read_input_payload.m

安捷仑的数字调制信号发生器E4438用于很多通信系统的开发过程中。本代码可以用于通过网络接口或GPIB接口向E4438下载被调制数据

%=============================================================================
%
% LTD DSP Software Schaumburg, IL.
%
% COPYRIGHT 2006 Motorola, Inc.
%
%     All Rights Reserved
%
%------------------------------- Module Name ---------------------------------
% 
% Module Name: read_input_payload.m
% 
% Original Author: Mphahlele Moruthane
% 
% Date of Origin (MM/DD/YY): 01/06/2006
% 
%-------------------------------- Revisions ----------------------------------
% 
% Person Date Comments
% 
% jan/06/2006 - moruthane - created
% 
%----------------------- Detailed Design Description -------------------------
%
% Read data from input file.  Reads input payload in ASCII hex format.
% Reshapes entire file into 1 row.  Converts each byte in the file to a
% string of 8 bytes (1 for each bit).  Returns string of bits representing
% the file to the caller.
%
% Assumptions:
%     File format consists of data in ASCII hex.
%
%     This format was chosen because the AMBE file format generated by
%     Motorola ATS "FFC" tool consists of:
%
%        Lines of 72-bit frames in ASCII hex
%          - Frame data is specified in hex, one 72-bit frame per line
%          - 18 hex digits per line representing 72 bits
%
%=============================================================================
function payload = read_input_payload(input_filename)

%=============================================================================
% Define/initialise parameters & load pre-determined data
%=============================================================================

%init payload variables
payload = [];

%=============================================================================
% Open file
%=============================================================================
fid = fopen(input_filename, 'r');

try
    %=============================================================================
    % Read data
    %=============================================================================

    % read entire ASCII file
    file_input_data = fread(fid, 'uchar');

    % make sure input data is 1 row
    [ nr, nc ] = size(file_input_data);
    ascii_input_data = reshape(file_input_data, 1, nr*nc);
    %Remove '0x' from start of data file
    if((ascii_input_data(1) == 48)&&(ascii_input_data(2) == 120))
        ascii_input_data = ascii_input_data(3:end);
    end
    % convert ASCII hex number to decimal
    g = 1;
    for h = 1:length(ascii_input_data),
       switch(ascii_input_data(h)),
          % Decimal (0-9) (0 = 48)
          case {48, 49, 50, 51, 52, 53, 54, 55, 56, 57},
             input_data(g) = ascii_input_data(h) - 48;
             g = g+1;
          % Lower-case hex digit (a-f) (a = 97)
          case {97, 98, 99, 100, 101, 102},
             input_data(g) = ascii_input_data(h) - 87;
             g = g+1;
          % Upper-case hex digit (A-F) (A = 65)
          case {65, 66, 67, 68, 69, 70},
             input_data(g) = ascii_input_data(h) - 55;
             g = g+1;
          otherwise,
                % do nothing.
       end
    end

    % convert each byte into a row of 4 bits, and append to payload
    [ nr, nc ] = size(input_data);
    for i = 1:nc,
        input_bits_str = dec2bin(input_data(i), 4);
        for j = 1:4,
            input_bits(j) = str2double(input_bits_str(j));
        end
        payload = [ payload input_bits ];
    end
catch
    % Make sure to cleanup in case of error.  (Just make sure files get closed)
%    fclose(fid);

    rethrow(lasterror);
end

%=============================================================================
% Close files
%=============================================================================
fclose(fid);