%% AWG MATLAB ICT Send Waveform 3
% Date 10-9-2009
% ==================
% Send a waveform the an AWG using the Real format
% 
% PREREQUISITES
% ==================
% ALL MATLAB ICT Control 1 (Hello World)
% ALL MATLAB ICT Control 2
% AWGxxxx MATLAB ICT Send Waveform 1
% AWGxxxx MATLAB ICT Send Waveform 2
% ==================
%
% COMPATIBILITY
% ==================
% AWG5000, AWG5000B, AWG7000, AWG7000B
% ==================
%
% TESTED & DEVELOPED
% ==================
% Microsoft Windows XP SP3
% TekVISA 3.3.2.7
% MATLAB Version 7.9.0.529 (R2009b)
% Instrument Control Toolbox Version 2.9
% GPIB: National Instruments PCMCIA-GPIB (ni488k.sys v2.6.0f0)
% AWG5012B v3.3
% ==================
 
%% variables
visa_vendor = 'tek';
visa_address = 'GPIB0::4::INSTR';
buffer = 2 * 1024;
samples = 1200;
cycles = 2;
 
%% pre-processing
% example waveform
step = (2 * pi) / samples;
cycles = cycles * 2 * pi;
t = 0:step:cycles-step;
y = single(2*sin(t));
clear t step cycles; % free up memory
 
% example marker
% initialize marker 1 all low
m1 = zeros(1,samples,'uint8');
% set marker 1 bits 2 to 11 high
m1(2:12) = 1;
% encode marker 1 bits to bit 6
m1 = bitshift(uint8(logical(m1)),6); %check dec2bin(m1(2),8)
 
% initialize marker 2 all low
m2 = zeros(1,samples,'uint8');
% set marker 2 ouput clock = sampling rate, starting low
m2(2:2:end) = 1;
% encode marker 2 bits to bit 7
m2 = bitshift(uint8(logical(m2)),7); %check dec2bin(m2(2),8)
 
% merge markers
m = m1 + m2; %check dec2bin(m(2),8)
clear m1 m2;
 
% stitch wave data with marker data as per progammer manual
binblock = zeros(1,samples*5,'uint8'); % real uses 5 bytes per sample
for k=1:samples
    binblock((k-1)*5+1:(k-1)*5+5) = [typecast(y(k),'uint8') m(k)];
end
clear y m;
 
% build binblock header
bytes = num2str(length(binblock));
header = ['#' num2str(length(bytes)) bytes];
 
%% instrument communication
% initialize the instrument
awg = visa(visa_vendor,visa_address,'InputBufferSize',buffer, ...
    'OutputBufferSize',buffer);
fopen(awg);
 
% create waveform destination
fwrite(awg,[':wlist:waveform:new "newwave1",' num2str(samples) ',real;']);
 
% write waveform data
cmd = [':wlist:waveform:data "newwave1",' header binblock ';'];
 
bytes = length(cmd);
if buffer >= bytes
    %cmd
    fwrite(awg,cmd)
else
    awg.EOIMode = 'off';
    for i = 1:buffer:bytes-buffer
        %length(cmd(i:i+buffer-1))
        fwrite(awg,cmd(i:i+buffer-1))
    end
    awg.EOIMode = 'on';
    i=i+buffer;
    %length(cmd(i:end))
    fwrite(awg,cmd(i:end))
end
 
fclose(awg);
% delete all instrument objects
delete(instrfindall);
clear awg;
 
%% Notes
%{
% The real waveform type is not a voltage, but a scaling factor.  Maximum
% value is 1 while minimum value is -1. The resulting output voltage can be
% calculated by the following formula: my_real_wfm(sample) *
% (amplitude_setting/2) + offset_setting = output_voltage
%
% The real waveform type uses 5 bytes per sample while the integer type
% uses 2 bytes.
%
% The integer type allows for the most efficient and precise control of an
% AWG
%
% The real type allows for dynamic scaling of waveform data at run-time.
% This allows for math operations or changing bits of precision (i.e. AWG5k
% (14-bit) to/from AWG7k (8-bit), AWG7k 8-bit mode to/from AWG7k 10-bit
% mode) minimal degradation of sample data.
%}