ag8753_get_data.m

%% ASCII Data Read from 8753/8720 Network Analyzers
%   
%   This is the machine generated representation of an instrument control
%   session. The instrument control session comprises all the steps you are
%   likely to take when communicating with your instrument. These steps are:
%   
%       1. Create an instrument object
%       2. Connect to the instrument
%       3. Configure properties
%       4. Write and read data
%       5. Disconnect from the instrument
% 
%   To run the instrument control session, type the name of the M-file,
%   ag8753_get_data, at the MATLAB command prompt.
% 
%   The M-file, AG8753_GET_DATA.M must be on your MATLAB PATH. For additional information 
%   on setting your MATLAB PATH, type 'help addpath' at the MATLAB command 
%   prompt.
% 
%   Example:
%       ag8753_get_data;
% 
%   See also SERIAL, GPIB, TCPIP, UDP, VISA.
% 
% 
%   Creation time: 21-Nov-2006 09:57:54
%
%   ojd - 1/12/2009
% 


%% Create a VISA-GPIB object.

instrreset;

visa_addr='GPIB5::16::INSTR';

obj1 = instrfind('Type', 'visa', 'RsrcName', visa_addr, 'Tag', '');

% Create the VISA-GPIB object if it does not exist
% otherwise use the object that was found.
if isempty(obj1)
    obj1 = visa('agilent', visa_addr);
else
    fclose(obj1);
    obj1 = obj1(1);
end

%max out buffer size for largest possible read of 1601 points
set(obj1,'InputBufferSize', 80050);

% Connect to instrument object, obj1.
fopen(obj1);

%% Communicating with instrument object, obj1.
data1 = query(obj1, 'OUTPIDEN');
fprintf(1, 'Connected to: %s\n', data1);

fwrite(obj1, 'FORM4; OPC?; SING');
opc_comp=fscanf(obj1);

%% Read data back from analyzer
fwrite(obj1, 'OUTPDATA');
data1=scanstr(obj1);

%Allocate space for data array
data=zeros(points,2);

%Convert output cell array into a standard two dimensional array
for i=1:1:points
    data(i,1)=data1{(2*i)-1};
    data(i,2)=data1{2*i};
end

%% Calculate Amplitude and Plot

%Allocate space for magnitude array
mag=zeros(points);

%Calculate Magnitude
for i=1:1:points
    mag(i)=20*log10(sqrt(data(i,1)^2+data(i,2)^2));
end

plot(mag);

%% Clean-up
% Disconnect all objects.
fclose(obj1);

% Clean up all objects.
delete(obj1);