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-------------------------Monitor------------------------
The Newsletter for PC-Based Data Acquisition and Control
Issue 109 www.windmill.co.uk August 2007
--------------------ISSN 1472-0221----------------------
Welcome to the August issue of Monitor. I hope you
enjoy the newsletter but should you wish to cancel
your subscription you can do so at
http://www.windmill.co.uk/newsletter.html
CONTENTS
========
* Windmill Notes: NMEA Data Acquisition Checklist
* Excel Corner: Formatting All Data Series in a Chart
* DAQ News Roundup
* Data Acquisition Exhibitions
________________________________________________________
________________________________________________________
Windmill Notes: NMEA Data Acquisition Checklist
________________________________________________________
Many instruments use NMEA messages to communicate with
a computer, including GPS receivers, echo sounders
and anemometers.
You can collect data from instruments communicating via
NMEA using the Windmill 6 COMIML software
(http://www.windmill.co.uk/comiml.html), or the free
Windmill 4.3 with LabIML package.
Using Windmill to Collect NMEA Readings
===========================================
The first time you use Windmill you need to tell it:
- how to communicate with your instrument
- which readings you wish to collect.
In future sessions you can immediately start acquiring
data simply by launching the Windmill DDE or Logger
program.
Collecting Data for the First Time
==================================
1. Use an RS232 serial cable to plug your instrument
into one of the PC's COM ports.
2. Use the Windmill 4.3 ConfIML program (or the
Windmill 6 comDebug program) to enter your
instrument's settings.
In ConfIML:
a. Click the Add button.
b. Select LabIML RS232 ASCII Instrument Handler and
click Add.
c. Type a name for your instrument and description.
These can be anything you like. Decide how many
types of measurement you want to collect, and
enter this as the number of channels. For example,
if you were collecting latitude, longitude and depth,
you would need 3 channels. Press OK.
d. Enter your instrument settings. These depend on
your device and its messages, but if in doubt
start with these:
- Reading Protocol: Continuous Flow
- Instrument Idle Time: 0
- Data Persistence: 5000 (assuming you are taking
readings more often than once every 5 seconds)
- Returned Message Length: 100
- Instrument Initialisation String: Leave blank.
3. Use ConfIML to define which data items you want to
collect.
a. Click the Channels button.
b. Enter data collection instructions into the
Parse String box. These tell Windmill which piece
of the data string to extract. A data string will
look something like this...
$WIMWV,151.0,R,001.30,N,A
This contains wind velocity data from a boat
where 151.0 = wind direction, R = wind direction
relative to the boat, 001.30 = speed and N = knots.
- You need to first fix your position in the string.
Click the Reply Parse String box then click the
String Search button. Type $WIMWV, into the
Search For box. This will stop the parser at
the wind direction.
- Click the Extract Until char button and
enter , into the Extract box. In our example
this will obtain the wind direction.
- The Reply Parse String will look like this: \S"$WIMWV,"\E","
- To also extract the wind speed: select channel 1,
search for "R," and extract until ,.
- See your instrument's Manual for details of its
data strings.
- Click OK to close the Channels dialogue and
Settings dialogue
6. Use ConfIML to enter your communication settings.
Click the Comms button. Check your instrument's Manual
for its settings, but if in doubt start with these:
- Baud rate: 4800
- Bits: 8
- Parity: none
Save your settings and leave ConfIML.
7. Run the SetupIML program. Here you can name your
channels, set units, any alarm thresholds and so on.
a. From the Device menu select LabIML.
b. Your data channels will be shown as numbers like
10000, 10001, 10002. Double click a channel.
c. Type name for your channel, eg Windspeed, and
make sure Enable for Input is checked.
d. Save your settings in a *.ims file and
close SetupIML.
8. Run Windmill DDE Panel
a. From the File menu select Load Hardware Setup
and choose the *.ims file you just saved.
b. Connect your channels. You should see your data
in DDE Panel.
c. Proceed similarly for the Logger and Chart programs.
9. Sort out any Problems
If the data shown is not what you expected...
a. Right-click the LabIML icon on the task bar
and select "Debug Options".
b. If the LabIML Debug window says "Parsing Failed",
you need to refine your parsing instructions.
- Close all Windmill programs and IML Device icons.
- In ConfIML select your instrument.
- Press the Settings button.
- Press the Channels button and adjust the
Reply Parse String.
c. If you receive an Error 114 message, this means
that no data is available from your instrument.
This might be caused by:
- too short a persistence time,
- the "returned message length" being shorter
than the actual length of the message,
- a parsing problem,
- a cabling problem
Change the settings in ConfIML or try swapping
the cable. For more trouble-shooting options
see http://www.windmill.co.uk/wiring.html
6. Transfer the data to Excel or a Mapping program
You can use the Windmill Logger program to collect
data, and after collection has finished import it
into Excel or a mapping program. Alternatively, you
can collect data with Excel in real-time by writing
an Excel macro to read data from the
Windmill DDE Panel. For more details see
http://www.windmill.co.uk/excel.html
Further Reading
===============
Interfacing NMEA Instruments to a PC
http://www.windmill.co.uk/nmea.html
Parsing messages from instruments
http://www.windmill.co.uk/parse.html
Connecting a GPS Receiver to a Laptop PC
http://www.windmill.co.uk/gps.html
Interfacing a Garmin GPS Receiver
http://www.windmill.co.uk/garmin.html
Guide to Automatic Sea-Floor Mapping
http://www.windmill.co.uk/seafloormapping.html
________________________________________________________
________________________________________________________
Excel Corner: Formatting All Data Series in a Chart
________________________________________________________
When you have many data series on your chart it is
time-consuming and tedious to format each one
individually. There are two ways to speed up
the formatting.
1. Format one series then select the next and press F4
to repeat, and so on.
2. Write a macro to format all series. Here is an
example of a macro which formats all series in all
charts on a worksheet.
Sub FormatDataSeries()
For Each Chart In ActiveSheet.ChartObjects
Chart.Activate
ActiveChart.ChartArea.Select
For Each Series In ActiveChart.SeriesCollection
Series.Select
With Selection.Border
.ColorIndex = 46
.Weight = xlThin
.LineStyle = xlDash
End With
With Selection
.MarkerBackgroundColorIndex = 40
.MarkerForegroundColorIndex = 2
.MarkerStyle = xlSquare
.Smooth = True
.MarkerSize = 6
End With
Next Series
Next Chart
End Sub
You can modify this to suit your chart. Use the macro
recorder to change the style of one data series to as
you want it, then copy the settings required to
your macro.
For more tips on charting with Excel see
http://www.windmill.co.uk/xlchart.html
For how to use Excel for data acquisition see
http://www.windmill.co.uk/excel.html
________________________________________________________
________________________________________________________
DAQ News Roundup
________________________________________________________
Welcome to our roundup of the data acquisition and
control news. If you would like to receive more
timely DAQ news updates then grab our RSS newsfeed
at http://www.windmillsoft.com/monitor.xml. Read
http://www.windmill.co.uk/newsfeed.html for notes
on how to display the news on your own web site,
read it via e-mail, mobile phone or a newsfeed viewer.
Fickle ocean current foils climate modellers
Scientists can now monitor the ocean continuously,
thanks largely to RAPID, an array of instruments
strung on cables moored to the seabed. RAPID measures
the ocean's pressure profile, which scientists can use
to calculate how water is flowing. What they see is
that the overturning circulation fluctuates wildly,
making historical comparisons difficult.
Source: New Scientist
http://environment.newscientist.com/article/dn12494-fickle-ocean-current-foils-climate-modellers.html
See what you're spewing as you drive
In future drivers may only have to glance at the
dashboard to see the pollution spewing out of their
vehicle's exhausts. A team from The University of
Manchester has constructed a laser measuring device
capable of recording levels of carbon dioxide, carbon
monoxide and methane from directly inside an exhaust.
Once optimised, the process could be incorporated
into onboard diagnostic systems that would monitor
emissions as vehicles drive along - and potentially
help people reduce their emissions by adjusting their driving style.
Source: The University of Manchester
http://www.manchester.ac.uk/
Nanoscale Blasting Adjusts Resistance in Magnetic Sensors
A new process for adjusting the resistance of
semiconductor devices by carpeting a small area of
the device with tiny pits, like a yard dug up by
demented terriers, may be the key to a new class of
magnetic sensors. The technique allows engineers to
tailor the electrical resistance of individual
layers in a device without changing any other part
of the processing or design.
Source: National Institute of Standards and Technology
http://www.nist.gov/
First Automated River-Monitoring System Planned
The first automated monitoring and forecasting
network for an American river is being set up by
The Beacon Institute and IBM. The River and Estuary
Observatory Network will allow minute-to-minute
monitoring of New York's 315-mile Hudson River.
The system will capture temperature, salinity and
pollution measurements; map fish populations via
acoustical data; and track particular fish species
through radio tagging.
Source: IBM
http://www-03.ibm.com/
Worldwide DCS Market Experiences Growth Resurgence
The Distributed Control Systems (DCS) market
experienced unprecedented growth in 2006, increasing
by over 14% compared to 2005 and it is expected to
continue growing at a healthy rate through 2011,
according to a new ARC Advisory Group study. They
conclude though, that 2006 will be the peak year
for growth.
Source: ARC Advisory Group
http://www.arcweb.com/
________________________________________________________
________________________________________________________
Data Acquisition Exhibitions
________________________________________________________
Industry LIVE
Esher, Surrey, UK
26-27 September
Exhibition focused on engineering, electronics and pharmaceuticals
http://www.industrylive.co.uk/
PTA-2007
Moscow, Russia
26-28 September 2007
Annual exhibition of technologies and equipment for process automation and embedded systems.
http://www.pta-expo.ru/en/
MSV
Brno, Czech Republic
1-5 October 2007
International engineering fair: portal for new products, innovations and key trends in engineering and other industries.
http://www.bvv.cz/msv-gb
Instrumentation South
Reading, Berkshire, UK
3-4 October 2007
Cover all aspects of the uses in industry of test, measurement, data acquisition and control.
http://www.instrumentation.co.uk/
DMS
Osaka, Japan
3-5 October 2007
Tenth design engineering & manufacturing solutions exhibition.
http://www.dms-kansai.jp/english/
________________________________________________________
________________________________________________________
* Copyright Windmill Software Ltd
* Reprinting permitted with this notice included
* For more articles see http://www.windmill.co.uk
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Windmill Software Ltd, PO Box 58, North District Office,
Manchester, M8 8QR, UK
Telephone: +44 (0)161 833 2782
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