It seems to me as if the AT-GPIB/TNT(PnP) is not actually at PAD 0. When you perform the ibcmd �@!x�, if the board were at PAD 0, then TACS should be set in the status. You are recieving an EADR error on the ibwrt because the board is not addressed to talk. I know that the document states that the PAD is at 0, but it appears that this may not be the case. One way to guarantee this is to call ibpad(ud,0).
Craig A
National Instruments Engineer