This file describes in text (top portion) and in matlab code (bottom
portion) the part of /home/adcp/cruise_cfg.m__ most likely to 
need editing for a new setup

--------------------------------------------


The part of cruise_cfg.m__ one usually has to change is the 'rules':
These 'rules' decide:
      - what fields do we need?
      - what instrumets will we get them from?

When you fill these out, keep in mind
(1) "best.rules" is a cell array with one text entry per field
     Those fields are usually {'gps', 'heading', 'pitch', 'roll'};
(2) Every text entry in "best.rules" needs an instrument and a suffix.
    Instrument NMEA messages are expected to have checksums
    (the one exception is gyro HDT or HDG messages -- see below)
(3) each instrument name ('gpsnav', 'ashtech', etc) is specified in
    sensor_cfg.py and corresponds to the directory name in which data
    are logged.  The message name refers to the NMEA string that is
    parsed (eg. GPGGA, PASHR,...).  These each get a different suffix.
       suffix   instrument string        
       ------   ------------------
       gps       ??GGA message (e.g., INGGA or GPGGA)
       hdg       HEHRC or HEHDT messages from serial gyro 
       hnc       HEHRC or HEHDT gyro heading, NO CHECKSUM
       adu       PASHR,ATT  Ashtech
       pmv       POSMV $PASHR  
       rdi       PRDID  
       sea       combination if PSXN,20 and PSXN,23 attitude from seapath
       gps_sea   same as gps, but with PSXN,20 quality (seapath)


NOTE: The use of 'best' for heading is somewhat unfortunate.
      It should really say 'most reliable'.  We choose a serial
      gyro entry for this field, and correct the heading afterwards.


The part of cruise_cfg.m__ to edit is the usually limited to the following:

%%%--- begin snippet ---%%%

best.rules = {'gps', 'heading', 'pitch', 'roll'};

%%                   instrument        message
%%                   ---------        --------
best.gps_rule  =    {'gpsnav',         'gps'};  %% usually pcode or other gps 
best.heading_rule = {'gyro',           'hdg'};  %% "best" = "most reliable"
best.pitch_rule =   {'ashtech',        'adu'};  %% recorded but not implemented
best.roll_rule  =   {'ashtech',        'adu'};  %% recorded but not implemented

%%%--- end snippet ---%%%


The following are examples for a variety of circumstances:


%% ================  positions: best.gps_rule =====================
% choose one

best.gps_rule  =    {'gpsnav',       'gps'};  % position from 'pcode'
best.gps_rule  =    {'ashtech',      'gps'};  % position from 'ashtech'
best.gps_rule  =    {'posmv',        'gps'};  % position from 'posmv'
best.gps_rule  =    {'seapath',      'gps'};  % position from 'seapath'
best.gps_rule  =    {'seapath',  'gps_sea'};  % position from 'seapath'


%% ===========  original reliable heading: best.heading_rule ============
% choose one

best.heading_rule = {'gyro',           'hdg'}; %  gyro WITH checksum messages
best.heading_rule = {'gyro',           'hnc'}; %  gyro WITHOUT checksum messages
                                                

%% ================  attitude: best.pitch_rule, best.roll_rule ===============
% choose a pair, if needed
% These are recorded for informational purposes in the database,
%    but are not implemented in the transformation


best.pitch_rule =   {'ashtech',        'adu'}; 
best.roll_rule  =   {'ashtech',        'adu'}; 

best.pitch_rule =   {'posmv',          'pmv'}; 
best.roll_rule  =   {'posmv',          'pmv'}; 

best.pitch_rule =   {'seapath',        'sea'}; 
best.roll_rule  =   {'seapath',        'sea'}; 

% occasionally there will be a ship that has a heading-only output
% from an optical gyro (for instance) as its only 'more accurate'
% heading source.  If the instrument is reliable, go ahead and
% use that as the primary heading, and specify that there will
% be no heading correction.  If there is no pitch or roll info
% from the attitude sensor, specify that no pitch or roll are expected:

best.rules = {'gps', 'heading'};