Windmill Software Ltd
Windows Engineering Software

June 2006

The Newsletter for PC-Based Data Acquisition and Control
Issue 95           June 2006
--------------------ISSN 1472-0221----------------------

Welcome to the midsummer issue of Monitor (at least it 
is here in the Northern hemisphere). We hope you enjoy 
it, but should you wish to cancel your subscription you 
can do so at

* Windmill News: 
  Counting Passengers on Public Service Buses
* Windmill Notes:
  Getting Started with the Windmill 6 Serial Package
* Choosing the Right Range and Resolution
* DAQ News Roundup

Windmill News: 
Counting Passengers on Public Service Buses

21st Century Crime Prevention Services Limited are 
using Windmill's VT Collect software to count passengers 
entering and leaving a vehicle.  The information 
collected will be interfaced with fare revenue data 
from the ticketing machines.  Eventually the system 
will automatically transmit an audit report back to 
the control centre as each bus returns to its depot. 

The company expects that the system will give greater 
control on revenue and reduced running costs for bus 
operators up and down the country.

Windmill Notes: Getting Started with the 
Windmill 6 Serial Package

Lets imagine you've installed the Windmill 6 software 
to interface RS232, RS485 and Modbus devices to 
your PC. 

What do you do next? 

1. Run ComDebug.
2. Follow the steps in our Getting Started with COMIML
   section. (Or click the ComDebug Help button and go 
   to the Getting Started section there.)
3. Run ConfIML and add the "COMIML Serial Instrument 
4. Run SetupIML and give names to your data channels, 
   set measurement units, signal ranges, etc.
5. Run Chart, Logger or one of the other Windmill 
   programs and start to read and display data.
6. If you wish, transfer the readings to Excel.

What about in future?

1. Skip steps 1 to 4 above and go straight to using
   the Windmill logging, charting, display and 
   control programs.

All the Windmill programs have Help files associated 
with them.  You can download the latest versions of 
these Help files from

For more on transferring data to Excel see

Choosing the Right Range and Resolution

Most analogue sensors produce a voltage, including 
thermocouples, strain gauge bridges and gas 
concentation probes.  This is converted to a form the 
computer can understand by an analogue-to-digital (A-D) 

The input range (or gain range) of an A-D coverter 
refers to the maximum and minimum voltage that 
it can accept.

An input range may be bipolar, covering a range from 
-50 mV to +50 mV for example; or unipolar, perhaps 
covering a range of 0 to 50 mV.  Many A-D converters 
have an actual range of 0 to 10 V, so an input signal 
with a range of 0 to 50 mV needs to be amplified by a 
gain of 200 before it can be converted.  Many systems 
offer a choice of ranges, and you can select the most 
appropriate using software like Windmill. 

You should always choose the smallest range that 
encompasses your signal, as this optimises the 

The resolution is the number of steps into which the 
input range is divided.  The resolution is usually 
expressed as bits (n) and the number of steps is 
((2 to the power n) - 1).  This equates to 
(2 to the power n) values.  A converter with 
12-bit resolution, for instance, divides the range 
into 212, or 4096, values.  In this case a 0-10 V 
range will be resolved to 2.5 mV, and a 0-100 mV 
range will be resolved to 0.025 mV. 

Although the resolution increases when you narrow the 
range, there is no point in trying to resolve signals 
below the noise level of the system: all you will get 
are unstable readings. 

Some A-D converters have a choice of resolutions 
(offering 12-, 13-, 14-, 15- and 16-bit for example). 
You can choose the most suitable for your 
application, balancing speed against accuracy.

For more data accquisition tips and techniques, see the 
Windmill web site at

DAQ News Roundup

Welcome to our roundup of the latest findings in 
data acquisition and control.  

If you would like to receive more timely DAQ news updates 
then grab our RSS newsfeed at  Read for 
information how.

Virbration Monitor provides Landslide early Warning
   A device that provides early warning of a landslide 
   by monitoring vibrations in soil is being tested by 
   UK researchers.  The instrument comprises a steel 
   pipe dropped into a borehole in a slope. The borehole 
   is filled in with gravel around the pipe to help 
   transmit high-frequency vibrations generated by 
   particles within the slope. These vibrations pass up 
   the tube and are picked up by a sensor on the surface. 
   Software analyses the vibration signal to determine 
   whether a landslide may be imminent.   
   Source: New Scientist

Temperature Sensitivity Identified in Circuit Boards	
   Electrical circuits may act differently in cold 
   climates than they do in warm - potentially affecting 
   the performance of computers and other electronics.  
   A new technique identifies and quantifies an important 
   cause of this temperature sensitivity.
   Source: National Institute of Science and Technology

Substantial Growth Predicted for Wireless in Automation
   The world market for wireless communications in 
   automation is forecast to grow at 28 percent per 
   year over the next 5 years, according to IMS Research. 
   Wireless communications is not widely used within the 
   automation environment at present, but a proliferation 
   of new products is being introduced currently.
   Source: IMS Research

Extra-Sensitive Touch Sensor Developed
   An artificial touch sensor as sensitive as a human 
   fingertip has been developed by US scientists.  To 
   make the sensor researchers deposited alternating 
   layers of gold and cadmium sulphide nanoparticles, 
   separated by insulating layers of polymer.  They 
   then applied a voltage across the film.  As a 
   result, when pressure is exerted on the material 
   its layers squeeze together allowing current to 
   flow.  As the current flows through different regions 
   of the material it causes the cadmium sulphide 
   nanoparticles to emit light, creating an image that 
   can be picked up by a digital camera.
   Source: New Scientist


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

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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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