I am not quite sure I understand what you are trying to do? You normally select the serial port when you configure the instrument, never from the command line - there are no command line switches apart from the DEBUG environment variable...
Basically if you are creating a new instrument, you define what sort of connection it uses in
instrumentmanager.js (located in
www/js/app/instruments or depending on your build in
oem/radio/www/js/app/instruments) . Each instrument is described in the
supportedInstruments variable, and uses the
connectionsettings key to point to the right connection driver. This way when you create an instrument from the web/app UI, Wizkers knows how to create the right configuration UI elements + connection driver for the instrument.
Does this help ?