ERRORLEVELS

    The following errorlevels are returned by BNU (this also
    documents some of the possible errors which can be returned):

         0    No error - operation(s) successful
         1    Status was requested and displayed
         2    A FOSSIL driver other than BNU is present
         3    Incompatible version of BNU is already loaded
         4    Can't modify parameters with ports active
         5    BNU is not yet resident or loaded
         6    Not used
         7    DOS memory allocation error - fatal abort
         8    Invalid command line option
         9    Can't unload - FOSSIL appendages are loaded
         10   System reboot failure
         11   Error enabling or disabling carrier watch
         12   Unable to recapture INT 14H vector
         13   Can't unload if installed from CONFIG.SYS
         14   Maximum combined TX/RX buffer size exceeded
         15   Can't disable/enable diags panel - not loaded
         16   Unable to unload due to interrupt chaining
         17   Problem initialising FOSSIL (with /I)