Timer
The Timer object is used to create delays or trigger events after a defined elapsed time. It should be used instead of Lua's native delay and time functions.
Timer.CallAfter()Creates a simple timer that calls a named function after a specified delay time.
Description
As an alternative to creating a traditional named timer, you can create a simple timer to call a named function after a given delay period. Unlike named timer objects created with Timer.New(), there is no need to issue a :Stop() command to halt repetition of this timer.
Syntax
Timer.CallAfter(function, delay)
Arguments
function : The named function to call after the specified delay time.
delay : [seconds.milliseconds]
Timer.New()Creates a named timer using Start and Stop methods.
Description
Each Timer must be named when created which is then the means by which you manipulate each specific timer. The Timer:Start method is used to start the timer and set the delay time. When the delay time has elapsed, the function specified in Timer.EventHandler is called. By default, Timer repeats when it has elapsed. Timer:Stop is used to stop the timer. Timer:IsRunning prints if timer is running.
Syntax
Timer.New()
Creates a new timer object.
.EventHandler
Calls a specified function when the delay time has elapsed.
:Start(period in seconds)
Starts the timer.
:Stop()
Stops the timer.
:IsRunning()
Returns true if the timer is running.
Examples
timer1 = Timer.New()
timer2 = Timer.New()
function timerFunc(timer)
if timer == timer1 then
print( "timer 1!" )
elseif timer == timer2 then
print ( "timer 2" )
end
end
timer1.EventHandler = timerFunc
timer2.EventHandler = timerFunc
timer1:Start(1)
timer2:Start(2)
TestTimer = Timer.New()
TestTimer:Start(1)
print(TestTimer:IsRunning()) -- should print true
TestTimer:Stop()
print(TestTimer:IsRunning()) -- should print falseReturns the number of seconds since epoch.
Description
Timer.Now() returns the number of seconds since the epoch. It can be useful to calculate the difference between a current value and a previous value.
Note: The returned epoch value differs between Emulation mode (from Windows) and Run mode (from the Q-SYS Core processor).
Syntax
Timer.Now()
Example
print (Timer.Now())Debug Output
2021-11-22T23:16:08.884 Starting Script 2021-11-22T23:16:08.884 13282096568.884
Troubleshooting
Issues with Timers Stalling or Stopping
Do not scope your Timers locally. If you do so, the scripting engine will eventually delete the timer and the event callback, forcing it to stop.
Note: If you see issues with Timers stalling and have your Timer scoped locally, try removing the “local” from the Timer declaration.
Example 1: Timer Stops Erroneously
In the following example, an EventHandler will print an Event at 1 second intervals; however, since it is prefixed by local, the Timer was stopped after 22 iterations.
local tmr = Timer.New()
count = 0
tmr.EventHandler = function()
print("Event:"..count)
count=count+1
end
tmr:Start(1)Debug Output
2023-01-31T18:23:47.061 Starting Script 2023-01-31T18:23:49.060 Event:1 2023-01-31T18:23:50.059 Event:2 2023-01-31T18:23:51.060 Event:3 2023-01-31T18:23:52.059 Event:4 2023-01-31T18:23:53.060 Event:5 2023-01-31T18:23:54.060 Event:6 2023-01-31T18:23:55.060 Event:7 2023-01-31T18:23:56.060 Event:8 2023-01-31T18:23:57.059 Event:9 2023-01-31T18:23:58.059 Event:10 2023-01-31T18:23:59.059 Event:11 2023-01-31T18:24:00.060 Event:12 2023-01-31T18:24:01.060 Event:13 2023-01-31T18:24:02.060 Event:14 2023-01-31T18:24:03.059 Event:15 2023-01-31T18:24:04.060 Event:16 2023-01-31T18:24:05.059 Event:17 2023-01-31T18:24:06.060 Event:18 2023-01-31T18:24:07.060 Event:19 2023-01-31T18:24:08.060 Event:20 2023-01-31T18:24:09.059 Event:21 2023-01-31T18:24:10.059 Event:22
Example 2: Removing Local Resolves Timer
tmr = Timer.New()
count = 0
tmr.EventHandler = function()
print("Event:"..count)
count=count+1
end
tmr:Start(1)Debug Output
2023-01-31T17:33:18.522 Starting Script .... 2023-01-31T18:23:18.522 Event:90 2023-01-31T18:23:19.522 Event:91 2023-01-31T18:23:20.522 Event:92 2023-01-31T18:23:21.522 Event:93 2023-01-31T18:23:22.523 Event:94 2023-01-31T18:23:23.523 Event:95 2023-01-31T18:23:24.522 Event:96 2023-01-31T18:23:26.522 Event:98 2023-01-31T18:23:27.523 Event:99 2023-01-31T18:23:28.523 Event:100 2023-01-31T18:23:29.522 Event:101 2023-01-31T18:23:30.522 Event:102 2023-01-31T18:23:31.522 Event:103 2023-01-31T18:23:32.523 Event:104 2023-01-31T18:23:33.523 Event:105 2023-01-31T18:23:34.522 Event:106 2023-01-31T18:23:35.523 Event:107 2023-01-31T18:23:36.522 Event:108 2023-01-31T18:23:37.523 Event:109 2023-01-31T18:23:38.523 Event:110 2023-01-31T18:23:40.523 Event:112 2023-01-31T18:23:41.523 Event:113 2023-01-31T18:23:42.522 Event:114 2023-01-31T18:23:43.523 Event:115 2023-01-31T18:23:44.522 Event:116 2023-01-31T18:23:45.522 Event:117 2023-01-31T18:23:46.522 Event:118 ....
