16
LDS4 Colour Display System
© 2009 General Engine Management Systems Ltd.
LDS4 Colour Display System
4.9
Time Filter Sensor
Normally, outputs send data to gauges as fast as possible. However, by creating an output using
a time filter sensor, it is possible to specify the update rate of the output which is useful for
making rapidly changing values more legible. Furthermore, a time filter sensor can be used to
perform a rolling average, minimum or maximum on the input value which is useful for filtering
noisy inputs.
To edit the Time Filter sensor values, click the ellipsis button (...) to show the time filter editor:
The Time Filter parameters have the following meanings:
·
Update period: Specifies the rate at which values are sent to outputs and gauges used by
this output. For example, if the Update Period is set at 1000, a gauge displaying the value
from this output will update once per second. If 0 is specified, the output will update as fast
as possible.
·
Rolling period: Specifies the time period over which the rolling function is calculated. If zero
is specified, the rolling period is set to the update period.
·
Rolling function: Specifies how the value produced from the output is calculated:
·
Maximum: The output is the maximum value occurring during the last (rolling period)
milliseconds.
·
Minimum: The output is the maximum value occurring during the last (rolling period)
milliseconds.
·
Average: The output is the average of all values occurring during the last (rolling period)
milliseconds.
·
Current: The output is the last received value. This effectively disables the rolling period
function.
The following table illustrates the results from a Time Filter assuming that input data is coming in
at 10ms, the rolling period is set to 30ms and the update period is set to 0ms:
T
(ms)/
(fn)
0
10
20
30
40
50
60
70
80
90
100
110
120
130
140
Input 0
1
2
3
4
5
6
7
8
9
10
9
8
7
6
Max 0
1
2
3
4
5
6
7
8
9
10
10
10
10
9
Min 0
0
0
0
1
2
3
4
5
6
7
8
8
7
6
Avera
ge
0
0.5
1
1.5
2.5
3.5
4.5
5.5
6.5
7.5
8.5
9
9
8.5
7.5
Curre
nt
0
1
2
3
4
5
6
7
8
9
10
9
8
7
6
Summary of Contents for LDS4
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