ButtonBoxes
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.
 2013 Buttonbox | |
| Downloads | |
|---|---|
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.
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. 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
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.
Testing Buttonbox
When pressing on the A button within the input channel tester. You will see the following ASCII code.
Adding Marker
Testing Markers (output)
Send code 1 for Button A
Button A will light up.
Send code 0 for clearing.
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
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 )
8
9while True:
10 ser.write('A1')
11 ser.flush()
12 x = ser.readline()
13 visual.TextStim(win, text=x).draw()
14
15 # black screen for 1000 ms
16 win.flip()
17
18 key = event.getKeys()
19 try:
20 if key[0]=='escape':
21 break
22 except:
23 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',handle);
13%
14% or
15%
16% to send a marker: (marker: a numeric value)
17% buttonbox(marker)
18%
19% or
20%
21% to wait for a buttonpress:
22% key = buttonbox('wait_keypress')
23%
24% to close the connection:
25% buttonbox('close',handle);
26
27persistent old_hdl % keep handle to COM object persistent
28
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
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 marker = cmd;
48 cmd = 'marker';
49end
50
51
52switch cmd
53 case 'marker'
54 if isempty(old_hdl)
55 help serial_buttonbox_common
56 error('Buttonbox not yet initialized');
57 end
58 handle = old_hdl;
59 ret = IOPort('Write', handle, uint8(marker), 1); % last argument: blocking
60 java.lang.Thread.sleep(10);
61 IOPort('Write', handle, uint8(0), 0); % last argument: blocking
62 if ret < 1
63 disp('Marker might not have been written to button box, please verify setup....?');
64 end
65 return
66 case 'open'
67 % get handle to serial device
68 handle = open_buttonbox(bb);
69 ret = handle;
70 return
71 case 'close'
72 if nargin > 0
73 handle = varargin{1};
74 else
75 handle = old_hdl;
76 end
77 fclose(handle);
78 ret = handle;
79 return
80 case 'run'
81 % read incoming data
82 if isempty(old_hdl)
83 help serial_buttonbox_common
84 error('Buttonbox not yet initialized');
85 end
86 handle = old_hdl;
87 % code proceeds below ....
88 case 'wait_keypress'
89 % read incoming data
90 if isempty(old_hdl)
91 help serial_buttonbox_common
92 error('Buttonbox not yet initialized');
93 end
94 handle = old_hdl;
95 while 1
96 % start polling for characters (indicating start of scan)
97 navailable = handle.BytesAvailable;
98 if navailable
99 data = [];
100 while navailable
101 % read incoming data
102 [newdata, cnt] = fread(handle, navailable);
103 % concatenate possible new data
104 if cnt
105 data = [data newdata(:)];
106 end
107 % check if any more data left
108 navailable = handle.BytesAvailable;
109 end
110 ret = data;
111 return
112 end
113 end %while 1
114 otherwise
115 fprintf('Unknown option %s\n',cmd);
116 ret = [];
117 return
118
119
120end
121
122%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
123% only gets here when cmd = 'run' %
124%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
125
126% Initialize output figure
127win = list_output(' ',[]);
128while 1
129 % Exit if user closed output figure
130 if ~ishandle(win)
131 return
132 end
133 % start polling for characters (indicating start of scan)
134 navailable = handle.BytesAvailable;
135 if navailable
136 data = [];
137 while navailable
138 % read incoming data
139 [newdata, cnt] = fread(handle, navailable);
140 % concatenate possible new data
141 if cnt
142 data = [data newdata(:)];
143 end
144 % check if any more data left
145 navailable = handle.BytesAvailable;
146 end
147 % output info about which button was pressed
148 for n = 1 : numel(data)
149 line = sprintf('incoming: %03d %s',data(n),char(data(n)));
150 list_output(line,win);
151 end
152 end
153 pause(0.01);
154end %while 1
155
156 function hdl = open_buttonbox(device)
157 % open handle to serial device (mini buttonbox)
158 try
159 hdl = serial(device.Device, 'Baudrate', device.BaudRate, 'DataBits', device.DataBits, 'StopBits', device.StopBits, 'Parity', device.Parity);
160 fopen(hdl);
161 catch
162 if ~isempty(old_hdl)
163 fclose(old_hdl);
164 delete(old_hdl);
165 end
166 hdl = serial(device.Device, 'Baudrate', device.BaudRate, 'DataBits', device.DataBits, 'StopBits', device.StopBits, 'Parity', device.Parity);
167 fopen(hdl);
168 end
169 old_hdl = hdl;
170
171 fprintf('Wait for device buttonbox....\n');
172 tic
173 while hdl.BytesAvailable && toc<10
174 navailable = bbox.BytesAvailable;
175 % wait for welcome message device
176 fread(hdl, navailable);
177 end
178 pause(0.5);
179
180 % while ~IOPort('BytesAvailable', hdl) && toc<10
181 % % wait for welcome message device
182 % end
183 % pause(0.5);
184
185 % clear buffer
186 %IOPort('flush', hdl);
187 IOPort('purge', hdl);
188
189 end
190
191 function win = list_output(line,win)
192 persistent ptr
193 persistent lines
194 persistent edt
195 Maxlines = 40;
196
197 if isempty(win)
198 % initialize listbox output figure
199 lines = cell(1,Maxlines);
200 [lines(1:end)]=deal({''});
201 ptr=Maxlines;
202 lines(ptr) = {'Buttonbox output:'};
203 idxs = mod(ptr:ptr+Maxlines-1,Maxlines)+1;
204
205 win = figure();
206 % initialize figure to hold output text
207 edt = uicontrol('Parent',win,'Style','ListBox','HorizontalAlignment','left', ...
208 'Max',Maxlines,'BackgroundColor',[1 1 1],'Visible','on','String',lines(idxs), ...
209 'FontSize',12,'Value',Maxlines);
210 pos = get(win,'Position');
211 set(edt,'Position',[1 1 pos(3) pos(4)]);
212 end
213 ptr = mod(ptr,Maxlines)+1; % start
214 lines{ptr} = line;
215 idxs = mod(ptr:ptr+Maxlines-1,Maxlines)+1;
216 set(edt,'String',lines(idxs),'Value',Maxlines);
217 drawnow;
218 end
219end