Windmill Software Ltd
Windows Engineering Software

October 2004

The Newsletter for PC-Based Data Acquisition and Control
Issue 75        October 2004
--------------------ISSN 1472-0221----------------------

Welcome to the 75th issue of Monitor.  We hope you 
enjoy it, but should you wish to cancel your 
subscription you can do so at

* Windmill News: Windmill Helps Locate Oil Contamination
* Windmill Notes: 
  Creating a User Interface with Windmill Graphics
* Excel Corner: 
  Showing Only Recent Data in a Chart

Windmill News: Windmill Helps Locate Oil Contamination

When underground water is contaminated by oil, 
environmental agencies need to find the source and 
extent of the pollution.  Traditionally this has been 
difficult to establish, but researchers at the 
University of Waterloo (Canada) are working on an 

The scientists inject a solution of bromide and other 
tracer chemicals into the water.  When these tracers hit 
the contamination, some are delayed more than others.  
Downstream, the team continuously pump up the water 
and monitor the tracer chemicals.  The differences in 
breakthrough times of each tracer lets them estimate the 
total mass and distribution of the subsurface oil pools.

To accurately measure the breakthrough of bromide they 
use Windmill Software and an Orion 290 A+ meter 
equipped with a bromide selective electrode.  Dr Niels 
Hartog, one of the scientists involved in the project, 
  "With Windmill reading the serial output of the meter, 
   I was easily able to continuously log bromide 
   concentrations in the extraction wells."

Windmill stores the data in a text file which can later 
be imported into almost any Windows analysis software, 
such as Excel.  The handheld Orion meter, for performing 
pH and concentration measurements, is just one of the 
many devices which can be handled by the Windmill data 
acquisition software. 

To use Windmill for this type of application you need 
its serial driver.  Details of the latest version of 
this, COMIML, are at  
Alternatively, as a subscriber to this newsletter you 
can download an older version (LabIML) for free.

To quickly configure the software for use with the Orion 
meter go to and 
download the set-up files.

For more on Windmill software see

Windmill Notes: 
Creating a User Interface with Windmill Graphics

You can create your own display and control windows with 
the Windmill Graphics program. Graphics customises the 
Windmill software suite, making a versatile system that 
is unique to your application. The window continuously 
reflects the state of the system in the real world. Once 
you've created a window you can protect it from further 
editing. You can make the display a simple front end, or 
show enough detail to keep the even the most data hungry 
happy. Virtual instruments, process mimics, annunciator 
panels, wiring diagrams... it's entirely up to you. 

To use Windmill Graphics you just: 
1. Create a background in any painting package 
   supporting bitmaps, Windows Paint for example.

2. Open the bitmap in Windmill Graphics and double-click 
   the mouse where you want live text or graphics to 

3. Choose the type of live item and set its options. 

4. Switch to protected run mode and see the window come 
   to life, continuously updating with real-world data. 

Eight types of live item are available: 
- Analogue meters 
- Moving bars 
- Changing icons (eg open and closed valves) 
- Data readings with colour-coded alarms 
- Time and date labels 
- Analogue control buttons 
- Digital control buttons 
- Program control buttons 

Tips on Creating a Background Image

1. Start by using your painting package to set the size 
   of your background. (Graphics always displays the 
   background the same size as it was created.) Make sure 
   you do not create an image that exceed the resolution of 
   your screen, as Graphics cannot scroll images. Remember 
   that Graphics will need additional room for a title bar.

2. You may find it useful to write down the co-ordinates 
   of where you later intend to add dynamic items to the 
3. In areas where you intend to add dynamically changing 
   icons, draw the icon in the off state - for example a 
   closed valve. You can then copy the valve, edit it to be 
   an open valve and save it in its own file. This ensures
   that both the on and off versions of the icon are the
   correct size and colour.

When you have created a background you are ready to use 
Graphics, and drop the dynamic items into their places.

Further Reading
Tutorial on designing the user interface: process 
mimics, HMIs, etc...
More on Windmill Graphics

Excel Corner: 
Showing Only Recent Data in a Chart

One of our readers asked if it were possible to create 
a chart that only showed recent data and automatically 
refreshed itself as new data arrives.  We discussed how 
to create an automatically refreshing chart in issue 
62 of Monitor, which is available at

You can adapt this method to only show the most recent 
data, the last hour's or week's for example. To do this:

1. In the first cell of an empty column of the 
   spreadsheet, enter the number of rows of data you 
   want to chart.  For example, if you are logging data 
   every minute and want to show the last hour's 
   readings: enter 60.

2. When defining the range "ColB", enter 
   Sheet1 is the name of your worksheet
   $G$1 is the cell containing the number of rows of
   data to be charted.

Further Reading
For more on using Excel with Windmill see
For more on charting with Excel see

* Copyright Windmill Software Ltd
* Reprinting permitted with this notice included
* For more articles see

We are happy for you to copy and distribute this 
newsletter, and use extracts from it on your own web site 
or publication, providing the above notice is 
included and a link back to our website is in place.

An archive of previous issues is at
and an index of articles at

Windmill Software Ltd, PO Box 58, North District Office,
Manchester, M8 8QR, UK
Telephone: +44 (0)161 833 2782
Facsimile: +44 (0)161 833 2190
E-mail: [email protected]


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