How can I empty the serial port buffer in MATLAB without using the Instrument Control Toolbox?

I am using core MATLAB to communicate via the serial port (not the Instrument Control Toolbox).

I would like to clear the serial port (RS-232) buffer from MATLAB.

Answer 1

[MathWorks Support Team]

One way to clear the contents of the serial port buffer is to do a simple

fscanf(serialobj)

to read everything in the buffer until the first terminator, which is 'LF' by default. If there is a terminator in the buffer before the last character of the buffer then the previous code will not clear the buffer completely.

Alternatively, you can read the available bytes in the buffer of the serialobj

and use the following code:

fread(serialobj, serialobj.BytesAvailable)

to read all the contents of the buffer. It should be noted that FREAD will return data in the binary format (as opposed to ASCII).

Disconnecting and then reconnecting to the serial object via FCLOSE and FOPEN will also flush the serial buffer. However this approach is computationally much less efficient than the solutions above.