timer (MATLAB Functions)

Construct timer object

Syntax

T = timer
T = timer(`PropertyName1', PropertyValue1, 'PropertyName2', 
PropertyValue2,...)

Description

T = timer constructs a timer object with default attributes.

T = timer('PropertyName1', PropertyValue1, 'PropertyName2', PropertyValue2,...) constructs a timer object in which the given property name/value pairs are set on the object. See Timer Object Properties for a list of all the properties supported by the timer object.

Note that the property name/property value pairs can be in any format supported by the set function, i.e., property/value string pairs, structures, and property/value cell array pairs.

Examples

This example constructs a timer object with a timer callback function handle, mycallback, and a 10 second interval.

t = timer('TimerFcn',@mycallback, 'Period', 10.0);

See Also

delete, disp, get, isvalid, set, start, startat, stop, timerfind, timerfindall, wait

Timer Object Properties

The timer object supports the following properties that control its attributes. The table includes information about the data type of each property and its default value.

To view the value of the properties of a particular timer object, use the get function. To set the value of the properties of a timer object, use the set function.

Property Name
Property Description
Data Types, Values, and Defaults

AveragePeriod
The average time between TimerFcn executions since the timer started.
Note: Value is NaN until timer executes two timer callbacks.
Data type:Default:
Read only:
double NaNAlways

BusyMode
Action taken when a timer has to execute TimerFcn before the completion of previous execution of TimerFcn.
'drop' -- Do not execute the function.

'error' -- Generate an error.

'queue' -- Execute function at next opportunity.

Data type:
Values:

Default:
Read only:
Enumerated string
'drop' 'error' 'queue'
'drop'
While Running = 'on'

ErrorFcn
Function that the timer executes when an error occurs. This function executes before the StopFcn. See Creating Timer Callback Functions for more information.
Data type:

Default:
Read only:
Text string, function handle, or cell array
None
Never

ExecutionMode
Determines how the timer object schedules timer events. See Timer Execution Modes for more information.
Data type:
Values:

Default:
Read only:
Enumerated string
'singleShot'
'fixedDelay'
'fixedRate'
'fixedSpacing
'singleShot'
While Running = 'on'

InstantPeriod
The time between the last two executions of TimerFcn.
Data type:
Default:
Read only:
double NaN Always

Name
User-supplied name
Data type:
Default:

Read only:
Text string
'timer-i', where i is a number indicating the ith timer object created this session.
To reset i to 1, execute the clear classes command.
Never

ObjectVisibility
Provides a way for application developers to prevent end-user access to the timer objects created by their application. The timerfind function does not return an object whose ObjectVisibility property is set to 'off'. Objects that are not visible are still valid. If you have access to the object (for example, from within the M-file that created it), you can set its properties.
Data type:
Values:

Default:
Read only:
Enumerated string
'off' 'on' 'on'Never

Period
Specifies the delay, in seconds, between executions of TimerFcn.
Data type:
Value:

Default:
Read only:
doubleAny number > 0.001
1.0
While Running = 'on'

Running
Indicates whether the timer is currently executing.
Data type:
Values:
Default:
Read only:
Enumerated string
'off' 'on' 'off'Always

StartDelay
Specifies the delay, in seconds, between the start of the timer and the first execution of the function specified in TimerFcn.
Data type:
Value:
Default:
Read only:
doubleAny number >= 0
0
While Running ='on'

StartFcn
Function the timer calls when it starts. See "Creating Timer Callback Functions for more information.
Data type:

Default:
Read only:
Text string, function handle, or cell array
None
Never

StopFcn
Function the timer calls when it stops. The timer stops when
You call the timer stop function

The timer finishes executing TimerFcn, i.e., the value of TasksExecuted reaches the limit set by TasksToExecute.

An error occurs
(The ErrorFcn is called first, followed by the StopFcn.)

See Creating Timer Callback Functions for more information.
Data type:

Default:
Read only:
Text string, function handle, or cell array
None
Never

Tag
User supplied label
Data type:
Default:
Read only:
Text string
''(empty string)
Never

TasksToExecute
Specifies the number of times the timer should execute the function specified in the TimerFcn property.
Data type:
Value:
Default
Read only:
doubleAny number > 0
1
Never

TasksExecuted
The number of times the timer has executed TimerFcn since the timer was started.
Data type:
Value:
Default:
Read only:
double
Any number >= 0
0
Always

TimerFcn
Timer callback function. See Creating Timer Callback Functions for more information.
Data type:

Default:
Read only:
Text string, function handle, or cell array
None
Never

Type
Identifies the object type
Data type:
Value:
Read only:
Text string
'timer'Always

UserData
User-supplied data
Data type:
Default:
Read only:
User-defined
[]Never

Property Name	Property Description	Data Types, Values, and Defaults
`AveragePeriod`	The average time between `TimerFcn` executions since the timer started. Note: Value is `NaN` until timer executes two timer callbacks.	Data type:Default: Read only:	`double NaN`Always
`BusyMode`	Action taken when a timer has to execute `TimerFcn` before the completion of previous execution of `TimerFcn`. `'drop'` -- Do not execute the function. `'error'` -- Generate an error. `'queue'` -- Execute function at next opportunity.	Data type: Values: Default: Read only:	Enumerated string `'drop' 'error' 'queue'` `'drop'` While `Running` = `'on'`
`ErrorFcn`	Function that the timer executes when an error occurs. This function executes before the `StopFcn`. See Creating Timer Callback Functions for more information.	Data type: Default: Read only:	Text string, function handle, or cell array None Never
`ExecutionMode`	Determines how the timer object schedules timer events. See Timer Execution Modes for more information.	Data type: Values: Default: Read only:	Enumerated string `'singleShot'` `'fixedDelay'` `'fixedRate'` `'fixedSpacing` `'singleShot'` While `Running = 'on'`
`InstantPeriod`	The time between the last two executions of `TimerFcn`.	Data type: Default: Read only:	`double NaN Always`
`Name`	User-supplied name	Data type: Default: Read only:	Text string `'timer-i'`, where `i` is a number indicating the `i`th timer object created this session. To reset `i` to 1, execute the `clear classes` command. Never
`ObjectVisibility`	Provides a way for application developers to prevent end-user access to the timer objects created by their application. The `timerfind` function does not return an object whose `ObjectVisibility` property is set to `'off'`. Objects that are not visible are still valid. If you have access to the object (for example, from within the M-file that created it), you can set its properties.	Data type: Values: Default: Read only:	Enumerated string `'off' 'on' 'on'`Never
`Period`	Specifies the delay, in seconds, between executions of `TimerFcn`.	Data type: Value: Default: Read only:	`double`Any number > 0.001 1.0 While `Running` = `'on'`
`Running`	Indicates whether the timer is currently executing.	Data type: Values: Default: Read only:	Enumerated string `'off' 'on' 'off'`Always
`StartDelay`	Specifies the delay, in seconds, between the start of the timer and the first execution of the function specified in `TimerFcn`.	Data type: Value: Default: Read only:	`double`Any number >= 0 0 While `Running` =`'on'`
`StartFcn`	Function the timer calls when it starts. See "Creating Timer Callback Functions for more information.	Data type: Default: Read only:	Text string, function handle, or cell array None Never
`StopFcn`	Function the timer calls when it stops. The timer stops when You call the timer `stop` function The timer finishes executing `TimerFcn`, i.e., the value of `TasksExecuted` reaches the limit set by `TasksToExecute`. An error occurs (The `ErrorFcn` is called first, followed by the `StopFcn`.) See Creating Timer Callback Functions for more information.	Data type: Default: Read only:	Text string, function handle, or cell array None Never
`Tag`	User supplied label	Data type: Default: Read only:	Text string `''`(empty string) Never
`TasksToExecute`	Specifies the number of times the timer should execute the function specified in the `TimerFcn` property.	Data type: Value: Default Read only:	`double`Any number > 0 1 Never
`TasksExecuted`	The number of times the timer has executed `TimerFcn` since the timer was started.	Data type: Value: Default: Read only:	`double` Any number >= 0 0 Always
`TimerFcn`	Timer callback function. See Creating Timer Callback Functions for more information.	Data type: Default: Read only:	Text string, function handle, or cell array None Never
`Type`	Identifies the object type	Data type: Value: Read only:	Text string `'timer'`Always
`UserData`	User-supplied data	Data type: Default: Read only:	User-defined `[]`Never

tic, toc timerfind