Control of a JULABO cryothermostat (CORIO CD) using LabView

[Iforire]

Dear NI forum members,

I would like to control a cryothermostat (JULABO CORIO CD) using a labview program.

There is a driver made available by JULABO with some examples (Software | JULABO GmbH). It was released in 2012.

I have one of the latest version of LabView (2024Q1) and I am using the 32 bits version since I have some compatibility problems with equipment I control with LabView.

The examples provided do not work. The thing is that I have to put the "external control" of the cryothermostat to ON to make it controllable and when I start the LabView program, it goes back to OFF instantly and nothing happens.

When I used the Windows program also provided by JULABO (EasyTemp, Software | JULABO GmbH), it is working perfectly (but unfortunately, it's not as tunable as a LabView program can be). So I think this is clearly possible and it might be a matter of wrong connection between LabView and the cryothermostat.

But I'm no expert at all, so I need your advices!

Also, I used MAX to try to find where the problem is. I reconfigured the virtual COM port exactly as specified in the Labview examples and I receive this answer:

Is port connected VI_ASRL_CONNECTED Invalid Property Value

What should I do?

Should I try all possible configurations (Baud rate/Flow control/ Parity/Data Bits/Stop Bits)? It will take me hours...

Any suggestion will be welcome here 🙂

Thanks a lot

[GerdW]

Hi lforire,

how do you connect the Julabo to your computer?

RS232, RS485 or USB?

Real COM port or USB-to-COM adapter?

[Iforire]

Sorry I forgot to mention. I am using a USB cable on both sides (PC and cryothermostat).

Thanks!

[GerdW]

Hi lforire,

how does the VISA resource string look like?

Does that USB connection create a virtual COM port? (I guess so.)

Can you communicate with your device using a terminal tool (like HyperTerminal)?

[Iforire]

Yes, I've attached a picture of the VI.

yes a virtual port COM5 is created.

Thanks for the suggestion HyperTerminal, I'll try that.

[GerdW]

Hi lfirore,

---

@Iforire wrote:

Yes, I've attached a picture of the VI.

---

The VISA resource name is empty: no VISA resource, no VISA communication!

[Iforire]

Sorry, I took the screen at the wrong time. Of course, I select the right COM port (5) when I am trying to connect

[Iforire]

I have tried Hyperterminal, but I do not know how to use it effectively.

I would like to check what is transfered to the cryothermostat when the EasyTemp program is running, but I cannot access to the COM since it's occupied.

Thank you

[GerdW]

Hi lfirore,

you can look into the driver VIs to read the commands send to the device!

Or read the programming manual…

HyperTerm is used as replacement to other software - you learned the COM port is NOT a shared resource!

(There are other tools that allow you to sniff the COM port communication…)

[Iforire]

Thank you!

I've downloaded another software that allowed me to monitor what's the labview and the EasyTemp programs are doing and I will try to compare. 

Thanks for the tip