Pfeiffer Vacuum - VISA Read Error -1073807298

[jcdye]

I am trying to use the Pfeiffer Vacuum LabVIEW VI to control a Pfeiffer Turbopump. I haven't changed the VI in any way, I am using them exactly how they are when you download them from Pfeiffer.

I'm using a RS485 to USB connector. All the settings are correct (baud, etc) and the device shows up in the device manager, MAX, LabVIEW, etc. The port shows up as COM3.

When I try to do Read/Write tests in VISA Interactive Control I get the error -1073807298. I get the same error when I try running the Pfeiffer LabVIEW projects.

Could there be an issue with the connector? Wiring? Drivers? (Everything shows up in Device manager and MAX)

I was able to use the NI Driver Wizard and create USB drivers for my connector. When I do this the connector shows up as a USB device and not a Serial device. I am able to run successful Read/Write tests on the device using Visa Interactive Control.

However, sense the connector shows up as a USB device and not a serial device I do not know how to reference which "COM" to use in the Pfeiffer projects. It appears the Pfeiffer projects only allow for serial connections. Is there a way to tell the Pfeiffer project to recognize the USB ports as COM (serial) ports?

[chris88]

Hi jcdye

Are you using a third party RS 485 to USB converter? If you are; take this in consideration, it might help you.

Also take a look at this since you are using a third party instrument driver.

Regarding the COM ports, USB communication protocol is serial so it has an associated COM port, you can see which COM port is associated to the device, go to Windows Device Manager and seek under Ports (COM & LPT1).

Regards

[jcdye]

I have actually tried that tutorial already, and also the one about setting the mask to 48 and buffer to 4k, none of these have seem to help. I am only using the most basic of settings, all of which the adapter claims to handle. I am not using drivers for the instrument, but only the USB-Serial Converter/adapter.

The device I am using is a third party FTDI based USB-RS485 converter.

When I use the FTDI drivers the adapter shows up in the Device Manager under Ports (COM & LPT) as USB Serial Port (COM3). However, when I test it I get the VISA read errors. (in the LabVIEW project and in VISA interactive control test)

If I use the NI-VISA Driver Wizard to make a driver for this USB device...the device is no longer under Ports (COM & LPT)...but rather under NI-VISA-USB Devices. When I look at the device manager I no longer see COM3 or where to find what COM port the device is on. But what I can do is use NI VISA Interactive Control and test the device...I no longer get the read error. However, because I cannot find the COM port that the device is on anymore...I cannot reference the device in the Pfeiffer LabVIEW projects. 

If my device is not listed under Ports (COM & LPT) in the device manager but rather under NI USB Devices how can I figure out which COM port it is under?

[Dennis_Knutson]

Using the wizard to create your own driver is just wrong. You'll have to undo everything you did.