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(To be removed) Stop asynchronous read and write operations

This serial object function will be removed in a future release. Use serialport object functions instead. For more information on updating your code, see Compatibility Considerations.




stopasync(obj) stops any asynchronous read or write operation that is in progress for the serial port object, obj.


You can write data asynchronously using the fprintf or fwrite function. You can read data asynchronously using the readasync function, or by configuring the ReadAsyncMode property to continuous. In-progress asynchronous operations are indicated by the TransferStatus property.

If obj is an array of serial port objects and one of the objects cannot be stopped, the remaining objects in the array are stopped and a warning is returned. After an object stops:

  • Its TransferStatus property is configured to idle.

  • Its ReadAsyncMode property is configured to manual.

  • The data in its output buffer is flushed.

Data in the input buffer is not flushed. You can return this data to the MATLAB® workspace using any of the synchronous read functions. If you execute the readasync function, or configure the ReadAsyncMode property to continuous, then the new data is appended to the existing data in the input buffer.

Version History

Introduced before R2006a

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Not recommended starting in R2021a

See Also