: XPACK ( blkno -- )
    BLK@
    BLK( 0x2e RAM+ ! ( boot ptr )
    ['] (boot<) 0x08 RAM+ ! ( C<* override )
    BEGIN
        WORD
        0x2e RAM+ @ BLK( 1024 + < IF
            DUP LIT< ( S= IF
                DROP [COMPILE] (
            ELSE
                SCPY 0x20 C,
            THEN 0 ( loop again )
        ELSE 1 ( stop looping ) THEN
    UNTIL
    0 0x08 RAM+ !
;