Specifications

Crestron SIMPL Windows Software
simply passes all input transitions through to the output(s). Thus, you would need
some elaborate logic to reset the Delay each time a button was pressed. Second, the
Delay symbol is a single-precision symbol, meaning that the values of the ‘time’
parameters can only range from 0 to 583 seconds. This makes it impossible to create
a 3-hour wait time.
Delay Example: system power sequencing
press10
press11
fb10
fb11
Touchpanel
trig
reset
delay1 2s
delay2 5s
delay3 10s
Delay
enable
in1
in2
in3
in4
in5
out1
out2
out3
out4
out5
Buffer
enable
in1
in2
in3
in4
out1
out2
out3
out4
Buffer
System On
trig
reset
delay1 5s
Delay
System Off
1
1
Screen_down
Vproj_On
Vproj_Source_1_Sel
DVD_Play
Lights_Scene_2
Lights_Scene_1
DVD_Stop
Vproj_Off
Screen_Up
Earlier in this chapter we saw an example using Buffer symbols that allowed us to
generate multiple events from a single signal. This example provided an easy and
elegant way to create system power on/off events. One limitation of that first
example was that we had no control over when each event occurred. That is, once the
input to the Buffer was triggered, all of the outputs triggered immediately, and this is
not always acceptable. For example, during a ‘power on’ sequence you want the
projector lift to lower first, then turn on the projector, then switch to a certain source
only after the projector had ample time to turn on. The figure shows how to program
such a sequence using a Delay and a Buffer. Note that the Delay outputs are passed
through the Buffer in order to trigger the desired event. This is done so that the signal
names may be driven by other system inputs or other Buffers, as described in that
first example. Finally, notice that the signal ‘system_power_off’ is routed into the
‘reset’ input of the Delay symbol. This will prevent problems when the system on
and off buttons are pressed within a few seconds of one another (because the user
changed his mind, for example). Without resetting the Delay, a ‘system on’ function
that had yet to be processed would occur during the ‘system off’ process, causing an
undesirable situation.
Oscillator Symbol
An Oscillator symbol allows you to create a constantly alternating signal, useful for
tasks such as polling an RS-232 device for status information or blinking a feedback
indicator on a user interface. The output will only oscillate for as long as the ‘gate’
input is high, thus allowing you to turn the symbol on or off. The time that the output
signal is high and low is governed by the ‘hi_time’ and ‘lo_time’ parameters.
Primer – DOC. 6253 Crestron SIMPL Windows • 55