User manual

USB DrDAQ User's Guide 35
Copyright © 2011 Pico Technology Ltd. All rights reserved. usbdrdaq.en
3.7.5
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 'scaling' can be replaced with a name of your choice). This
file will contain the details of your sensor.
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
Raw1=2.385
Scaled1=-30
...
Raw32=1.32
Scaled32=100
[Scale2]
Resistor=2.2
LongName=CustomTemperature2
ShortName=TempF
Units=F
MinValue=32
MaxValue=160
...
[Scale3]
Resistor=3.3
LongName=CustomLight
ShortName=Light
Units=lux
MinValue=0
MaxValue=20000
...
The meanings of the terms in the .DDS file are as follows:
[Scale1]
A unique number, from 1 to 99, to identify this entry. (Pico-created numbers are
from 100 upwards.)
Resistor=1
The ID resistor value in kiloohms. In this example "1" represents 1k, "2.2"
represents 2k2 and so on.
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