Old French XY Controller

[andrewW]

I have built a Light Beam Induced Current cum I-V
characterisation setup in which data acquisition from
typical 400K pixel scans takes about 100 hours. This
acquisition is effected over a PCMCIA/GPIB interface
by LabVIEW 6.0 running on Windows 2000.

The single largest contributor to the total data
acquisition time is XY-scanning. The instrument in
question is a French fabrication XY Controller of
the type

Micro Controle Model IT6D CA2

which employs micron-precision step motors. I have
been unable to find any drivers for this instrument
as it is rather old and, to the best of my knowledge,
unsupported. I currently use a core which appears to
work though its intricacies are not clear to either
myself or others I have asked.

Does anyone have a
ny experience that may be
relevant to this XY Controller? General tips on
improving the efficiency of XY Controllers in
LabVIEW would be greatly appreciated.

Replies directly to me at

wandera@stud.ntnu.no

are invited.


Andrew

PS
Many thanks to Dennis Knutson for supplying an
invaluable pointer - and sample VI to boot - on the
issue of using the HP6632A as a variable DC voltage
source. I had grappled with the notion of a Shift
Register, but proved too much of a LabVIEW newbie
when it came to the implementation.

[Ben]

Hi Andrew,

Can you chase down the command documentation for the microsteppers? gpib is rather straight-forward in LV.

Ben

[mat38]

Hello,

I have the same problem than andreww, does anyone have a solution? Does anyone know gpib commands to pilote a Micro-Controle IT6DCA?

Thanks,

Matthew

[mat38]

I've finally found the solution. For the axis 1:

    I1=+XXXX! :to move the axis of XXXXpoints.

    I1O to go back to zero (O the letter)

    I1? to ask the state of the axis 1.

    C1O et C1? for the face.

the same commandes with 2 instead of 1 for the second motor

Possible answers are AR1 (:move finished) DE1 (move) RO1(go back to zero) and  F-1/F+1 (end stop)

The commands must finish with a LF procedure.

[SolarG]

I am on a similar situation as well, although one step back.

I followed the posts in order to find a way to communicate with the Micro-controlle ID6DCA2 but it seems that the GPIB connection settings is not set up correctly as the device doesn't respond to the *IDN? query.

Any ideas or suggestions on where the correct settings (PAD, SAD, etc) can be?

Giorgos

[Dennis_Knutson]

---

@SolarG wrote:

I am on a similar situation as well, although one step back.

I followed the posts in order to find a way to communicate with the Micro-controlle ID6DCA2 but it seems that the GPIB connection settings is not set up correctly as the device doesn't respond to the *IDN? query.

Any ideas or suggestions on where the correct settings (PAD, SAD, etc) can be?

Giorgos

---

Is it supposed to? Do you see the *IDN? query listed in the programming manual? If it's not listed, then of course it will not respond to it and there is not actually a problem.

[SolarG]

Right, I found the list of commands and tested some of the commands that I need succesfully through NI-488.2 ibic.

The problem now is that although each (ibwrt) command is accepted and written in my instrument one by one, multiple commands through copy-paste are not written but only the first two.

Any suggestions to write the commands through ibic or any other NI application?

[Dennis_Knutson]

If you are trying multiple commands with a single VISA Write in LabVIEW, you need to know how and if the instrument supports this. This should also be listed in the manual. A common method is to separate the commands with a ';' (semi-colon) but using a separate VISA Write for each command is acceptable. The commands can be placed in a string array that is passed to the VISA Write inside a for loop.

I mention VISA instead of the low level GPIB functions because VISA is the preferred api. It is portable between different communications protocols (i.e. serial, gpib, ethernet, usb) and different hardware vendors (i.e. NI GPIB versus Agilent GPIB controller).