plx_event_ts

 plx_event_ts(filename, channel) Read event timestamps from a .plx file

 [n, ts, sv] = plx_event_ts(filename, channel)

 INPUT:
   filename - if empty string, will use File Open dialog
   channel - 1-based external channel number
             strobed channel has channel number 257  
 OUTPUT:
   n - number of timestamps
   ts - array of timestamps 
   sv - array of strobed event values (filled only if channel is 257)

0001 function [n, ts, sv] = plx_event_ts(filename, ch)
0002 % plx_event_ts(filename, channel) Read event timestamps from a .plx file
0003 %
0004 % [n, ts, sv] = plx_event_ts(filename, channel)
0005 %
0006 % INPUT:
0007 %   filename - if empty string, will use File Open dialog
0008 %   channel - 1-based external channel number
0009 %             strobed channel has channel number 257
0010 % OUTPUT:
0011 %   n - number of timestamps
0012 %   ts - array of timestamps
0013 %   sv - array of strobed event values (filled only if channel is 257)
0014 
0015 if(nargin ~= 2)
0016    disp('2 input arguments are required')
0017    return
0018 end
0019 
0020 n = 0;
0021 ts = 0;
0022 sv = 0;
0023 
0024 if(isempty(filename))
0025    [fname, pathname] = uigetfile('*.plx', 'Select a plx file');
0026     filename = strcat(pathname, fname);
0027 end
0028 
0029 fid = fopen(filename, 'r');
0030 if(fid == -1)
0031     disp('cannot open file');
0032    return
0033 end
0034 
0035 disp(strcat('file = ', filename));
0036 
0037 % read file header
0038 header = fread(fid, 64, 'int32');
0039 freq = header(35);  % frequency
0040 ndsp = header(36);  % number of dsp channels
0041 nevents = header(37); % number of external events
0042 nslow = header(38);  % number of slow channels
0043 npw = header(39);  % number of points in wave
0044 npr = header(40);  % number of points before threshold
0045 tscounts = fread(fid, [5, 130], 'int32');
0046 wfcounts = fread(fid, [5, 130], 'int32');
0047 evcounts = fread(fid, [1, 512], 'int32');
0048 
0049 % skip variable headers
0050 fseek(fid, 1020*ndsp + 296*nevents + 296*nslow, 'cof');
0051 
0052 % read the data
0053 record = 0;
0054 while feof(fid) == 0
0055     type = fread(fid, 1, 'int16');
0056     upperbyte = fread(fid, 1, 'int16');
0057     timestamp = fread(fid, 1, 'int32');
0058     channel = fread(fid, 1, 'int16');
0059     unit = fread(fid, 1, 'int16');
0060     nwf = fread(fid, 1, 'int16');
0061     nwords = fread(fid, 1, 'int16');
0062     toread = nwords;
0063     if toread > 0
0064       wf = fread(fid, toread, 'int16');
0065     end
0066        if type == 4
0067          if channel == ch 
0068                  n = n + 1;
0069                  ts(n) = timestamp;
0070                 sv(n) = unit;
0071            end
0072        end
0073    
0074    record = record + 1;
0075    if feof(fid) == 1
0076       break
0077    end
0078    
0079 end
0080 disp(strcat('number of timestamps = ', num2str(n)));
0081 
0082 fclose(fid);