07-27-2011 08:51 PM
I'm using 3 equipments controlled by GPIB interface. In one of the applications, I need to trigger 2 of the equipments to start testing at the same time (by issuing TEST command to both equipments). Is there a way to send a single command to multiple GPIB instruments or 'broadcast'? I know I can sequentially send 2 TEST command to both equipments separately, but this will cause delay to the latter equipment and affects the test result.
07-29-2011 08:34 AM
If you are using the GPIB .NET library you can use the 'Board' object.
Use the 'Write' function to send the same command string to multiple devices in an 'AddressCollection'
if your using LabVIEW, you can use 'SendList'
07-30-2011 12:18 AM
I'm using Labview and unfortunately also VISA to access the GPIB. The reason is that the software needs to support both serial port and GPIB.So, using GPIB allows the software to be used without changes. Is there similar function with VISA?
07-30-2011 04:05 AM
you can use the visa assert trigger function
or simply intermix gpib and visa calls it is not forbidden.
If you use visa you probably need to address the board not the device itself.
Asserts a software or hardware trigger, depending on the interface type. For software triggers, Default (0) is the only valid protocol. For VXI hardware triggers, Default (0) is equivalent to Sync (5). For PXI triggers, PXI: Reserve (6) and PXI: Unreserve (7) are the only valid protocols.
|VISA resource name specifies the resource to be opened. The VISA resource name control also specifies the session and class.|
|protocol is the trigger protocol to use during assertion. This input accepts the following values.
|error in describes error conditions that occur before this node runs. This input provides standard error in functionality.|
|VISA resource name out is a copy of the VISA resource name that VISA functions return.|
|error out contains error information. This output provides standard error out functionality.|
This function sends an IEEE-488.2 software trigger to the addressed device, with the following bus-specific details: