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Getting started 4
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2 Getting started
2.1
Software updates
Our software is regularly updated with new features. To check what version of the
software you are running, start PicoScope or PicoLog and select the
Help | About
menu. The latest version of software can be downloaded free of charge from the
DrDAQ web site at
http://www.drdaq.com . Alternatively, the latest software can be
purchased on disk or CD from Pico Technology.
To be kept up-to-date with news of new software releases join our e-mail mailing list.
This can be done from the main Pico Technology web site at
http://www.picotech.
com/ .
2.2
USB DrDAQ scaling files (.DDS)
The DrDAQ driver has built-in scaling for each of the built-in and Pico-supplied
sensors. You can incorporate scaling for your own sensors by adding a file called
scaling.dds
(where 'scalin g' can be replaced with a name of your choice
)
. This
file will contain the details of your sensor.
The values returned by the driver are integers that represent fixed-point decimal
numbers. For example, the driver treats pH as a value with two decimal places, so a
pH of 7.65 is returned as 765.
You can call the routine UsbDrDaqGetChannelInfo to find out how many decimal
places a channel is using, and also to get a divider that converts the integer value to
the corresponding real number. For pH, the returned divider is 100, so 765 divided by
100 gives 7.65.
For some sensors, there is more than one possible scaling available. You can call
UsbDrDaqGetScalings to get a list of valid scaling codes, then call
UsbDrDaqSetScalings to select one of them. Once selected,
UsbDrDaqGetChannelInfo will return full information about the selected scaling. If
you do not use UsbDrDaqSetScalings , the driver will automatically select the first
available scaling for each channel.
USB DrDAQ scaling files can be used to supplement the scalings built into the driver.
Several DDS files may be used, and these must be placed in the current working
directory where the USB DrDAQ software is installed. The total number of sets of
scaling data in all the files used must not exceed 99.
Each scaling file may contain more than one set of scaling data. Each scaling must
have a unique scaling number, contained in the
[Scale...]
section heading.
A set of typical entries from a
.DDS
file is shown below:
[Scale1]
Resistor=1
LongName=CustomTemperature1
ShortName=TempC
Units=C
MinValue=-40
MaxValue=120
OutOfRange=0
Places=1
Method=0
IsFast=Yes
NoOfPoints=32
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