ButtonBoxes

File:Foto 1small.jpg

Buttonbox

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 8 bits analog outputs and three 8 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.

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
Soundkey	S / s	83 / 115
Voicekey	V / v	86 / 118

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. Press button H and A for simple mode and H 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.

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.

Python/PsychoPy

Download this site package to use the buttonbox: 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# wait for a single button press
10bb.sendMarker(val=100)    #This is your marker code, range code 1-255

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 handle = buttonbox(cmd,varargin)
  2% to initialize connection:
  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:
 12% buttonbox('run',handle);
 13%
 14% to close the connection:
 15% buttonbox('close',handle);
 16
 17persistent old_hdl  % keep handle to COM object persistent
 18
 19% set defaults
 20bb.Device    = 'COM2';
 21bb.BaudRate  = 115200;
 22bb.DataBits  = 8;
 23bb.StopBits  = 1;
 24bb.Parity    = 'none';
 25
 26if nargin < 1
 27    cmd = 'open';
 28end
 29if nargin > 1
 30    % user overwrites default settings
 31    flds = fields(varargin{1});
 32    for n = 1 : numel(flds)
 33        bb.(flds{n}) = varargin{1}.(flds{n});
 34    end
 35end
 36
 37
 38switch cmd
 39    case 'open'
 40        % get handle to serial device
 41        handle = open_buttonbox(bb);
 42        return
 43    case 'close'
 44        if nargin > 0
 45            handle = varargin{1};
 46        else
 47            handle = old_hdl;
 48        end
 49        fclose(handle);
 50        return
 51    case 'run'
 52        % read incoming data
 53        if isempty(old_hdl)
 54            help serial_buttonbox_common
 55            error('Buttonbox not yet initialized');
 56        end
 57        handle = old_hdl;
 58    otherwise
 59        fprintf('Unknown option %s\n',cmd);
 60        return
 61end
 62
 63% only gets here when cmd = 'run'
 64% Initialize output figure
 65win = list_output(' ',[]);
 66while 1
 67    % Exit if user closed output figure
 68    if ~ishandle(win)
 69        return
 70    end
 71    % start polling for characters (indicating start of scan)
 72    navailable = handle.BytesAvailable;
 73    if navailable
 74        data = [];
 75        while navailable
 76            % read incoming data
 77            [newdata, cnt] = fread(handle, navailable);
 78            % concatenate possible new data 
 79            if cnt
 80                data = [data newdata(:)];
 81            end
 82            % check if any more data left
 83            navailable = handle.BytesAvailable;
 84        end
 85        % output info about which button was pressed 
 86        for n = 1 : numel(data)
 87            line = sprintf('incoming: %03d   %s',data(n),char(data(n)));
 88            list_output(line,win);
 89        end
 90    end
 91    pause(0.01);
 92end %while 1
 93
 94    function hdl = open_buttonbox(device)
 95        % open handle to serial device (mini buttonbox)
 96        try
 97            hdl = serial(device.Device, 'Baudrate', device.BaudRate, 'DataBits', device.DataBits, 'StopBits', device.StopBits, 'Parity', device.Parity);
 98            fopen(hdl);
 99        catch
100            if ~isempty(old_hdl)
101                fclose(old_hdl);
102                delete(old_hdl);
103            end
104            hdl = serial(device.Device, 'Baudrate', device.BaudRate, 'DataBits', device.DataBits, 'StopBits', device.StopBits, 'Parity', device.Parity);
105            fopen(hdl);
106        end
107        old_hdl = hdl;
108        
109        fprintf('Wait for device buttonbox....\n');
110        tic
111        while hdl.BytesAvailable && toc<10
112            navailable = bbox.BytesAvailable;
113            % wait for welcome message device
114            fread(hdl, navailable);
115        end
116        pause(0.5);
117    end
118
119    function win = list_output(line,win)
120        persistent ptr
121        persistent lines
122        persistent edt
123        Maxlines = 40; 
124        
125        if isempty(win)
126            % initialize listbox output figure
127            lines = cell(1,Maxlines);
128            [lines(1:end)]=deal({''});
129            ptr=Maxlines;
130            lines(ptr) = {'Buttonbox output:'};
131            idxs = mod(ptr:ptr+Maxlines-1,Maxlines)+1;
132
133            win = figure();
134            % initialize figure to hold output text
135            edt = uicontrol('Parent',win,'Style','ListBox','HorizontalAlignment','left', ...
136            'Max',Maxlines,'BackgroundColor',[1 1 1],'Visible','on','String',lines(idxs), ...
137            'FontSize',12,'Value',Maxlines);
138            pos = get(win,'Position');
139            set(edt,'Position',[1 1 pos(3) pos(4)]);
140        end  
141        ptr = mod(ptr,Maxlines)+1; % start 
142        lines{ptr} = line;
143        idxs = mod(ptr:ptr+Maxlines-1,Maxlines)+1;
144        set(edt,'String',lines(idxs),'Value',Maxlines);
145        drawnow; 
146    end
147
148end

Downloads

Hardware Design

• Buttonbox 2013 Hardware Design

Software

• Code Template 2015 (Duemilanove)