Difference between revisions of "ButtonBoxes"

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 +
{{Infobox tsg
 +
| name          = Buttonbox (2018)
 +
| image          = Buttonbox_2018_1.png
 +
| caption        = 2018 Buttonbox
 +
| downloads      = {{bulleted list
 +
      | [https://surfdrive.surf.nl/files/index.php/s/PPTKCyrjLkN4XUO Buttonbox 2018]
 +
      | [https://pypi.python.org/pypi/RuSocSci RuSocSci] (Python package)
 +
  }}
 +
}}
 
{{Infobox tsg
 
{{Infobox tsg
 
| name          = Buttonbox
 
| name          = Buttonbox
Line 4: Line 13:
 
| caption        = 2013 Buttonbox
 
| caption        = 2013 Buttonbox
 
| downloads      = {{bulleted list
 
| downloads      = {{bulleted list
       | [[Buttonbox 2013 Hardware|Buttonbox 2013 Hardware Design]]
+
       | [https://surfdrive.surf.nl/files/index.php/s/72XEcu2XKSgzxjp Buttonbox 2015]
      | [[Media:BITSI_tempalte2015_duemilanove.zip|Code Template 2015 (Duemilanove)]]
 
 
       | [https://pypi.python.org/pypi/RuSocSci RuSocSci] (Python package)
 
       | [https://pypi.python.org/pypi/RuSocSci RuSocSci] (Python package)
 
   }}
 
   }}
Line 13: Line 21:
  
 
The output connector has two binary eight bit ports: input and output. The two ports can be used for responses (input) and stimulus triggers (output). Two 12 bits analog outputs and three 12 bits analog inputs. The output connector has a sound and voicekey which triggers when a amplitude reaches a threshold. By using the serial port, the BITSI can be used platform independently: it works on Windows, Linux and Mac OSX. Most programming environments and stimulus packages support serial communication.
 
The output connector has two binary eight bit ports: input and output. The two ports can be used for responses (input) and stimulus triggers (output). Two 12 bits analog outputs and three 12 bits analog inputs. The output connector has a sound and voicekey which triggers when a amplitude reaches a threshold. By using the serial port, the BITSI can be used platform independently: it works on Windows, Linux and Mac OSX. Most programming environments and stimulus packages support serial communication.
 +
 +
There is currently a [[Microsoft Windows driver issue]].
  
 
== BITSI Protocol ==
 
== BITSI Protocol ==
Line 52: Line 62:
 
===Output===
 
===Output===
  
Output knows two protocols: '''BITSI simple''' or '''BITSI extended'''. To enter a certain protocol two buttons have to be pressed when the BITSIbox is powered. '''Press button H and A for simple mode and H and B for extended mode.'''
+
Output knows two protocols: '''BITSI simple''' or '''BITSI extended'''. To enter a certain protocol two buttons have to be pressed when the BITSIbox is powered or com port opens. '''[2015]Press button H and A for simple mode and H and B for extended mode. [2018]Press button E and A for simple mode and E and B for extended mode.'''
  
 
If no button is pressed when powered it boots the last known protocol. In the simple protocol every byte sent to the BITSI over the serial port, is represented at the 8 bit output.
 
If no button is pressed when powered it boots the last known protocol. In the simple protocol every byte sent to the BITSI over the serial port, is represented at the 8 bit output.
Line 109: Line 119:
  
 
The 25 pins female connector has 8 inputs and 8 outputs, respectively 1-8 are inputs and 9-16 are outputs. Three analog input with an analog to digital convertor of 12 bit, pins 17,18,20 and 21. Two analog outputs with an digital to analog convertor of 12 bits on pins 22 and 23.
 
The 25 pins female connector has 8 inputs and 8 outputs, respectively 1-8 are inputs and 9-16 are outputs. Three analog input with an analog to digital convertor of 12 bit, pins 17,18,20 and 21. Two analog outputs with an digital to analog convertor of 12 bits on pins 22 and 23.
 +
 +
The inputs 1-8 will be pulled down from 5V to GND when the buttons are pressed. The outputs 9-16 will be pulled up from GND to 5V when the output is activated.
  
 
===Serial port===
 
===Serial port===
Line 172: Line 184:
 
* Rate must be set 115200, Parity to None, Data Bits to 8 and Stop Bits to 1, Uncheck FIFO Interrupt.
 
* Rate must be set 115200, Parity to None, Data Bits to 8 and Stop Bits to 1, Uncheck FIFO Interrupt.
  
[[File:Buttonbox1.png]]
+
[[File:Buttonbox2.png]]
  
 
'''Testing Buttonbox'''
 
'''Testing Buttonbox'''
Line 211: Line 223:
 
=== Python/PsychoPy ===
 
=== Python/PsychoPy ===
  
Download this site-package to use the buttonbox: [https://pypi.python.org/pypi/RuSocSci rusocsci]
+
Download this site-package to use the buttonbox: [https://pypi.python.org/pypi/RuSocSci rusocsci]  
 +
 
 +
or use in windows command 'pip install --upgrade rusocsci'
  
 
'''Example using buttons from the buttonbox in Python:'''
 
'''Example using buttons from the buttonbox in Python:'''
Line 275: Line 289:
 
# make a buttonbox
 
# make a buttonbox
 
ser = serial.Serial("COM2", 115200, timeout = 0.10 )
 
ser = serial.Serial("COM2", 115200, timeout = 0.10 )
 +
ser = serial.Serial("/dev/ttyUSB0", 115200, timeout = 0.10 )
  
 
while True:
 
while True:
Line 339: Line 354:
 
%
 
%
 
% to run: (receiving incoming data, check code for own purposes)
 
% to run: (receiving incoming data, check code for own purposes)
% buttonbox('run',handle);
+
% buttonbox('run');
 
%
 
%
 
% or
 
% or
 
%
 
%
% to send a marker: (marker: a numeric value)
+
% to send a marker: (marker: a numeric value; Fs: sampling frequency device)
% buttonbox(marker)
+
% buttonbox(marker,Fs)
 
%
 
%
 
% or
 
% or
Line 353: Line 368:
 
%
 
%
 
% to close the connection:
 
% to close the connection:
% buttonbox('close',handle);
+
% buttonbox('close');  
 
 
persistent old_hdl  % keep handle to COM object persistent
 
  
 +
persistent old_hdl  % keep handle to COM object persistent
 
% set defaults
 
% set defaults
 
bb.Device    = 'COM2';
 
bb.Device    = 'COM2';
Line 362: Line 376:
 
bb.DataBits  = 8;
 
bb.DataBits  = 8;
 
bb.StopBits  = 1;
 
bb.StopBits  = 1;
bb.Parity    = 'none';
+
bb.Parity    = 'none';  
  
 
if nargin < 1
 
if nargin < 1
 
   cmd = 'open';
 
   cmd = 'open';
 
end
 
end
if nargin > 1
+
if nargin > 1 && isstruct(varargin{1})
 
   % user overwrites default settings
 
   % user overwrites default settings
 
   flds = fields(varargin{1});
 
   flds = fields(varargin{1});
Line 375: Line 389:
 
end
 
end
 
if nargin==1 && isnumeric(cmd)
 
if nargin==1 && isnumeric(cmd)
 +
  error('Please also specify acquisition sampling frequency of device that receives the marker');
 +
end
 +
if nargin > 1 && isnumeric(cmd)
 
   marker = cmd;
 
   marker = cmd;
 
   cmd = 'marker';
 
   cmd = 'marker';
 +
  Fs = varargin{1};
 
end
 
end
  
 +
if ~any(strcmp(cmd,{'open','close'}))
 +
  if isempty(old_hdl)
 +
      help serial_buttonbox_common
 +
      error('Buttonbox not yet initialized');
 +
  end
 +
  handle = old_hdl;
 +
end
  
 
switch cmd
 
switch cmd
 
   case 'marker'
 
   case 'marker'
       if isempty(old_hdl)
+
       fwrite(handle, uint8(marker));%IOPort('Write', handle, uint8(marker), 1); % last argument: blocking
        help serial_buttonbox_common
+
       WaitSecs(2/Fs);
        error('Buttonbox not yet initialized');
+
       fwrite(handle, uint8(0));%IOPort('Write', handle, uint8(0), 0); % last argument: blocking
      end
 
      handle = old_hdl;
 
      ret = IOPort('Write', handle, uint8(marker), 1); % last argument: blocking
 
       java.lang.Thread.sleep(10);
 
       IOPort('Write', handle, uint8(0), 0); % last argument: blocking
 
      if ret < 1
 
        disp('Marker might not have been written to button box, please verify setup....?');
 
      end     
 
 
       return
 
       return
 
   case 'clear'
 
   case 'clear'
       if isempty(old_hdl)
+
       while(handle.BytesAvailable)
         help serial_buttonbox_common
+
         fread(handle, 1);
        error('Buttonbox not yet initialized');
+
       end    
       end
 
      handle = old_hdl;
 
      IOPort('purge', handle);
 
 
       ret = []; % meaningless
 
       ret = []; % meaningless
 
       return
 
       return
Line 409: Line 423:
 
       return
 
       return
 
   case 'close'
 
   case 'close'
       if nargin > 0
+
       if nargin > 1
 
         handle = varargin{1};
 
         handle = varargin{1};
 
       else
 
       else
Line 415: Line 429:
 
       end
 
       end
 
       fclose(handle);
 
       fclose(handle);
       ret = handle;
+
      delete(handle);
 +
       ret = [];
 
       return
 
       return
 
   case 'run'
 
   case 'run'
 
       % read incoming data
 
       % read incoming data
      if isempty(old_hdl)
 
        help serial_buttonbox_common
 
        error('Buttonbox not yet initialized');
 
      end
 
      handle = old_hdl;
 
 
       % code proceeds below ....
 
       % code proceeds below ....
 
   case 'wait_keypress'
 
   case 'wait_keypress'
       % read incoming data
+
       % start polling for characters (indicating start of scan)
      if isempty(old_hdl)
+
      while(1)
        help serial_buttonbox_common
+
         data = [];
        error('Buttonbox not yet initialized');
+
        while handle.BytesAvailable
      end
+
            navailable = handle.BytesAvailable;
      handle = old_hdl;
+
             % read incoming data
      while 1
+
            [newdata, cnt] = fread(handle, navailable);
        % start polling for characters (indicating start of scan)
+
            % concatenate possible new data
         navailable = handle.BytesAvailable;
+
            if cnt
        if navailable
+
              data = [data newdata(:)];
            data = [];
 
             while navailable
 
              % read incoming data
 
              [newdata, cnt] = fread(handle, navailable);
 
              % concatenate possible new data
 
              if cnt
 
                  data = [data newdata(:)];
 
              end
 
              % check if any more data left
 
              navailable = handle.BytesAvailable;
 
 
             end
 
             end
 +
        end
 +
        if ~isempty(data)
 
             ret = data;
 
             ret = data;
 
             return
 
             return
 
         end
 
         end
       end %while 1
+
       end
 
   otherwise
 
   otherwise
 
       fprintf('Unknown option %s\n',cmd);
 
       fprintf('Unknown option %s\n',cmd);
 
       ret = [];
 
       ret = [];
       return
+
       return          
     
+
end  
     
 
end
 
  
 
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 
% only gets here when cmd = 'run' %
 
% only gets here when cmd = 'run' %
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%  
 
 
 
% Initialize output figure
 
% Initialize output figure
 
win = list_output(' ',[]);
 
win = list_output(' ',[]);
Line 491: Line 490:
 
   end
 
   end
 
   pause(0.01);
 
   pause(0.01);
end %while 1
+
end %while 1  
 +
 
 +
 
  
 
   function hdl = open_buttonbox(device)
 
   function hdl = open_buttonbox(device)
       % open handle to serial device (mini buttonbox)
+
       % open handle to serial device (mini buttonbox)     WaitSecs(0.002); % just to load mex-file into memory
 
       try
 
       try
 
         hdl = serial(device.Device, 'Baudrate', device.BaudRate, 'DataBits', device.DataBits, 'StopBits', device.StopBits, 'Parity', device.Parity);
 
         hdl = serial(device.Device, 'Baudrate', device.BaudRate, 'DataBits', device.DataBits, 'StopBits', device.StopBits, 'Parity', device.Parity);
Line 506: Line 507:
 
         fopen(hdl);
 
         fopen(hdl);
 
       end
 
       end
       old_hdl = hdl;
+
       old_hdl = hdl;    
     
 
 
       fprintf('Wait for device buttonbox....\n');
 
       fprintf('Wait for device buttonbox....\n');
 
       tic
 
       tic
Line 515: Line 515:
 
         fread(hdl, navailable);
 
         fread(hdl, navailable);
 
       end
 
       end
       pause(0.5);
+
       pause(0.5);    
     
+
   end  
      % while ~IOPort('BytesAvailable', hdl) && toc<10
 
      % % wait for welcome message device
 
      % end
 
      % pause(0.5);
 
     
 
      % clear buffer
 
      %IOPort('flush', hdl);
 
      IOPort('purge', hdl);
 
     
 
   end
 
  
 
   function win = list_output(line,win)
 
   function win = list_output(line,win)
Line 532: Line 522:
 
       persistent lines
 
       persistent lines
 
       persistent edt
 
       persistent edt
       Maxlines = 40;
+
       Maxlines = 40;    
     
 
 
       if isempty(win)
 
       if isempty(win)
 
         % initialize listbox output figure
 
         % initialize listbox output figure
Line 540: Line 529:
 
         ptr=Maxlines;
 
         ptr=Maxlines;
 
         lines(ptr) = {'Buttonbox output:'};
 
         lines(ptr) = {'Buttonbox output:'};
         idxs = mod(ptr:ptr+Maxlines-1,Maxlines)+1;
+
         idxs = mod(ptr:ptr+Maxlines-1,Maxlines)+1;        
       
 
 
         win = figure();
 
         win = figure();
 
         % initialize figure to hold output text
 
         % initialize figure to hold output text
Line 555: Line 543:
 
       set(edt,'String',lines(idxs),'Value',Maxlines);
 
       set(edt,'String',lines(idxs),'Value',Maxlines);
 
       drawnow;
 
       drawnow;
   end
+
   end  
 
+
end
end</syntaxhighlight>
+
end</syntaxhighlight>

Revision as of 13:50, 7 August 2019

Buttonbox (2018)
Buttonbox 2018 1.png
2018 Buttonbox
Downloads
Buttonbox
Buttonbox 03s.png
2013 Buttonbox
Downloads

The buttonbox is used for time accurate(1ms) button press registration. We use it to register buttonpresses, soundkey, voicekey signals and to send tone onset, analog output, triggers with the BITSI protocol. It is suitable for Behavioral, EEG, MEG, and fMRI experiments. The buttonbox is connected to a computer with a usb connection.

The output connector has two binary eight bit ports: input and output. The two ports can be used for responses (input) and stimulus triggers (output). Two 12 bits analog outputs and three 12 bits analog inputs. The output connector has a sound and voicekey which triggers when a amplitude reaches a threshold. By using the serial port, the BITSI can be used platform independently: it works on Windows, Linux and Mac OSX. Most programming environments and stimulus packages support serial communication.

There is currently a Microsoft Windows driver issue.

BITSI Protocol

BITSI stands for Bits to Serial Interface. Because the BITSI is designed to interface both in- and output signals, the 'protocol' is asymmetric: the input and output protocols differ.

Input

The input port can be used to interface eight buttons maximally. Button presses are translated to serial output characters/bytes according to the following table:

BITSI Simple
Signal/Button ASCII (rise/fall) Code (rise/fall)
1 A / a 65 / 97
2 B / b 66 / 98
3 C / c 67 / 99
4 D / d 68 / 100
5 E / e 69 / 101
6 F / f 70 / 102
7 G / g 71 / 103
8 H / h 72 / 104

This means that when signal 1 gets active(button press), a capital A will be sent to the serial port. A lowercase 'a' will be sent when the signal is deactivated(button release). Mechanical buttons can be connected directly.

Output

Output knows two protocols: BITSI simple or BITSI extended. To enter a certain protocol two buttons have to be pressed when the BITSIbox is powered or com port opens. [2015]Press button H and A for simple mode and H and B for extended mode. [2018]Press button E and A for simple mode and E and B for extended mode.

If no button is pressed when powered it boots the last known protocol. In the simple protocol every byte sent to the BITSI over the serial port, is represented at the 8 bit output.

The extended protocol uses two bytes(or two characters), this combination can access two analog outputs and a tone generator. The first byte selects the output. The second byte determines the value written to this output.

BITSI Extended
Function Byte 1 (ASCII/code) Byte 2
Marker Out M / 77 Marker Value
Pulse Out P / 80 Marker Value
Pulse Time X / 88 ms before pulse reset
Analog Out 1 Y / 89 Analog Output Value
Analog Out 2 Z / 90 Analog Output Value
Tone T / 84 Start Tone
Detect Sound D / S / 83
Detect Voice D / V / 83
Calibrate Sound C / S
Calibrate Voice C / V
Analog In 1 A / 1
Analog In 2 A / 2
Analog In 3 A / 3
Analog In 4 A / 4
LEDs Off L / X
LEDs Input L / I
LEDs Output L / O

Port Settings

Trigger port

Schematic view of the 25 pins connector

The 25 pins female connector has 8 inputs and 8 outputs, respectively 1-8 are inputs and 9-16 are outputs. Three analog input with an analog to digital convertor of 12 bit, pins 17,18,20 and 21. Two analog outputs with an digital to analog convertor of 12 bits on pins 22 and 23.

The inputs 1-8 will be pulled down from 5V to GND when the buttons are pressed. The outputs 9-16 will be pulled up from GND to 5V when the output is activated.

Serial port

Our hardware design allows to be connected to the computers USB and emulates a serial communication Port.

Baudrate 115200
Parity None
Data bits 8
Stop bits 1
Flow control None

USB-Com port

1.Connect the BITSIbox to your computer using the USB cable.

2.When you connect the BITSIbox, Windows should initiate the driver installation process (if you haven't used the computer with an BITSIbox board before).

3.On Windows Vista/7, the driver should be automatically downloaded and installed.

4.On Windows XP, the Add New Hardware wizard will open:

  • When asked Can Windows connect to Windows Update to search for software? select No, not this time. Click next.
  • Select Install from a list or specified location (Advanced) and click next.
  • Make sure that Search for the best driver in these locations is checked; uncheck Search removable media; check Include this location in the search and browse to the c:/beheer/arduino/drivers directory.
  • The wizard will search for the driver and then tell you that a "USB Serial Converter" was found. Click finish.
  • The new hardware wizard will appear again. Go through the same steps and select the same options and location to search. This time, a "USB Serial Port" will be found.

How to Check the Com Port settings(important!)

  • From the Start menu, open the Control Panel.
  • From the control panel, open the System window.
  • From the system properties window, go to the Hardware tab and click the Device Manager button.
  • From the Device Manager window, click Ports (Com&LPT). You should now be able to see which Com Port the USB adapter is assigned to.
  • If the Com Port is 10 or higher, you will have to change it to a lower port.
  • From the Device Manager window, click on USB Serial Port (Com#). Click the Port Settings tab of the USB Serial Port Properties window, and then click the Advanced button.
  • In the Advanced Settings window, use the scroll input to select a Com Port (select 10 or lower). Change Receive (bytes) and Transmit (bytes) to 64. Change the Latency Timer to 1.
  • Click the OK button.

Always connect the usb device to the same port and your settings will be remembered.

Software Settings

Neurobs Presentation

The experiment files needs a few settings for the device to work:

  • In the settings tab: port -> input port -> 1 must be the device that identifies itself as "Arduino Uno" in the device manager. Note that the port must have a number not higher than 10 (COM1-COM10). Use re-enumerate if it is higher.
  • Rate must be set 115200, Parity to None, Data Bits to 8 and Stop Bits to 1, Uncheck FIFO Interrupt.

Buttonbox2.png

Testing Buttonbox

When pressing on the A button within the input channel tester. You will see the following ASCII code.

Testbuttonbox.png

Adding Marker

Output buttonbox1.png

Testing Markers (output)

Send code 1 for Button A

Output buttonbox2.png

Button A will light up.

ButtonboxledA.png

Send code 0 for clearing.

Output buttonbox3.png

Example PCL code you can program a handle to send a marker:

#handle:
output_port OutputPort = output_port_manager.get_port( 1 );

Example to send a marker:

OutputPort.send_code(100); #create a marker


for more information see chapter 8 in the presentation course by clicking here

Python/PsychoPy

Download this site-package to use the buttonbox: rusocsci

or use in windows command 'pip install --upgrade rusocsci'

Example using buttons from the buttonbox in Python:

 1#!/usr/bin/env python
 2
 3# import the rusocsci.buttonbox module
 4from rusocsci import buttonbox 
 5
 6# make a buttonbox
 7bb = buttonbox.Buttonbox()
 8
 9# wait for a single button press
10b = bb.waitButtons()
11
12# print the button pressed
13print("b: {}".format(b))

Example using markers with the buttonbox in Python:

 1#!/usr/bin/env python
 2
 3# import the rusocsci.buttonbox module
 4from rusocsci import buttonbox 
 5
 6# make a buttonbox
 7bb = buttonbox.Buttonbox()
 8
 9# send a marker
10bb.sendMarker(val=100)    #This is your marker code, range code 1-255

Example using BITSI extended in Python:

 1#!/usr/bin/env python
 2
 3# import the rusocsci.buttonbox module
 4from rusocsci import buttonbox 
 5
 6# make a buttonbox
 7bb = buttonbox.Buttonbox()
 8
 9# select a function
10bb.sendMarker(val=(ord(X)))    #select pulse time
11bb.sendMarker(val=2)           #set time of dureation pulse to 2ms
12
13bb.sendMarker(val=(ord(M)))    #select marker out
14bb.sendMarker(val=115)           #set marker value 115

Example using BITSI extended analog read in Python:

 1#!/usr/bin/env python
 2
 3# import the rusocsci.buttonbox module
 4import serial
 5
 6# make a buttonbox
 7ser = serial.Serial("COM2", 115200, timeout = 0.10 )
 8ser = serial.Serial("/dev/ttyUSB0", 115200, timeout = 0.10 )
 9
10while True:
11	ser.write('A1')
12	ser.flush()
13	x = ser.readline()
14	visual.TextStim(win, text=x).draw()
15
16	# black screen for 1000 ms
17	win.flip()
18
19	key = event.getKeys()
20	try:
21		if key[0]=='escape':
22			break
23	except:
24		continue


Example using the Buttonbox in PsychoPy:

 1#!/usr/bin/env python
 2
 3# import psychopy and rusocsci
 4from psychopy import core, visual 
 5from rusocsci import buttonbox
 6
 7## Setup Section
 8win = visual.Window(monitor="testMonitor")
 9bb = buttonbox.Buttonbox()
10text = visual.TextStim(win, "Press a button on the buttonbox")
11
12## Experiment Section
13# show text
14text.draw()
15win.flip()
16# wait for response
17b = bb.waitButtons()
18# show response
19text.setText("you pressed: {}".format(b))
20text.draw()
21win.flip()
22core.wait(5)
23
24## Cleanup Section
25core.quit()

For more documentation click here: http://pythonhosted.org//RuSocSci/index.html

Matlab

  1function ret = buttonbox(cmd,varargin)
  2% to initialize connection: (omit 2nd argument if defaults apply)
  3%    define settings as structure with fields:
  4%       bb.Device    = 'COM2';
  5%       bb.BaudRate  = 115200;
  6%       bb.DataBits  = 8;
  7%       bb.StopBits  = 1;
  8%       bb.Parity    = 'none';
  9% handle = buttonbox('open',bb)
 10%
 11% to run: (receiving incoming data, check code for own purposes)
 12% buttonbox('run');
 13%
 14% or
 15%
 16% to send a marker: (marker: a numeric value; Fs: sampling frequency device)
 17% buttonbox(marker,Fs)
 18%
 19% or
 20%
 21% to wait for a buttonpress:
 22% buttonbox('clear'); (make sure buttonbox buffer is emptied)
 23% key = buttonbox('wait_keypress')
 24%
 25% to close the connection:
 26% buttonbox('close'); 
 27
 28persistent old_hdl  % keep handle to COM object persistent 
 29% set defaults
 30bb.Device    = 'COM2';
 31bb.BaudRate  = 115200;
 32bb.DataBits  = 8;
 33bb.StopBits  = 1;
 34bb.Parity    = 'none'; 
 35
 36if nargin < 1
 37   cmd = 'open';
 38end
 39if nargin > 1 && isstruct(varargin{1})
 40   % user overwrites default settings
 41   flds = fields(varargin{1});
 42   for n = 1 : numel(flds)
 43      bb.(flds{n}) = varargin{1}.(flds{n});
 44   end
 45end
 46if nargin==1 && isnumeric(cmd)
 47   error('Please also specify acquisition sampling frequency of device that receives the marker');
 48end
 49if nargin > 1 && isnumeric(cmd)
 50   marker = cmd;
 51   cmd = 'marker';
 52   Fs = varargin{1};
 53end
 54
 55if ~any(strcmp(cmd,{'open','close'}))
 56   if isempty(old_hdl)
 57      help serial_buttonbox_common
 58      error('Buttonbox not yet initialized');
 59   end
 60   handle = old_hdl;
 61end
 62
 63switch cmd
 64   case 'marker'
 65      fwrite(handle, uint8(marker));%IOPort('Write', handle, uint8(marker), 1); % last argument: blocking
 66      WaitSecs(2/Fs);
 67      fwrite(handle, uint8(0));%IOPort('Write', handle, uint8(0), 0); % last argument: blocking
 68      return
 69   case 'clear'
 70      while(handle.BytesAvailable)
 71         fread(handle, 1);
 72      end      
 73      ret = []; % meaningless
 74      return
 75   case 'open'
 76      % get handle to serial device
 77      handle = open_buttonbox(bb);
 78      ret = handle;
 79      return
 80   case 'close'
 81      if nargin > 1
 82         handle = varargin{1};
 83      else
 84         handle = old_hdl;
 85      end
 86      fclose(handle);
 87      delete(handle);
 88      ret = [];
 89      return
 90   case 'run'
 91      % read incoming data
 92      % code proceeds below ....
 93   case 'wait_keypress'
 94      % start polling for characters (indicating start of scan)
 95      while(1)
 96         data = [];
 97         while handle.BytesAvailable
 98            navailable = handle.BytesAvailable;
 99            % read incoming data
100            [newdata, cnt] = fread(handle, navailable);
101            % concatenate possible new data
102            if cnt
103               data = [data newdata(:)];
104            end
105         end
106         if ~isempty(data)
107            ret = data;
108            return
109         end
110      end
111   otherwise
112      fprintf('Unknown option %s\n',cmd);
113      ret = [];
114      return            
115end 
116
117%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
118% only gets here when cmd = 'run' %
119%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% 
120% Initialize output figure
121win = list_output(' ',[]);
122while 1
123   % Exit if user closed output figure
124   if ~ishandle(win)
125      return
126   end
127   % start polling for characters (indicating start of scan)
128   navailable = handle.BytesAvailable;
129   if navailable
130      data = [];
131      while navailable
132         % read incoming data
133         [newdata, cnt] = fread(handle, navailable);
134         % concatenate possible new data
135         if cnt
136            data = [data newdata(:)];
137         end
138         % check if any more data left
139         navailable = handle.BytesAvailable;
140      end
141      % output info about which button was pressed
142      for n = 1 : numel(data)
143         line = sprintf('incoming: %03d   %s',data(n),char(data(n)));
144         list_output(line,win);
145      end
146   end
147   pause(0.01);
148end %while 1 
149
150
151
152   function hdl = open_buttonbox(device)
153      % open handle to serial device (mini buttonbox)      WaitSecs(0.002); % just to load mex-file into memory
154      try
155         hdl = serial(device.Device, 'Baudrate', device.BaudRate, 'DataBits', device.DataBits, 'StopBits', device.StopBits, 'Parity', device.Parity);
156         fopen(hdl);
157      catch
158         if ~isempty(old_hdl)
159            fclose(old_hdl);
160            delete(old_hdl);
161         end
162         hdl = serial(device.Device, 'Baudrate', device.BaudRate, 'DataBits', device.DataBits, 'StopBits', device.StopBits, 'Parity', device.Parity);
163         fopen(hdl);
164      end
165      old_hdl = hdl;      
166      fprintf('Wait for device buttonbox....\n');
167      tic
168      while hdl.BytesAvailable && toc<10
169         navailable = bbox.BytesAvailable;
170         % wait for welcome message device
171         fread(hdl, navailable);
172      end
173      pause(0.5);      
174   end 
175
176   function win = list_output(line,win)
177      persistent ptr
178      persistent lines
179      persistent edt
180      Maxlines = 40;      
181      if isempty(win)
182         % initialize listbox output figure
183         lines = cell(1,Maxlines);
184         [lines(1:end)]=deal({''});
185         ptr=Maxlines;
186         lines(ptr) = {'Buttonbox output:'};
187         idxs = mod(ptr:ptr+Maxlines-1,Maxlines)+1;         
188         win = figure();
189         % initialize figure to hold output text
190         edt = uicontrol('Parent',win,'Style','ListBox','HorizontalAlignment','left', ...
191            'Max',Maxlines,'BackgroundColor',[1 1 1],'Visible','on','String',lines(idxs), ...
192            'FontSize',12,'Value',Maxlines);
193         pos = get(win,'Position');
194         set(edt,'Position',[1 1 pos(3) pos(4)]);
195      end
196      ptr = mod(ptr,Maxlines)+1; % start
197      lines{ptr} = line;
198      idxs = mod(ptr:ptr+Maxlines-1,Maxlines)+1;
199      set(edt,'String',lines(idxs),'Value',Maxlines);
200      drawnow;
201   end 
202end
203 end