National Instruments NI-488.2 ユーザーズマニュアル

Several applications require customized configuration of the NI-488.2 
driver. For example, you might want to terminate reads on a special 
end-of-string character, or you might require secondary addressing. In 
these cases, you can either reconfigure from your application using the 

ibconfig

 function or reconfigure using the GPIB Configuration utility. 

National Instruments recommends using 

ibconfig

 to modify the configuration.

If your application uses 

ibconfig

, it works properly regardless of the 

previous configuration. For more information about using 

ibconfig

, 

refer to the description of 

ibconfig

 in the NI-488.2 online help. For 

instructions on accessing the online help, refer to the 

 section in 

If your application fails, but the same calls issued interactively in the 
Interactive Control utility are successful, your program might be issuing 
the NI-488.2 calls too quickly for your device to process and respond to 
them. This problem can also result in corrupted or incomplete data. This is 
only a problem with noncompliant GPIB devices.

A well-behaved IEEE 488 device does not experience timing errors. If your 
device is not well-behaved, you can test for and resolve the timing error by 
single-stepping through your program and inserting finite delays between 
each NI-488.2 call. One way to do this is to have your device communicate 
its status whenever possible. Although this method is not possible with 
many devices, it is usually the best option. Your delays are controlled by the 
device and your application can adjust itself and work independently on 
any platform. Other delay mechanisms can exhibit differing behaviors on 
different platforms and thus might not eliminate timing errors.