DCT Antares SB, Руководство пользователя

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5.6. SPEED VIOLATION (WITH WARNING) REPORT
5.6.1 Setting the speed limit
Up to 10 speed limits can be defined on the unit, for no particular reason
we choose the limit
07
. Using the
GS
message we set the limit:
>
SGS0710650
<
Now any time the vehicle speed is above 65mph the
S07
signal is going
to be true.
5.6.2 Start a counter
In order for the violation to be reported only after a continuous-15-seconds
condition, a timer has to be initiated whenever the speed goes above
65mph
.
To do so we create a silent event, that is it an event which only function is
to start a timer but not to send any report:
>
SED40SV0;S07+;ACT=SGC00TC00015
<
We used event
40
for no particular reason other than it is free to be used.
The event triggers whenever
S07
signal changes to
true
, that is it, whenever
the vehicle’s speed goes beyond
65mph
. The event includes an user-action:
Starting timer
00
with a threshold value of 15 seconds. This will make signal
C00
go true 15 seconds after the counter definition, that is it, 15 seconds
after the speed violation is detected.
5.6.3 Creating the violation report
Having
C00
signal become true 15 seconds after the speed violation the only
thing left to do is create the violation event, the event
10
:
>
SED10NV4;C00+
<
This one as you can see is not a silent event: It sends a report to
DA 4
which according to the example we have been working points to the remote
AVL server.
5.6.4 Something is missing...
So far so good, it does what it is asked. But we are missing a silent event
which turns off the counter whenever the driver slows down before the 15
seconds, or else the violation is going to be reported even though the driver
did the right thing. To do so we create another silent event which undefines
the
C00
counter whenever the speed falls below the limit:
>
SED41SV0;S07-;ACT=SGC00U
<
This will guarantee that the counter won’t activate signal
C00
if the speed
falls below the limit before 15 seconds.
5.6.5 Driving the LED
In order to lit LED connected to output 1 when the actual speed is greater
than the speed limit, we create a silent event that drives output 1 high when
the speed goes beyond the limit:
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