External Interfaces

ReadAsyncMode

Specify whether an asynchronous read operation is continuous or manual

Description

You can configure ReadAsyncMode to be continuous or manual. If ReadAsyncMode is continuous, the serial port object continuously queries the device to determine if data is available to be read. If data is available, it is automatically read and stored in the input buffer. If issued, the readasync function is ignored.

If ReadAsyncMode is manual, the object will not query the device to determine if data is available to be read. Instead, you must manually issue the readasync function to perform an asynchronous read operation. Because readasync checks for the terminator, this function can be slow. To increase speed, you should configure ReadAsyncMode to continuous.

Note    If the device is ready to transmit data, then it will do so regardless of the ReadAsyncMode value. Therefore, if ReadAsyncMode is manual and a read operation is not in progress, then data might be lost. To guarantee that all transmitted data is stored in the input buffer, you should configure ReadAsyncMode to continuous.

You can determine the amount of data available in the input buffer with the BytesAvailable property. For either ReadAsyncMode value, you can bring data into the MATLAB workspace with one of the synchronous read functions such as fscanf, fgetl, fgets, or fread.

Characteristics

Read only	Never
Data type	String

Values

{continuous}	Continuously query the device to determine if data is available to be read.
manual	Manually read data from the device using the readasync function.

See Also

Functions

fgetl, fgets, fread, fscanf, readasync

Properties

BytesAvailable, InputBufferSize

Port

RecordDetail

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