Specify whether an asynchronous read operation is continuous or manual
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 does 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, configure ReadAsyncMode
to
continuous
.
If the device is ready to transmit data, it will do so regardless of the
ReadAsyncMode
value. Therefore, if
ReadAsyncMode
is manual
and a read
operation is not in progress, data might be lost. To guarantee that all transmitted
data is stored in the input buffer, you should configure
ReadAsyncMode
to continuous
.
To determine the amount of data available in the input buffer, use 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
.
Read only | Never |
Data type | String |
| Continuously query the device to determine if data is available to be read. |
| Manually read data from the device using the |