How to read data from a serial device

Hello, a MATLAB beginner here. I have a weather station which can communicate serial. I tried to communicate with it by Tera Term and it works. I referred to the manual for commands; when I type in C, it gives me the temperature. The device uses the following settings: BAUD: 9600,4800,2400, 1200, 600 or 300 Data Bits: 7 Parity: Even Stop Bits: 2 Flow Control: Hardware

I used 1,200 in Tera Term and it worked. The problem is: how do I do this in MATLAB?

Here's the code I've made so far, I tried it out but I didn't get any output.

Here's my program

%----------------------------------------

s = serial('COM1');
set(s,'BaudRate',1200);             %set BAUD
%set(s,'DataBits',7,'Name','WStation')
set(s,'DataBits',7)  
set(s,'Parity','none')              %set parity to none
set(s,'StopBits',2)                 %set stop bits to 2
set(s,'FlowControl','Hardware')
set(s,'Terminator','LF')            %set the terminator to LF
fopen(s)

%Honestly I have no idea what to put here next.
%I want to read the temperature in every 3 mins or so and to be
%able to plot it against time. Does anyone know which syntax I will %use? Thanks

fclose(s)
clear s

Thanks in advance!

Answer 1

[Nuno Martins]

Hello, Before you open the serial device you should create a log file:

logFile = fopen(logFileName, 'wt');

The command to read from a serial device is:

serial_string = fscanf(SerialObj);
date_string = datestr(now);
fprintf(logFile,[date_string ' - ' serial_string]);

If you want to read the data each 3 minutes I would recommend you to use a timer ( http://www.mathworks.com/help/techdoc/ref/timer.html )

Hope it helps.