ReadAsyncMode - Specify whether asynchronous read operation is continuous or manual

Description

You can configure ReadAsyncMode to be continuous or manual. If ReadAsyncMode is continuous, the object continuously queries the instrument 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 instrument 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 instrument 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 can 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

Usage	Serial port, TCPIP, UDP, VISA-serial
Read only	Never
Data type	String

Values

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

See Also

Functions

fgetl, fgets, fread, fscanf, readasync

Properties

BytesAvailable, InputBufferSize

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