plx_ts

 plx_ts(filename, channel, unit): Read spike timestamps from a .plx file

 [n, ts] = plx_ts(filename, channel, unit)

 INPUT:
   filename - if empty string, will use File Open dialog
   channel - 1-based channel number
   unit  - unit number (0- invalid, 1-4 valid)
 OUTPUT:
   n - number of timestamps
   ts - array of timestamps (in seconds)

0001 function [n, ts] = plx_ts(filename, ch, u)
0002 % plx_ts(filename, channel, unit): Read spike timestamps from a .plx file
0003 %
0004 % [n, ts] = plx_ts(filename, channel, unit)
0005 %
0006 % INPUT:
0007 %   filename - if empty string, will use File Open dialog
0008 %   channel - 1-based channel number
0009 %   unit  - unit number (0- invalid, 1-4 valid)
0010 % OUTPUT:
0011 %   n - number of timestamps
0012 %   ts - array of timestamps (in seconds)
0013 
0014 if(nargin ~= 3)
0015    disp('3 input arguments are required')
0016    return
0017 end
0018 
0019 n = 0;
0020 ts = 0;
0021 if(isempty(filename))
0022    [fname, pathname] = uigetfile('*.plx', 'Select a plx file');
0023     filename = strcat(pathname, fname);
0024 end
0025 
0026 fid = fopen(filename, 'r');
0027 if(fid == -1)
0028     disp('cannot open file');
0029    return
0030 end
0031 
0032 disp(strcat('file = ', filename));
0033 
0034 % read file header
0035 header = fread(fid, 64, 'int32');
0036 freq = header(35);  % frequency
0037 ndsp = header(36);  % number of dsp channels
0038 nevents = header(37); % number of external events
0039 nslow = header(38);  % number of slow channels
0040 npw = header(39);  % number of points in wave
0041 npr = header(40);  % number of points before threshold
0042 tscounts = fread(fid, [5, 130], 'int32');
0043 wfcounts = fread(fid, [5, 130], 'int32');
0044 evcounts = fread(fid, [1, 512], 'int32');
0045 
0046 % skip variable headers
0047 fseek(fid, 1020*ndsp + 296*nevents + 296*nslow, 'cof');
0048 
0049 % read the data
0050 record = 0;
0051 while feof(fid) == 0
0052     type = fread(fid, 1, 'int16');
0053     upperbyte = fread(fid, 1, 'int16');
0054     timestamp = fread(fid, 1, 'int32');
0055     channel = fread(fid, 1, 'int16');
0056     unit = fread(fid, 1, 'int16');
0057     nwf = fread(fid, 1, 'int16');
0058     nwords = fread(fid, 1, 'int16');
0059     toread = nwords;
0060     if toread > 0
0061       wf = fread(fid, toread, 'int16');
0062     end
0063        if type == 1
0064          if channel == ch 
0065             if unit == u
0066                  n = n + 1;
0067                  ts(n) = timestamp/freq;
0068             end
0069            end
0070        end
0071    
0072    record = record + 1;
0073    if feof(fid) == 1
0074       break
0075    end
0076    
0077 end
0078 disp(strcat('number of timestamps = ', num2str(n)));
0079 
0080 fclose(fid);