Error -1073807339 with RS485

[bluepgt]

Hello everybody,

I'm trying to communicate to a EMCO PC TURN 50 through RS 485. I bought the RS485 to USB converter from NI and I can connect to it and I click on Communicate with Instrument in MAX. Now when I click on read I get the following error and I tried searching for it but I couldn't find anything on it.

Error shown is Error -1073807339

Thanks guys

Igor

[Dennis_Knutson]

Search results.

As you can see, there are a vast number of reasons for getting a timeout error. You should provide some more details. An instrument manual, the command you send, what you expect, whether you tested communication with Hyperterminal/vendor software, etc.

[bluepgt]

Hi,

I have used Port Monitor from sysinternals.com on the pc that is connected to the lathe. That computer is Win98 and it uses Winnc to communicate with it. The requests that are sent when I start Winnc are as follows:

VCOMM_OpenComm

VCOMM_SetupComm

and a few others. The list is on another computer so I can't post it right now.

When I try to write anything using the basic read and write example from labview and copying the settings from the old PC for port setup, I don't get anything back from it.

Thanks

[Dennis_Knutson]

At least you can verify communication with another program.

You need to run portmon on both programs and compare the differences. My guess is either formatting (i.e. you are sending ASCII instead of hex), termination, or you have sent a command that is not supposed to generate a response.

[bluepgt]

This line is different and I think is my main problem.

Old computer: RI:-1  RM:0  RC:0  WM:2  WC:100

Labview: RI:-1  RM:0  RC:0  WM:0  WC:500

Do you know what these attributes are or where can I change them. I have tried everything went through all the property node attributes but none of them refer to this. Can those maybe not be set with LabVIEW VISA at all?

Thanks

[Dennis_Knutson]

What request (IOCTL, etc.) is this?

[bluepgt]

The call is VCOMM_SetCommTimeouts. The only information that I could find and understand was that VCOMM is the old library from Win98 used to communicate through the serial port.