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

© National Instruments Corporation

The following sections describe communication errors you might 
encounter in your application.

Devices adhering to the IEEE 488.2 standard should remain in their current 
state until specific commands are sent across the GPIB to change their 
state. However, some devices require GPIB addressing before any GPIB 
activity. Therefore, you might need to configure your NI-488.2 driver to 
perform repeat addressing if your device does not remain in its currently 
addressed state. You can either reconfigure from your application using 

ibconfig

, or reconfigure using the NI-488.2 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 

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 

.

You should be aware of the data termination method that your device uses. 
By default, your NI-488.2 software is configured to send EOI on writes and 
terminate reads on EOI or a specific byte count. If you send a command 
string to your device and it does not respond, it might not be recognizing 
the end of the command. In that case, you need to send a termination 
message, such as <CR> <LF>, after a write command, as follows:

ibwrt(dev,"COMMAND\x0A\x0D",9);

If you experience other errors in your application, refer to the NI-488.2 
online help. It includes extensive troubleshooting information and the 
answers to frequently asked questions. For instructions on accessing the 
online help, refer to the 

 section in