Error in Serial communication between a measurement instrument and matlab via RS232

Hi I am trying to setup serial communication between my measurement instrument and matlab through RS232. I have setup the following parameters on my measurement instrument through a setup key on the front panel of the instrument:

• Communication port-RS232
• Baudrate-9600
• Parity-none
• Databits-8
• The terminator of the instrument as given in the datasheet is LF/CR

I am getting an error ' * Warning: A timeout occurred before the Terminator was reached*'. I have done some basic troubleshooting like

• putting pause(2); before fscanf(s);,
• double checking the terminator of my instrument,
• testing the RS232 cable

but the error keeps on popping everytime. Please let me know how can I resolve it.

Below given is my Matlab code.

s = serial('COM1');
set(s,'BaudRate',9600,'Parity','none','Terminator','CR');
fopen(s);
fprintf(s,'*IDN?');
out = fscanf(s);
fclose(s);
delete(s);
clear s

Answer 1

[Walter Roberson]

You indicated that the device datasheet has LF/CR but you configure CR . It would be more secure to configure for LF or CRLF for the serial port. "LF/CR" sometimes means either, but more often means both.

[Nidhi Singh]

Dear Walter

I replaced 'CR' with 'LF/CR' in the code but it's still giving the same error.

[Walter Roberson]

Time to use a different program like TeraTerm or MS-Kermit to confirm that you can communicate with the device outside of MATLAB.