communication through serial port-Timeout problem

[labview driver for agilent 8720ES S-para]

Hi Guys,

I tried to control PM341 micro controller through serial port. When I tried to configure it always show me the time out error message. It says Error-1073807339 occurred at visa read in,

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

I couldn't solve this problem. I have used simple serial write and read. Can anyone help me with this problem? I have attached the VI with this post.

Regards

Mayuren

[Albert.Geven]

Did you check your cabling with e.g. hyperterminal?

[labview driver for agilent 8720ES S-para]

The cabling and connections are ok. Because I have tried with the different code which was working. Mostly, the problem with my coding(VI). I dont really understand what does it mean by "timeout expired" and I dont know how to solve this problem. Do you have any idea about this error message?

Regards

Mayuren

[Dennis_Knutson]

Timeout expired simply means that nothing was read before the timeout setting was reached. There is a default timeout so the functions will eventually return.

Attaching a shipping example does not help. You have not provided the actual command that you sending. This is essential information - and provide the exact and entire string.

Also explain what you mean by 'different code which was working'. Is this a terminal emulation program such as Hyperterminal or an application from the vendor. This is also an important distinction. An application program may take a command you enter and reformat before sending it. You need to sniff the serial port to see what is actually being sent or base your command on information in the manual. 

[labview driver for agilent 8720ES S-para]

Hi Denn,

Thanks for you reply. Basically I’m trying to control a stepper motor via PM341 Mclennan Stepper motor controller through serial communication. I have tried to download the instrumental driver software for the PM341, but I couldn’t find it.

I make the current values default, save the VI and attached with this post. I have send the right command and format to the motor through this vi.

Could you help me with this?

Regards

Mayuren

[Dennis_Knutson]

Does the motor move when you send the command? If it does, then the command is correct. If it does move, are you sure you are supposed to be able to do a read automatically or do you have send a command to request move complete or new position?

Do you have an electronic copy of the manual that you could post so someone can look at it?

[labview driver for agilent 8720ES S-para]

No, the motor didn’t move and show any response for me. MR-this command mean move relate to the current position. I don’t have the full version of the manual in the electrical format to send. I’ll just have some of the commands and details and I’ll attach with this post.

I don’t have the lab facilities during the weekend, for further communication with the motor and the micro controller I can able to do on Monday only.

Thanks for your helpRegardsMayuren

[Dennis_Knutson]

That document refers to a LabVIEW driver that it would seem Mclennan developed and does not document any of the commands you need to send to the controller. Why don't you ask Mclennan for the driver?