Timeout error when multiple devices are connected

[BlueParrot]

I am trying to simultaneously control a Keithley 2000 multimeter and a Keithley 238 SMU using a GPIB-USB-HS controller with Labview, using the vi drivers supplied by Keithley (Keithley 238 Example 1.vi and Keithley 2000 Read Single.vi). On their own, they work fine if left on 'continuous run' mode.

However my programme incorporates both drivers within a 'for' loop with a time delay of 200 ms in between. After a few loops, the Keithley 2000 times out leaving a SRQ light illuminated after which it does not recover on subsequent loops. Peculiarly, if the SMU is turned off, the multimeter recovers after pressing 'continue' on the timeout error dialogue box, and subsequent loops read back sensible measurements from the Multimeter. The timeout is set to 5 seconds, which I thought should be enough.

This suggests to me that the communication from the SMU is interfering with the Multimeter in some way, though I don't know why.

Any suggestions as to why this is happening would be greatly appreciated. I am at the end of my tether!

Philip

[Tom O]

Hi Philip,

I haven't personally used these instruments in the past and this sounds very much like an issue either with your 3rd-party instruments or your 3rd-party drivers. I won't be able to help you, but hopefully someone else on the forum can!

I would try to narrow down the issue by using other (non-LabVIEW) drivers to see if it's definitely specific to the LabVIEW drivers, and get in touch with the manufacturer of the instruments and drivers for more support.

Sorry I can't be of more help!

[BlueParrot]

Thanks. I've found a fix by using another multimeter that has a USB connection. So now I'm using both GPIB and USB, one for each device. This means that there is no bus conflict.

Philip