DCT e-track, Руководство пользователя, Страница: 108 / 212

4.22. SCENARIOS AND EXAMPLES (SCRIPTS)
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 traveling speed is above 65mph the
S07
signal
is going to be true.
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 purpose is to start a timer but not to send any report:
>
SED40SV0;S07+;ACT=SGC00TC00015;ACT=SXAZZ1
<
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 traveling 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 defini-
tion, that is it, 15 seconds after the speed violation is detected. The
other user-action indicates to start an audible alert. The
XAZZ1
com-
mand makes e-track
TM
beep every second. This is a driver’s warning
to slow down.
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;S07C00&+;ACT=SXAZZ2
<
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 Tracking Server. It includes an user-action to change the
one-second beep to a single long beep. This indicates the driver that
the report has actually been generated.
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. Also, it is needed to stop
106