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Get first free slot of resource

Add-On Required: This feature requires the MATLAB Support Package for Arduino Hardware add-on.



slot = getFreeResourceSlot(arduinoObj, resourceName) returns the first available slot or index in a continuous array allocated for the given resource. The slot count starts from 1.


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Get the free resource slot allocated to a servo object on an Arduino® Uno. This function runs only in the Create and Configure MATLAB Add-On Class of a custom Arduino add-on library.

Create a servo object.

a = arduino();
s1 = servo(a,'D7');

Get free resource slot on the servo object. In this example, the add-on object of the Arduino object is defined as obj in the Constructor. The resource name for a servo object is 'Servo'.

arduinoObj = obj.Parent;
slot1 = getFreeResourceSlot(arduinoObj,'Servo')
slot1 = 

Create a second servo object to see the free resource slot.

s2 = servo(a,'D5');
slot2 = getFreeResourceSlot(arduinoObj,'Servo')
slot2 = 

Clear the first servo object and create a third servo object to see if the first slot is cleared. Make sure to release hardware resources in your Destructor.

s3 = servo(a,'D4');
slot3 = getFreeResourceSlot(arduinoObj,'Servo')
slot3 = 

Since the slot number is 1 instead of 3, the first slot has been cleared.

Input Arguments

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Arduino object, specified as an object that is an internal variable called from within classes that derive from matlabshared.addon.LibraryBase.

Name of resource, specified as a character vector.

Output Arguments

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Slot or index number of the next free resource, returned as a double.

Version History

Introduced in R2015b