I know this is an old thread but here is my 2 cents worth. I just scored a Nano PEB for free with a huge TI lot. I stuck the TI Extended Basic cart in the slot and the Nano in the side slot. Be sure to turn on the Nano first, then the console. If all is well, you should be greeted with the NanoPEB-TI splash screen. Select 2 for Extended Basic, from there it should go right into CFMGR and give you several choices of what to do. I think I chose Catalog to list everything on the CF card. It was that or "List". I'm at work now and don't remember. I took 9 screenshots of what it listed. Quit out and go back to "1" TI Basic. Type "CALL MOUNT (1,X) X= any volume on your card) Say, CALL MOUNT (1,50)
hit enter, quit back out again, this time choose "2" for Extended Basic and if that volume on your card works, something will load.