Windmill Software Ltd
Data Acquisition Intelligence

November 2009

The Newsletter for PC-Based Data Acquisition and Control
Issue 136     November 2009
--------------------ISSN 1472-0221----------------------

Welcome to Monitor, the data acquisition and control 
newsletter.  I hope you find it useful, but should you 
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* Windmill Notes: How to use Windmill to Control 
  Analogue Outputs
* Excel Corner: How to Place Event Markers in Charts
* DAQ News Roundup

Windmill Notes: How to use Windmill to Control 
Analogue Outputs

Analogue output signals fall broadly into one of two 
categories: control and waveform generation. When they 
are used as control signals, they are generally slowing 
changing. The computer might be monitoring one or more 
input signals and using these to calculate a control 
signal. Alternatively, it may generate an output voltage 
as a stimulus prior to measuring the response.  It is 
analogue output control that we are looking at today.

Windmill has several programs which you can use to 
control your analogue outputs, including AnalogOut, 
Graphics and Test-Seq.  Additionally, the 
Windmill IML Tools make it easy for you control 
outputs from your own macros and programs.

Windmill AnalogOut for Simple Output Control
  AnalogOut is included in the standard Windmill suite 
  of data acquisition software  
  You can drive AnalogOut from the mouse, keyboard or  
  from another application like Excel.  It is extremely 
  simple to use and tells one or more analogue output 
  channels which value they should be generating. 

Windmill Graphics for Customised Windows
  Graphics lets you design your own user interface.   
  Amongst other things you can insert buttons to control  
  analogue outputs.  You can use a standard button or  
  draw your own.  When someone clicks your button they  
  will be asked for a value to send to the analogue  
  output.  You can also set Graphics to automatically  
  send a pre-entered value when it starts running.  
  For more details see

Windmill Test-Seq for Sequence Control of Equipment
  Test-Seq interprets a file of commands and controls  
  equipment and software accordingly.  It can send 
  commands and data to other Windows programs, or directly 
  to the hardware inputs and outputs.  Use Test-Seq to 
  control analogue outputs according to timing or 
  environmental conditions.  For more details see

Windmill IML Tools
  You can use the IML Tools to control analogue outputs
  directly from Windows applications like Excel, from 
  JavaScript code running on a web page, from Visual
  Basic programs or from any developer tool that can 
  integrate Active X controls.  Windmill takes care of 
  the communication with the hardware leaving you 
  free to concentrate on your application. For more 
  details see 

The Windmill programs mentioned can be used with 
equipment connected to the PC over, for example, Ethernet, 
USB, RS232, RS422, RS485 or Modbus.  Contact Windmill 
Software at [email protected] for more information, 
or fill in the form at

Excel Corner: How to Place Event Markers in Charts

It's easy enough to plot a chart of automatically logged 
data, but how do you add events that are not 
automatically logged?  For instance, if you were 
recording how many people entered a store each day you 
might want to mark when you started a sale or an 
advertising campaign.

Here is how to do it. We also have an example 
spreadsheet you can download at

1. At its simplest your spreadsheet will have dates in 
   column A and counts in column B.

2. In an empty column, insert a data value against the 
   date your event occurred. Make this a little higher 
   than any of your logged data.

3. Create an xy scatter chart with time on the x axis 
   and your data and event columns on the y axis.

4. Right click the event data point on the chart and 
   choose "Format Data Series".

5. Choose the "Y Error Bar" tab and add a minus error bar 
   with the event value.

6. Choose the Data Labels tab and add the series name label. 
   Click this on the chart and edit it to describe your event.

7. On the chart, right click the error bar and use the 
   patterns tab to format it as the same colour as the event 
   data point.

8. You now have a marker showing when your event occured 
   and what it was.

9. You could add other markers, for example to show when 
   an advertising campaign ended.  To join up the event markers, 
   from the Excel Tools menu choose Options, Chart, Interpolated.

Any questions? Take a look at the example spreadsheet at

Further Reading
Excel charting tips
Excel data acquisition tips

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  Read for notes
on how to display the live news on your own web site.

Piezoelectronics gets green makeover
   A new generation of lead-free piezoelectric materials 
   could lead to greener actuators, sensors and even 
   ultra-dense data storage. The new materials, which 
   generate an electric field when squeezed, copy the 
   crystal structure of conventional piezoelectric 
   materials but use bismuth instead of lead. 
   Source: New Scientist

First open specification for battery-less wireless sensors
   The EnOcean Alliance is publishing the first open 
   specification for energy harvesting wireless sensors 
   which ensures interoperability between products of 
   different manufacturers. The specification contains 
   50 equipment profiles supporting the development of 
   building automation, such as switches, remote controls, 
   sensors, sensor combinations and data of every kind.
   Source: EnOcean Alliance

Variable Speed Drives in Home Appliances to Double by 2013
   The use of inverter-based variable speed drives (VSD) 
   in home appliances is forecast to double over the next 
   five years according to IMS Research. Currently, 
   appliances with VSD account for just one in eight new 
   appliances - mainly air conditioners and washing machines. 
   Variable speed motor controls allow greater efficiency, 
   more reliable performance and quieter operation. 
   Source: IMS Research

Ocean Robots to Monitor Oil Spills
   Swarms of miniature robotic ocean explorers could one day 
   help predict where ocean currents will carry oil spills.
   Source: SCUBA News

Efficiency gains for wind turbines
   A new type of hydraulic technology could be used to 
   build more reliable and less expensive transmission 
   systems for wind turbines, its developers have claimed.
   Source: The Engineer

* 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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