Main Content

eventTimer

Class: matlab.DiscreteEventSystem
Namespace: matlab

Create entity timer event

Syntax

event=eventTimer(tag,delay)

Description

event=eventTimer(tag,delay) creates an event to delay an entity for a period of time. You can then schedule the timer by returning it as the output argument when implementing an event action method, such as entry.

Input Arguments

expand all

Custom tag of this entity timer event.

Time delay between current simulation time and the time that this timer event will be executed.

Output Arguments

expand all

Event that delays the entity in current event action context for a period of time.

Examples

expand all

Define a timer event.

function [entity,event] = entry(obj,storage,entity,src)        
    % Define a timer event
    % - The event is regarding the entity in current event action context
    % - The event has a custom tag 'timeout'
    % - The event will be executed 3.0 seconds later
    event = obj.eventTimer('timeout', 3.0);     
end

This example uses a custom entity storage block with one input, two outputs, and a storage element. An entity of type Part with TimeOut attribute enters the storage of the custom block to be processed. TimeOut determines the maximum allowed processing time of the parts. When a part enters the storage, two timer events are activated. One timer tracks the processing time of the part in the oven. When this timer expires, the entity is forwarded to output 1. Another timer acts as a fail-safe and tracks if the maximum allowed processing time is exceeded or not. When this timer expires, the process is terminated and the entity is forwarded to the output 2.

For more information, see Custom Entity Storage Block with Multiple Timer Events.

classdef CustomEntityStorageBlockTimer < matlab.DiscreteEventSystem
                        
    % A custom entity storage block with one input port, two output ports, and one storage. 
 
    % Nontunable properties 
    properties (Nontunable)
    % Capacity
        Capacity = 1;
    end
    
    methods (Access=protected)       
 
        function num = getNumInputsImpl(~)
            num = 1;
        end
        
        function num = getNumOutputsImpl(~)
            num = 2;
        end      
        
        function entityTypes = getEntityTypesImpl(obj)
            entityTypes = obj.entityType('Part');
        end
        
        function [inputTypes,outputTypes] = getEntityPortsImpl(obj)
            inputTypes = {'Part'};
            outputTypes = {'Part' 'Part'};
        end

        function [storageSpecs, I, O] = getEntityStorageImpl(obj)
            storageSpecs = obj.queueFIFO('Part', obj.Capacity);
            I = 1;
            O = [1 1];
        end
          
    end
  
    
   methods

        function [entity,event] = PartEntry(obj,storage,entity,source)
            % Specify event actions when entity enters storage.
             ProcessingTime=randi([1 15]);
             event1 = obj.eventTimer('TimeOut', entity.data.TimeOut);
             event2 = obj.eventTimer('ProcessComplete', ProcessingTime);   
             event = [event1 event2];
        end

        function [entity, event] = timer(obj,storage,entity,tag)
            % Specify event actions for when scheduled timer completes. 
            event = obj.initEventArray;
            switch tag
                case 'ProcessComplete'
                    event = obj.eventForward('output', 1, 0);
                case 'TimeOut'
                    event = obj.eventForward('output', 2, 0);
            end

        end
            
    end
    
end

Version History

Introduced in R2016a