FM300 Network Server User'

FM300 Network Server
User’s Manual
March 2005
MEDA, Inc.
Macintyre Electronic Design Associates, Inc.
43676 Trade Center Place, Suite 145
Dulles, VA 20166
FM300 Network Server User’s Manual
Disclaimer of Warranty
FM300 Network Server
NO WARRANTIES OR CONDITIONS: Macintyre Electronic Design Associates, Inc.
disclaims any warranty or condition for the software product. The software product and
any related documentation are provided “as is” without warranty or conditions of any
kind, either expressed or implied, including, without limitation, the implied warranties of
merchantability, fitness for a particular purpose, or noninfringement. The entire risk
arising out of use or performance of the software product remains with you.
LIMITATION OF LIABILITY: To the maximum extent permitted by applicable law, in no
event shall Macintyre Electronic Design Associates, Inc. be liable for any special,
incidental, or consequential damages whatsoever (including without limitation, damages
for loss of business profits, business interruption, loss of business information, or any
other pecuniary loss), arising out of the use of or inability to use the software product or
the provision of or failure to provide support services, even if Macintyre Electronic
Design Associates, Inc. has been advised of the possibility of such damages. In any
case, Macintyre Electronic Design Associates, Inc.’s liability shall be limited to the
greater of the amount actually paid by you for the software product or US $5.00.
Because some states and jurisdictions do not allow the exclusion or limitation of liability,
the above limitation may not apply to you.
Microsoft, Windows and Windows NT are trademarks of Microsoft Corp.
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Table of Contents
Page
Overview ...................................................................................................................................................... 1
Starting the Server ...................................................................................................................................... 2
Server Property Page ................................................................................................................................ 3
FM300 Property Page ............................................................................................................................... 4
Logging Property Page .............................................................................................................................. 4
Data Log File Name ..............................................................................................................................................5
Event Log File Name .............................................................................................................................................5
Advanced Property Page .......................................................................................................................... 6
Single Client With Full Control .............................................................................................................................6
Multiple Clients with Data Requests Only ............................................................................................................6
Server Commands ...................................................................................................................................... 6
Informational .............................................................................................................................................. 7
Data Retrieval ............................................................................................................................................ 7
FM300 Specific .......................................................................................................................................... 9
Buffer Mode Value .............................................................................................................................................. 10
Logging .................................................................................................................................................... 11
Testing the Server ..................................................................................................................................... 11
Error Messages ......................................................................................................................................... 13
Data Log File Format ................................................................................................................................ 14
Data Sample Format ................................................................................................................................. 14
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FM300 Network Server User’s Manual
Overview
The FM300 Network Server is a computer program that can be used to log data from a locally
connected FVM400 to a disk file, make the data available to remote clients over the internet and
allow a remote client to control the local FVM400 over the internet.
The FM300 Network Server has two modes of operation: single client and multiple clients. In
single client mode, one client at a time has complete control of the FVM400. In the multiple
clients’ mode, many remote clients can retrieve data but they cannot change the FVM400 settings.
The owner of the FM300 Network Server host determines the operating mode of the server.
The client for the FM300 Network Server can be a Telnet connection or a custom designed client
program. The FM300 Front Panel program that comes with every FVM400 vector magnetometer
is a client for the FM300 Network Server. With the FM300 Front Panel program the user can:
•
Download the most recent remote FVM400 reading.
•
Download the most recent readings stored in a buffer by the FM300 Network Server.
•
Download data files logged by the FM300 Network Server.
•
Strip chart the remote FVM400 readings as they are being acquired.
Click on the Help button in the FM300 Front Panel screen or see the FM300 Front Panel User’s
Manual for more information about using these features.
In the single client mode, the user has an expanded set of commands that can be used to
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•
Get/set the remote FVM400 measurement coordinate system.
•
Get/set the component displayed on the remote FVM400 screen.
•
Get/set the measurement mode (absolute or relative) of the component displayed on the
remote FVM400 screen.
•
Download the 525 samples stored in the remote FVM400 internal buffer.
•
Start a remote FVM400 7.5 second Snapshot recording.
•
Start a remote FVM400 30 second Record recording.
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Starting the Server
To start the server,
1.
Connect the local FVM400 to one of the PC’s RS232 (COM) ports.
2.
Turn the local FVM400 on and press the Remote key.
3.
Click on the Start button in the status bar at the bottom of the Windows 9x/ME or Windows
NT/2000/XP screen.
4.
Select Programs from the Start menu and then select the FM300 Front Panel program group.
5.
In the program group list, double click on the FM300 Network Server entry to start the
program.
A dialog box with four (4) tabs appears on the screen when the FM300 Network Server starts up.
Each tab corresponds to a group of properties that the user can set before the server begins
operation. These properties determine the operating mode of the server. The following sections
describe how to set the server configuration.
Once the server configuration is set, click on the OK button to activate the server. A window will
appear, such as the one below, which informs the user that the server has been started and lists the
data and log file paths.
Each entry in the status window begins with the Greenwich Mean Time (GMT) and date of the
event being recorded. When a client connects to the server or issues a command, the time and
date stamp will be followed by the client’s IP address and the command requested or a message
indicating some action that was taken that was associated with the client (e.g., the client was
connected or disconnected).
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Server Property Page
The Server property page shown below is the first one that appears on the screen after the server is
started.
In the Port box enter the network port address or accept the default value. The base port address
is 20,000. The port number entered into the Port box is added to the base port address. Normally,
the default value is accepted unless more than one server is active on the host computer. In that
case, each active server must have a unique port number.
In the ID box enter anything that will identify the server to a client. In the example above, the id
is the IP address of the host computer. The information in this box is sent to a client in response to
the ID command.
In the Location boxes enter information that will tell the client the location of the server. The
Longitude and Latitude titles for the boxes are only to suggest what location information would
be useful. Other descriptive information could be placed in these boxes. When the client sends
the LOCATION command to the server, the server responds by sending this information to the
client.
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FM300 Property Page
Use the FM300 property page shown below to specify the serial communications port and
measurement coordinates of the local FVM400.
To select the communications port for the local FVM400, click on the down arrow to the right of
the control in the Com Port group. A list of available COM ports will be displayed. Select the
COM port to which the FVM400 is connected.
To select the measurement coordinate system for the local FVM400, click in the appropriate radio
button in the Coordinates group.
Enter the serial number and the calibration due date of the local FVM400 in the edit control boxes
(optional).
Logging Property Page
Use the Logging property page shown below to specify the data and event logging properties and
the sample interval (if data logging).
To enable data logging, click in the Data Log check box, specify a sample interval and either
enter a base path for the data files or accept the default path. The minimum sample interval is 0.25
seconds.
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To enable event logging, click in the Event Log check box and enter a base path for the event log
file or accept the default path.
The default path for the data and event log files is the same directory in which the FM300
Network Server program resides. You are free to enter any valid path. Do not include a file name.
The data and event logs have specific file names that cannot be altered by the user.
Data Log File Name
The data log file name is based on the date and hour in which the file was created as shown below:
YYMMDDHHmm.fmd
where YY is the two digit number for the year, MM is the two digit number for the month (1 to
12), DD is the two digit number for the day (1 to 31), HH is the two digit number for the hour (1
to 24) and mm is the two digit number for the minute (1 to 60). The suffix fmd indicates that it is
an FM300 Network Server data file.
The data log file stores up to 3600 samples and can span many hours or days depending on the
sample interval. See the Data Log File Format section for detailed information about the structure
of the data log file.
Data can be lost if the server is started, stopped and restarted within the same hour. When the
server is restarted, it will overwrite the data file created when the server was started earlier in the
hour. To prevent data loss, rename the existing data file before restarting the server.
Event Log File Name
The event log file name is shown below:
EVENTLOG.0DD
where DD is the day of the month. The event log records the date and time of each event that
occurs while the server is active. Events recorded in the log file include commands received from
clients, creation of new data log files and error messages. If the server is stopped and restarted
during the same day, the existing event log file is not overwritten; new events are appended to the
events recorded in the existing event log.
Below are example entries in the event log file.
Sun,
Sun,
Sun,
Sun,
Sun,
Sun,
Sun,
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02
02
02
02
02
02
02
Jan,
Jan,
Jan,
Jan,
Jan,
Jan,
Jan,
2000
2000
2000
2000
2000
2000
2000
18:33:49
17:35:57
17:40:19
17:40:22
17:40:39
17:40:39
17:40:44
GMT
GMT
GMT
GMT
GMT
GMT
GMT
created new
started the
38.243.64.5
38.243.64.5
38.243.64.5
38.243.64.5
38.243.64.5
5
event log file: C:\temp\eventlog.002
server
connected
get buffer
connection lost
connected
get buffer
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Advanced Property Page
Use the Advanced property page shown below to specify single or multiple client server
operation.
To select the mode of operation, click in the appropriate radio button.
Single Client With Full Control
In this mode of server operation, only one remote client at a time can connect to the server.
Connection requests from other clients will be denied until the current client disconnects.
The connected client has an expanded set of commands available to control the remote FVM400.
These additional commands allow the client to change the measurement coordinate system, set the
measurement mode (absolute or relative) of each component, start a Snapshot recording, start a
Record recording and download data from the internal FVM400 buffer. See the Server
Commands section for a detailed description and the syntax of each command.
Multiple Clients with Data Requests Only
In this mode of server operation, the client can only download data (sample, buffer and files).
Many clients can be connected to the server at the same time. Client requests are processed in the
order in which they are received.
Server Commands
The FM300 Network Server responds to commands that are sent from a remote client over a
network using the TCP/IP protocol. These commands are divided into four functional groups:
Informational: Retrieve information about the server location and local FVM400.
Data retrieval: Retrieve data collected and logged by the server.
FVM400 control: Control the FVM400 operating state and retrieve data stored in the FVM400
internal buffer.
Logging: Determine the current logging state and turn it on or off.
The FVM400 control commands and the logging on/off commands are only available in single
client mode.
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If a command is successful, the server will respond with 200 OK on the first line followed by
additional lines that provide the requested information or data. A blank line indicates the end of
the transmission.
If a command was unsuccessful, the server will respond with a three digit number followed by
text indicating what caused the command failure. A blank line indicates the end of the
transmission. See the Error Messages section for a listing of the messages that can be sent by the
server to the client.
To disconnect from the server in a graceful manner, the client should send the DISCONNECT
command.
Informational
Use the informational commands to determine the
•
Name and location of the server.
•
Serial number and calibration due date of the local FVM400.
•
Measurement coordinate system which applies to the data being collected by the server.
The table below lists the command syntax and the response from the server if the command is
successful.
Command
Description
Response
ID
Returns the name of the server.
200 OK
id <name>
LOCATION
Returns the longitude and latitude of the
server.
200 OK
location <longitude>,<latitude>
SN
Returns the serial number of the FVM400.
200 OK
sn <serial number>
CALDUE
Returns the calibration due date.
200 OK
caldue <calibration due date>
COORD
Returns the measurement coordinate system.
A value of zero (0) indicates the rectangular
coordinate system and one (1) indicates the
polar coordinate system.
200 OK
coord <value>
The item between the angle brackets <> is an ASCII character string. All lines are terminated in a
carriage return (ASCII code 13) linefeed (ASCII code 10) pair. A blank line that contains only a
carriage return/linefeed pair signals the completion of the command and the completion of the
response. All commands are case insensitive, therefore ID and id are equivalent.
Data Retrieval
Use the data retrieval commands to
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•
Get a single sample.
•
Download the most recent samples saved by the server in a buffer.
•
Download a data file logged by the server.
•
Download a directory of data files.
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•
Determine and change the sample interval of the server.
•
Determine and change the client’s broadcast status.
The table below lists the command syntax and the response from the server if the command is
successful. For a description of the sample data format returned by the GET commands, see the
Data Sample Format section.
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Command
Description
Response
GET SAMPLE
Returns the latest measured
sample. If the server is not data
logging, an error message is
returned. A coord value of zero
(0) indicates the rectangular
coordinate system and one (1)
indicates the polar coordinate
system.
200 OK
sample
coord <value>
<time>,<X>,<Y>,<Z>
GET BUFFER
Returns the data stored in the
server buffer. If the server is not
data logging, an error message is
returned.
200 OK
buffer
coord <value>
interval <sample interval>
samples <number of samples>
<time>,<X>,<Y>,<Z>
.
.
<time>,<X>,<Y>,<Z>
GET FILE <file name>
Downloads data from a data file.
The file name must be a valid
one. Use the DIR command to
get a list of data files before using
this command.
200 OK
file
name <file name>
length <length in bytes>
sn <serial number>
longitude <longitude>
latitude <latitude>
coord <value>
<time>,<X>,<Y>,<Z>
.
.
<time>,<X>,<Y>,<Z>
DIR
Downloads a directory of data
files including each file name,
length and creation date and time.
200 OK
dir
<file name>/<length>/<created>
.
.
<file name>/<length>/<created>
DIR <file name>
Downloads information about the
specified file or set of files.
Wildcards such as ‘?’ and ‘*’ are
allowed in the file name.
200 OK
dir
<file name>/<length>/<created>
.
.
<file name>/<length>/<created>
SI
Returns the sample interval in
seconds. If the server is not data
logging, a sample interval of zero
(0) is returned.
200 OK
interval <interval>
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SI <interval>
Sets the sample interval in
seconds. This command is only
available in single client mode. If
the server is not data logging, an
error message is returned.
200 OK
interval <interval>
BROADCAST
Returns the client broadcast state.
A client can request that the
server send it data each time a
new sample is taken. Use this
command to determine if
broadcasting is ON or OFF. If
the server is not data logging, an
error message is returned.
200 OK
broadcast <state>
BROADCAST <state>
Sets the broadcast state. If the
state is set to ON, the server will
send the client a new sample each
sample interval. If the server is
not data logging, an error
message is returned.
200 OK
The item between the angle brackets <> is an ASCII character string. All lines are terminated in a
carriage return (ASCII code 13) linefeed (ASCII code 10) pair. A blank line that contains only a
carriage return/linefeed pair signals the completion of the command and the completion of the
response. The commands are not case sensitive, therefore, BROADCAST and broadcast are
equivalent.
FVM400 Specific
Use the FVM400 specific commands to
•
Get or set the FVM400 measurement coordinate system.
•
Get or set the FVM400 active component.
•
Get or set the mode of the FVM400 active component.
•
Download the data from the FVM400 internal buffer.
•
Start an FVM400 7.5 second Snapshot recording.
•
Start an FVM400 30 second Record recording.
These commands are only available to the client in single client mode. The table below lists the
command syntax and the response from the server if the command is successful.
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Command
Description
Response
DEV GET COORD
Retrieve the measurement coordinate
system. A value of zero (0) indicates
the rectangular coordinate system. A
value of one (1) indicates the polar
coordinate system.
200 OK
dev coord <value>
DEV SET COORD <value>
Sets the FVM400 measurement
coordinate system. The command
above describes the correspondence
between value and the coordinate
system
200 OK
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DEV GET COMP
The returned value indicates the
active component of the FVM400.
For rectangular components, values
of 0, 1 and 2 correspond to X, Y and
Z. For polar components, values of 0,
1 and 2 correspond to R, D and I.
200 OK
dev comp <value>
DEV SET COMP <value>
Sets the active component. The
command above describes the
correspondence between value and
the active component.
200 OK
DEV GET MODE
The returned value indicates the
measurement mode of the active
component. A value of zero (0)
indicates the absolute mode while a
value of one (1) indicates the relative
mode.
200 OK
dev mode <value>
DEV SET MODE <value>
Sets the measurement mode of the
active component. The command
above describes the correspondence
between the value and the component
measurement mode.
200 OK
DEV GET BUFFER
Downloads the contents of the
FVM400 internal buffer. A type
value of zero (0) indicates Snapshot
data, one (1) indicates Record data
and two (2) indicates manual data.
The coord value was described under
the DEV GET COORD command.
The mode value format is described
below.
200 OK
type <value>
coord <value>
mode <value>
0 <X> <Y> <Z>
1 <X> <Y> <Z>
.
.
524 <X> <Y> <Z>
DEV START SNAPSHOT
Starts a 7.5 second FVM400
recording.
200 OK
DEV START RECORD
Starts a 30 second FVM400
recording.
200 OK
The item between the angle brackets <> is an ASCII character string. All lines are terminated in a
carriage return (ASCII code 13) linefeed (ASCII code 10) pair. A blank line that contains only a
carriage return/linefeed pair signals the completion of the command and the completion of the
response. The commands are not case sensitive, therefore, DEV GET MODE and dev get mode
are equivalent.
Buffer Mode Value
The buffer mode value returned by the DEV GET BUFFER command, when converted to an
eight bit binary representation, indicates the measurement modes of the components stored in the
FVM400 buffer. Bits zero (0), one (1) and two (2) indicate the measurement mode of the X, Y
and Z components, respectively. Bits four (4), five (5) and six (6) indicate the measurement mode
of the R, D and I components, respectively. Bit numbering is from least to most significant. A
zero (0) in a bit position means the corresponding component is an absolute measurement while a
one (1) indicates a relative measurement. The coord value returned by the DEV GET BUFFER
determines which bits are significant. For more information, refer to the FVM400 Instruction
Manual.
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Logging
The logging commands can be used to
•
determine whether or not the server is logging data,
•
turn logging on or off (only available in single client mode).
The table below lists the command syntax and the response from the server if the command is
successful.
Command
Description
Response
LOG
Returns the logging state, either ON or
OFF.
200 OK
log <state>
LOG <state>
Sets the logging state to ON or OFF.
200 OK
The item between the angle brackets <> is an ASCII character string. All lines are terminated in a
carriage return (ASCII code 13) linefeed (ASCII code 10) pair. A blank line that contains only a
carriage return/linefeed pair signals the completion of the command and the completion of the
response. The commands are not case sensitive, therefore, LOG and log are equivalent.
Testing the Server
You can test the FM300 Network Server using the Telnet program that comes with Windows
95/98 and Windows NT. Use the Find program on the Start menu to find the Telnet program by
searching for the file telnet.exe.
Your computer does not need to be connected to a network but must be network enabled and have
TCP/IP as one of the installed network protocols. Double click on the Network icon in the
Control Panel group and see if TCP/IP is an installed protocol. If it is not, click on the Add button
in the Configuration properties page (Windows 9x/ME) or Protocol properties page (Windows NT
4.0/2000/XP) and follow the on-screen instructions. See your Windows Help for information on
making your computer network ready. If you can connect to the internet through a modem or
local area network (LAN), you are network enabled.
To test the FM300 Network Server
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1.
Start the server (see the Starting the Server section) and use the default port number.
2.
Run the Telnet program and select Remote System from the Connect menu.
3.
In the Connect dialog box (see below), enter the IP address of the server and its port number.
4.
Enter 127.0.0.1 in the Host Name box and 20000 in the Port box. 127.0.0.1 is the loop back
IP address for the local host (your computer), and 20000 is the base port number for the
FM300 Network Server.
5.
Click on the Connect button.
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The Connect dialog box will disappear and you will now be connected to the server. The
following message will be displayed:
200 OK Welcome to the FM300 Net Server.
To see what commands you are sending to the server, select Preferences from the Terminal menu
and, in the dialog box, check Local Echo.
To send a command to the server, enter the command and press the Enter key twice. The second
Enter key signals the server that the command message is complete. The server will acknowledge
receipt of the command with 200 OK, if the command executed correctly, or an error message.
The lines following the acknowledge line will contain the requested information. A blank line
indicates completion of the response from the server. See the section on Server Commands for a
complete list of the server commands and responses.
The figure below is an example of a typical Telnet session.
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Error Messages
The following table lists all the error messages that can be returned in response to a server
command.
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Message
Description
200 OK
The command was received and is being
processed. The lines following this one will
include the requested data or information. See
the specific command description to
determine what additional lines are returned,
if any.
200 OK Welcome to the FM300
Net Server
The greeting that the client sees when the
server is first connected to the client.
400 syntax error
Syntax error in the command sent to the
server.
401 error in parameter
The command token was correct, but an
associated parameter was either not included
or had an out-of-bounds value.
403 command not available
The command token was correct, but the
command is either not implemented or the
server is not in single client mode and,
therefore, the command is not allowed.
404 not found
The requested data file was not found.
501 connection denied
The server is in single client mode and a client
is already connected.
503 the server has shut down
The server has shut down for some reason.
504 internal server error
An internal error in the program has prevented
the server from carrying out the request.
505 FM300 not responding
The local FVM400 is not responding to server
commands, therefore, the requested action
cannot be carried out.
506 data logging
The server is in the data-logging mode and
cannot respond to commands that alter the
FVM400 state.
507 could not create data file
This message is returned when the server is in
single client mode if a data log file could not
be created in response to the LOG ON
command.
508 not logging. Buffer is empty.
Returned in response to a GET SAMPLE or
GET BUFFER command if the server is not
logging.
509 not logging. No broadcast data.
Returned in response to a BROADCAST ON
command if the server is not data logging.
Data can be broadcast to the client only when
the server is logging.
550 file not found
The server could not find the requested data
file.
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553 file name not allowed
The requested file name was not a valid data
file name. See the Logging Property Page for
a description of valid data file names.
Data Log File Format
The data log file is a text file that contains a header which provides information about the data,
followed by the sample points. Shown below is an example of the file format.
sn em1234
longitude 77d 53’ west
latitude 38d 5’ north
coord 1
36514.674988, 29992,-13198, 4958
36514.675104, 29992,-13198, 4958
36514.675220, 29993,-13198, 4958
.
.
The number following coord will be zero (0) for rectangular coordinates or one (1) for polar
coordinates. See the Data Sample Format section for a complete explanation of the sample
format.
In the above example, the first column of the sample data gives the time the sample was taken.
Since the coord value is one (1), the coordinate system is polar, and the second column is the total
field value in nanotesla (nT). The third and fourth columns are the declination and inclination
angles, respectively, in hundredths (0.01) of a degree. For example, the first sample was taken on
20 December, 1999 at 16:11:59 GMT. The total field was 29,992 nT, and the declination and
inclination angles were –131.98 degrees and 49.58 degrees, respectively. See the Data Sample
Format section for an explanation of how to convert the time stamp into Greenwich Mean Time
(GMT).
The sample interval in seconds can be determined by subtracting the first two time values and
multiplying by 86,400. In the above example, the sample interval is
(36514.675104 – 36514.674988) x 86,400 = 10.02 seconds.
Data Sample Format
The server returns time stamped samples. The time stamp is a double precision floating point
number. The integer portion of the number represents the whole number of days since midnight,
30 December 1899 Greenwich Mean Time (GMT). The fractional portion of the number
represents the fraction of the day since midnight. For example, noon of 30 December, 1899 is the
first half day since the start of the clock at midnight and is represented as 0.50. The table below
gives several other examples.
Date and Time
Time stamp
30 December 1899, midnight
0.0
01 January 1900, noon
2.50
28 January 1900, 6:00 p.m.
29.75
10 February 1900, 6:00 a.m.
42.25
13 December 1999, midnight
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To convert the time stamp to GMT,
1.
Use the file creation date for the day and year information adjusted to GMT.
2.
Compute the hours, minutes and seconds from midnight using the fractional part of the time
stamp as described below.
To compute the hour, minute and second of the day,
1.
Compute the number of seconds from midnight.
Seconds in Day = (Time Stamp Fraction)*86400
2.
Compute the second of the hour in the day.
Second = (Seconds in Day)%60
3.
Compute the number of minutes in the day.
Minutes in Day = (Seconds in Day)/60
4.
Compute the minute of the hour in the day.
Minute = (Minutes in Day)%60
5.
Compute the hour of the day.
Hour = (Minutes in Day)/60
The % symbol means divide the number on the left by the number on the right and use the
remainder as the answer. Truncate the results of each computation to set the value of the left hand
side of an equation. For example, if the fractional part of the sample time stamp is 0.708773 then
Seconds in day = 0.708774 x 86,400 = 61,238 seconds
Second = 61,238 % 60 = 38 seconds
Minutes in Day = 61238/60 = 1020 minutes
Minute = 1020 % 60 = 0 minutes
Hour = 1020/60 = 17 hours
Therefore, the sample was recorded at 17:00:38 GMT of the day the file was created.
The sample data format depends on the measurement coordinate system. In the rectangular
coordinate system, each component value is a signed six digit integer representing the value of the
component in nanotesla (nT). In the polar coordinate system, the magnitude of the field is a
positive six digit integer representing the magnitude of the field in nT. The two angles are signed
five digit numbers representing the values of the angles in hundredths (0.01) of a degree. Both
formats are shown below:
Rectangular coordinates: DDDDD.DDDDDD,SDDDDDD,SDDDDDD,SDDDDDD
Polar coordinates: DDDDD.DDDDDD,DDDDDD,SDDDDD,SDDDD
where D is a digit and S is the sign of the number.
MEDA, Inc.
15
1 Aug, 2002
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