Waits And Timer Keywords; Controlling Time In Axcess; The Wait List - AMX AXCESS CONTROL SYSTEM PROGRAM Instruction Manual

Waits and Timer Keywords

Controlling Time in Axcess

There are several of timing keywords available in Axcess. Functions can be delayed for a few
seconds, or they can be delayed until certain conditions are right. The built-in stopwatch allows you
to measure time intervals between operations in your program. For example, you can program
Axcess to start playing a tape precisely on Saturday at 3:15 PM. This section describes the timing
keywords and how to apply them to your programs.

The Wait List

The most common keyword relating to time is WAIT. The WAIT keyword is used to activate
functions after a specified delay time has elapsed. When a WAIT is encountered, Axcess places the
WAIT statement into a list in memory and continues on with the rest of the program. After each
pass through mainline, the Central Controller scans this wait list, and if any WAITS have come due,
Axcess executes the statement or compound statement immediately following the expired WAIT
keyword. Up to 50 WAITS are allowed in the list at a time.
Time is measured in tenths of a second. A WAIT of 10 is one second, a WAIT of 15 is one and a
half seconds, a WAIT of 20 is two seconds, and so on.
An example application of a time delay would be if your system has two relays controlling system
power. One could be for the audio amplifier, and the other for the rest of the equipment (rack
power). In these cases, a time delay is desired between powering up the source equipment and
powering up the audio amplifier, to avoid noise.
In your program, you will first add a constant definition for your new relay and change the name of
the existing system power relay to RACK_POWER. If you use relay 7 (the next available relay on
the card), the line to add to the DEFINE_CONSTANT section looks like this:
DEFINE_CONSTANT
AMP_POWER
You will also change the constant identifier SYS_POWER to RACK_POWER. When the System
Power button is activated, you want the rack power to come on first (relay 3). After a 1-second
delay, the amp power should turn on. When you turn the power off, you want the reverse to happen.
Here's the new code for the System Power button:
Axcess Programmnig Language
= 7
Waits and Timer Keywords
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