Temptronics TPO4310 serial communication issue

[Elamaran]

Hi All,

I am trying to control Temptronics TPO4310 Thermalstream using serial communication. I am getting the following error when I tried to initialize

Error -1073807246 occurred at VISA Open in Temptronic TP04310.lvlib:Initialize.vi

Possible reason(s):

VISA: (Hex 0xBFFF0072) The resource is valid, but VISA cannot currently access it.

I have a USB-Serial converter to send serial command (I don't think this causes any issue because I have tried Computer with serial port also). I am using the baud rate and other serial settings in alignment with the Instrument settings(shown below). 

I couldn't figure out the issue.

Note: When I tried using GPIB it works as such without any issue.

Please help.

[Frabto]

VISA: (Hex 0xBFFF0072) The resource is valid, but VISA cannot currently access it.

                Is there any application using the serial port ?Pls check if the  Temptronics Oven set to Serial communication Mode?

[Elamaran]

Sorry I should have mentioned the following error instead, (I have closed all previous VISA references)

Error -1073807339 occurred at VISA Read in Temptronic TP04310.lvlib:Initialize.vi

Possible reason(s):

VISA: (Hex 0xBFFF0015) Timeout expired before operation completed.

VISA is getting initilized propely. But when the low level Initilize driver VI tries to query the IDN status it gets timedout and gives the above mentioned error. Simularly when I try to query the IDN status from NI MAX also it gets timedout.

I guess it is because the instruement is not responding. If anyone had faced similar issues with any kind of instrument please help.

[Frabto]

Hi Elamaran,

    Have you selected the communication mode in the Temptronics instrument from GPIB to Serial communication?.Also does the baude rate settings in the temptronics instrument match with the software settings?

[Elamaran]

Hi nijams,

I don't think there is a separate enable for GPIB/RS232 in TPO4310 instrument. We will just be able to set the GPIB address and Rs232 Baud rate.

Yes I have configured the baud rate to 9600 in both instrument and my software. But the device is still not responsive.

[Frabto]

I feel there should be some setting to inform the fimware in the instrument about the mode of communication.

I am not very much sure about this.

[Dennis_Knutson]

Have you checked to see if you are using the correct type of serial cable? There are two types - null modem and straight through.

[Elamaran]

Hi Dennis,

I am using Straight through cable only.

[Elamaran · Accepted solution]

Hi All,

I just got the interface reference document for the instrument from its support materials DVD (couldn't find on Internet). For successful serial communication with the instrument we need to use a null modem serial cable. I am yet to try it. Anyway since it is mentioned in the interface reference document I hope it will work.

Thanks for your comments.

[Frabto]

Glad that you found the solution