stepper controller is connected via the gpib port, but I could also connect it via a rs232 port.

Thanks,

cecile

[BenjaminR]

Hi Cecile,

Thanks for posting on the National Instruments Forum.

You can develop your own Plug & Play driver using VISA; you will find here all what you need to implement your PnP instrument driver. Moreover, you will find here some troubleshooting about GPIB communication. You can use Measurement and Automation Explorer (MAX) >> Interactive Control (IBIC) to test your command.

[Albert.Geven]

Hi Cecile

first try if you detect the gpib connection in MAX, *IDN is indeed probably too old.

If you see any respons in max ( with find instruments you can see that the instrument is alive)

Serial also has a problem in wiring (straight or null modem). And it can be that handshake is enabled and you have the wrong baudrate.

Gpib is much easier if you have the possibility.

goodluck

[cecileaz]

Hi !

Thank you both for your answers, I'll look into that.

Cecile

[cecileaz]

Hi !

I'm back with no progress on communicating with my stepper controller...

I tried to follow the steps I found in the documentation about develop your own Plug & Play driver using VISA. The first step "use the instrument interactively before" is ok, I played with the stepper controller and everything is working fine. So I guess this is really a communication problem.

When using MAX, the gpib connection is detected, the instrument is found and it has the primary adress I give it, so this is ok. 

Now I would like to understand how to send a command properly to my instrument. Maybe you can help me understanding the manual.

Here are the issues I have :

1. Message termination : how do I know if my computer terminates it's message with only a carriage return or if it terminates them with a carriage return + line feed ? This looks important for the communication, but I don't know how get this information or how to set it.

2. The language used as sample in the manual is a BASIC language (HP-85). What is the language used by Labview ? Can I find somewhere the equivalences between HP-85 syntax and Labview syntax ?

Thank you for your answers, this sould already help me a lot. 

Cecile

[BenjaminR]

Hi Cecile,

You can configure (Message termination) you PCI-GPIB card directly in MAX then you can use the same command you use in MAX in VISA functions. For instance you can write a string constant "*IDN?" in VISA Write.vi and then use the VISA Read.vi to get the answer of your instruments. Here you will find all what you need to implement your PnP VISA driver in LabVIEW and you can also go in Instrument IO>>Instrument Driver palette to have an example for the Agilent 34401.