## Driver Limitations

### GPIB Driver Limitations

#### Agilent Technologies

The Agilent GPIB driver has these limitations:

• Asynchronous read-and-write operations are not supported. Therefore, Agilent GPIB objects do not support the following toolbox functionality:

• The readasync function
• The async flag for the fprintf and fwrite functions
• BytesAvailableAction and OutputEmptyAction properties
• The End Or Identify (EOI) line is not asserted when the End-Of-String (EOS) character is written to the hardware. Therefore, when the EOSMode property is configured to write and the EOIMode property is configured to on , the EOI line is not asserted when the EOSCharCode property value is written to the hardware.
• All eight bits are used for the EOS comparison. Therefore, the only value supported by the CompareBits property is 8.
• A board index value of 0 is not supported.
• An error is not reported for an invalid primary address. Instead, the read-and-write operations will time out.

#### ICS Electronics

The ICS Electronics GPIB adaptor only works with their USB GPIB controller.

### VISA Driver Limitations

#### Agilent Technologies

The Agilent VISA driver uses all eight bits for the EOS comparison. Therefore, the only value that the CompareBits property supports is 8.

#### National Instruments

The National Instruments VISA driver uses all eight bits for the EOS comparison. Therefore, the only value that the CompareBits property supports is 8.