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           Trimble R-Utilities v2.35 -- README35.TXT
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SUMMARY:

   This file provides information about the v2.35 release of the
   R-Utilities software.  The main features of this release are:

       - Behavior across the 1 January 2000 boundary has been
         improved.

       - A Linux version of the R-Utilities is included.

       - The HP-UX and SPARC Solaris versions no longer use host
         ID based security.



RELEASE ITEMS:

    This section enumerates enhancements and issues related to
    this release.

	- The rfile time ordered directory (-t option) now works
	  properly when displaying a directory which includes
	  files both before and after 1 January 2000.

	- The rsession program has been modified to enable
	  programming across year boundaries.  A year may now
	  be specified (-Ydd-mm-yy).  In addition, when only
	  the month and day are specified (-Ydd-mm) and the
	  date in the current year is over 30 days earlier
	  than the current time on the host computer, the
	  session is programmed to take place during the next
	  year.

        - A new option "--rtscts" is now supported which
	  disables the use of hardware flow control.  This is
	  useful when operating with a direct cable connection
	  to a receiver.

	- An new option "--dropdtr" is provided to un-assert the
	  DTR line upon program termination.  This may be useful
	  where the DTR line enables a communications link
	  function, for example, RF transmission by a radio modem.



GENERAL ITEMS:

    This section describes some general issues related to the
    use of the R-Utilities software.

        - These utilities operate with 4000SSE/SSi receivers.
	  The REMOTE DOWNLOAD option must be installed in the
	  receiver to enable operation of the R-Utilities.
	  
	  Note that the REMOTE DOWNLOAD option also enables
	  some other features in recent releases of the 4000
	  series firmware.  These include support of a modem
	  setup string (MODEM SETUP item under the MODIFY
	  menu) and support for MET data collection (MET/TILT
	  INTERFACE under the CONTROL menu).

	  The modem setup string is sent to the modem attached
	  to the receiver every 5 minutes when there is no
	  active connection.  Sending such a string is useful
	  in some systems for ensuring that the modem serial
	  interface is operating with the same configuration
	  as the receiver.  Example strings include "AT" or
	  "ATQ1E0".  Whether to send a string and what string
	  to send will be a function of the modem model and
	  configuration.
	  
	  The MET/TILT interface enables collection of data
	  from any device that supports the Paroscientific MET3
	  style of serial interface.  A NULL terminated ASCII
	  string with the following format is logged in a Type
	  16 Subtype 254 record whenever I/O is performed with
	  the MET device.

	      TimeTag|QueryStringSent|ResponseStringReceived

	- For continuous monitoring applications it is often
	  useful to be able to log shorter duration files but
	  be able to concatenate them into larger files for
	  geodetic processing.  However, when normal sessions
	  are programmed, cycle slips are flagged at the start
	  of each session, and there is a brief gap of data
	  since sessions are scheduled with a resolution of
	  one minute.  The 4000 supports a "continuous logging"
	  mode of operation where files of a specified duration
	  are logged continuously.  There are no slips or data
	  gaps between files.  When memory fills, the oldest
	  files are deleted and logging continues to operate.
	  This mode may be enabled from the front panel (see
	  the MORE button under the QUICKSTART controls) or
	  it may be started by using the following form of the
	  R-Utilities rsurvey command, where INTERVAL is the
	  duration in minutes of the logs to be filed.
	  
	      rsurvey ... -q -kINTERVAL

          See the attached section titled "CONTINUOUS DATA
	  LOGGING ON THE 4000 GPS RECEIVERS" for a detailed
	  description of this mode of operation.  See the
	  rsurvey command usage for information about other
	  QUICKSTART options that may be specified in the
	  command line.

	  Note that the naming of files created when using
	  continuous logging is a bit cryptic.  Since the
	  sort order is the same as the time order of the
	  sessions, creating a time ordered list of files
	  is simply a matter of sorting the file names.
	  Final naming may be accomplished by using the
	  rdatname program to determine the date/time values 
	  for converted DAT files.

        - When configuring an HP-UX system for operation, make
	  sure the device file minor number configures the
	  "receive FIFO trigger level" and "transmit limit"
	  parameters to a value higher than 1 byte.  (When set
	  to 1 byte, modem connections can fail or remote links
	  can be shut down after a short period.) As an
	  example, on a Series 700 machine, configuring the
	  internal serial port device with a minor number of
	  0x00a000 sets these thresholds both to 8 bytes.  See
	  "man termios" for more information.



INSTALLATION:

    Make sure to back up any previous versions of the R-Utilities
    software before installing this update.  The following files 
    are included in this release.

        All platforms:
	    rconn, rcontrol, rdatname, rdisconn, rfile, rreset,
	    rsession, rstation, rstatus, rsurvey, runpkr00

        HP-UX and SPARC Solaris:
	    xpanel, Xpanel

    The MS-DOS release is provided as a ZIP file (msdos235.zip).
    Use pkunzip, WinZIP, or any Unix version of unzip to extract
    the files from this archive.

    All other versions are provided as tar archives (linux235.tar,
    sparc235.tar, and hpux235.tar).  To extract the files from
    these archives, execute a command like the following example
    for Linux:

	$ tar xvf linux235.tar



--------------------------------------------------------------- 
       CONTINUOUS DATA LOGGING ON THE 4000 GPS RECEIVERS
--------------------------------------------------------------- 

Continuous Data Logging is the name of a mode of collecting
survey data where data measurements are continuously collected
for a very long time and stored in a sequence of automatically
generated files.  The process is designed to allow users to
collect data, essentially forever without any user interaction.

When the receiver is in the Continuous Logging mode, the data is
broken up into files with a fixed duration.  When a file
reaches its full duration, it is closed off and a further data
is directed to a new file.  When the 4000SSx data logging memory
becomes completely filled, the oldest files are automatically
deleted.  Thus, the receiver always contains a set of the most
recent files.

While new data is being collected, the rfile program can be
used to download the older files from the 4000SSx to a computer
for processing.  Thus, the amount of data that can be collected
is limited only by the amount of storage on the computer system.


STARTING AND STOPPING CONTINUOUS LOGGING

Continuous surveying is activated on the receiver as a form of
Quickstart Survey.  This can be done from the front-panel
keyboard or by using the rsurvey utility.  From the keyboard,
the Continuous mode is controlled using the sequence LOG DATA -
"MORE" - "SETUP SURVEY CONTROLS" - "MODIFY QUICKSTART CONTROLS".
If the top softkey is labeled "MORE", then pressing it leads to
the control screen.  The mode can be turned ON or OFF and the
DURATION of the files, in minutes, can be set to any of the
following: 

	1, 2, 5, 10, 15, 30, 60, 120, 240	

Firmware v7.16 and later added any whole hour size up to 24 hours.

If the mode is turned on, starting a Quickstart survey will
initiate the Continuous Logging.  The various Quickstart Survey
controls, Elevation Mask, etc., will all be applied to all of the
Continuous Logging sessions.

>From the remote control interface, Continuous Logging is available
using the -K option to the rsurvey program.  See the Quickstart
usage information for rsurvey for more information on parameters.

Continuous logging is halted by using the normal means for stopping
a Quickstart Survey.  From the keyboard, use LOG DATA - "END SURVEY".
>From an external computer use "rsurvey -E".


FILE NAMES

When Continuous Logging is active, data files will automatically be
created containing the survey data.  Unique filenames will be 
generated that depend on the receiver serial number and the time 
at which the file is created.  The first four characters will be
the serial number.  The last four characters will be a sequence
of letter and numbers that is derived algorithmically from the
count of minutes within the current year at the time the file is
created.  The first file in the year will be of the form 1234-A000,
where 1234 is the serial number and A000 is the encoded time.
The time portions are guaranteed to match between files collected
at the same time on different receivers, and the character string
will not repeat within a year.  Furthermore, the time portions are
guaranteed to sort into time order based on ASCII lexical order.


STORAGE CAPACITY

Of primary concern with continuous logging is the amount of time
that can elapse without any downloads before older files will be
deleted.  This is dependent on the amount of logging memory in
the receiver, the type of survey data being stored, the data
storage interval, the number of satellites being tracked, etc.
Given the number of variables, it is not possible to give a
fixed number of hours of capacity versus the number of megabytes
of storage.  A rough estimate for a particular receiver can be
obtained from the SURVEY DATA FILES control screen, when all
files have been deleted.  The value shown is for the indicated
conditions (for example, 6SVs,1.0sec) and takes into account
whether the receiver has dual frequency capability, etc.

Capacity can also be limited by the size of the directory in the
data logging memory, especially for short duration files.  For
receivers with FLASH EPROM based logging memory, there is a
limit of 504 files in the data logging directory.  Thus with one
minute files, a maximum of 504 minutes of data can be collected,
regardless of other conditions.  This limitation is summarized
in the following table:

	    TIME TO COLLECT 504 DATA FILES
	    -------------------------------
	    duration	    Maximum storage
	    --------        ---------------
	     1 min.		 0.35 days
	     2 			 0.70 
	     5 			 1.75
	    10 			 3.50
	    15			 5.25
	    30			10.50 

Beyond 30 minutes the limit would be very hard to reach with 
reasonable data logging rates, and the normal limiting factors
would dominate.


USING CONTINUOUS LOGGING FILES

Each data file collected in Continuous Logging mode contains a full
set of data records which can be processed as if it were a normal
"single-shot" survey.  Besides the data records, the normal ephemeris 
records, message records, etc., are all present.  The data files
can be downloaded in the usual manner and processed normally.

If the rfile utility is used to download the files, then sequential
.R00 files will be created.  The preferred method for concatenating
these files is to use runpkr00 with the "@file" option where "file"
contains a list of .R00 files to be processed.  A single .DAT file is
created from multiple (sequential) .R00 files.  It is also possible
to convert the files individually and concatenate the .DAT files
after conversion, but this results in some minor inconsistencies in
the .DAT file header records and inefficiencies.  In either case,
the large .DAT file would appear as if it were a single large survey.
