cannot get 6485 into REM mode

If I use VISA, I can put the 6485 into REM mode, but when I write program. 

SendIFC (boardID);
dev = ibdev(boardID, KEITHLEY_PICO, 0,TIMEOUT, EOTMODE, EOSMODE);

ibclr (dev);

6485 does not go into the REM mode. 

I added ibsre without any impact. 

What is the difference here and what do I have to do to get the 6485 into REM mode, without the REM mode, I cannot communicate with it.