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

EADR occurs when the GPIB interface is CIC and is not properly 
addressing itself before read and write functions. This error is usually 
associated with board-level functions.

EADR is also returned by the function 

ibgts

 when the shadow-handshake 

feature is requested and the GPIB ATN line is already unasserted. In this 
case, the shadow handshake is not possible and the error is returned to 
notify you of that fact. 

Possible solutions for this error are as follows:

•

Make sure that the GPIB interface is addressed correctly before calling 

ibrd

, 

ibwrt

, 

RcvRespMsg

, or 

SendDataBytes

.

•

Avoid calling 

ibgts

 except immediately after an 

ibcmd

 call. 

(

ibcmd

causes ATN to be asserted.)

EARG results when an invalid argument is passed to a function call. The 
following are some examples:

•

ibtmo

 called with a value not in the range 0 through 17.

•

ibeos

 called with meaningless bits set in the high byte of the second 

parameter.

•

ibpad

 or 

ibsad

 called with invalid addresses.

•

ibppc

 called with invalid parallel poll configurations.

•

A board-level traditional NI-488.2 call made with a valid device 
descriptor, or a device-level traditional NI-488.2 call made with a 
board descriptor.

•

A multi-device NI-488.2 call made with an invalid address.

•

PPollConfig

 called with an invalid data line or sense bit.

Possible solutions for this error are as follows:

•

Make sure that the parameters passed to the NI-488.2 call are valid.

•

Do not use a device descriptor in a board function or vice-versa.