visadev: Connect to 'GPIB0::INTFC'

Hi,

I would like to connect to the GPIB interface board 0 in order to send low-level interface command (send a group execute trigger (GET) to multiple devices simultaneously). However, visadevlist doesnt even list the INTFC (only INSTR are listed), and I cannot connect to 'GPIB0::INTFC'.

Thus, I have to assume, that MATLAB does not support interacting with the interface.

Can someone please proove me wrong? :)

Answer 1

[Shubham]

Hi SpinOrbiter,

Interacting with the GPIB interface board directly to send low-level commands like a Group Execute Trigger (GET) can indeed be challenging in MATLAB, especially if the visadevlist function does not list the GPIB interface as a recognizable device. However, there are ways to work around this limitation. Here are some steps and suggestions to help you achieve your goal:

Verify GPIB Configuration

1. Check GPIB Driver Installation:

• Ensure that the appropriate GPIB drivers are installed on your system. This is often provided by the hardware manufacturer (e.g., National Instruments, Agilent).

2. MATLAB Instrument Control Toolbox:

• Confirm that you have the Instrument Control Toolbox installed. This toolbox provides functions for GPIB communication.

Using MATLAB for GPIB Communication

1. GPIB Interface Object:

• You can create a GPIB object in MATLAB using the gpib function. This object represents the GPIB interface and allows you to communicate with devices connected to it.

% Create a GPIB object
g = gpib('NI', 0, 0); % Replace 'NI' with your vendor's driver name

% Open the connection
fopen(g);

2. Sending Commands:

• To send a Group Execute Trigger (GET), you might need to use the trigger function. However, this function typically triggers a single device. To trigger multiple devices simultaneously, you may need to iterate over each device or use a broadcast address if your setup supports it.

% Send a GET command
trigger(g);

3. Close the Connection:

• Always remember to close the connection after you're done to free system resources.

fclose(g);
delete(g);
clear g;

Troubleshooting

• Device Recognition: Ensure that your GPIB board and connected devices are recognized by your system. Use any vendor-provided utilities to verify communication outside of MATLAB.
• Vendor-Specific Commands: Some GPIB boards may have vendor-specific commands or APIs that allow for more advanced operations, such as sending a GET to multiple devices.

Alternative Solutions

• Using VISA Interface: If direct GPIB access is problematic, consider using a VISA interface, which is often more flexible and may support additional features.
• Third-Party Libraries: Explore third-party libraries or MATLAB Central for custom functions that extend GPIB capabilities.

[SpinOrbiter]

Hi Shubham,

yes, one can open the interface as a gpib object, however, I did not find a way to send for example binary data to it (which would be needed for the general trigger). The trigger(g) function has no effect if the interface is chosen as input, and sending individual tiggers to the instruments kinda defeats the purpose of the GPIB Group Execute Trigger (GET) command ;)

At the moment, I am calling a python function to get the job done, but this is of course a suboptimal solution.