ButtonBoxes
 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.
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% buttonbox('clear'); (make sure buttonbox buffer is emptied)
23% key = buttonbox('wait_keypress')
24%
25% to close the connection:
26% buttonbox('close',handle);
27
28persistent old_hdl % keep handle to COM object persistent
29
30% set defaults
31bb.Device = 'COM2';
32bb.BaudRate = 115200;
33bb.DataBits = 8;
34bb.StopBits = 1;
35bb.Parity = 'none';
36
37if nargin < 1
38 cmd = 'open';
39end
40if nargin > 1
41 % user overwrites default settings
42 flds = fields(varargin{1});
43 for n = 1 : numel(flds)
44 bb.(flds{n}) = varargin{1}.(flds{n});
45 end
46end
47if nargin==1 && isnumeric(cmd)
48 marker = cmd;
49 cmd = 'marker';
50end
51
52
53switch cmd
54 case 'marker'
55 if isempty(old_hdl)
56 help serial_buttonbox_common
57 error('Buttonbox not yet initialized');
58 end
59 handle = old_hdl;
60 ret = IOPort('Write', handle, uint8(marker), 1); % last argument: blocking
61 java.lang.Thread.sleep(10);
62 IOPort('Write', handle, uint8(0), 0); % last argument: blocking
63 if ret < 1
64 disp('Marker might not have been written to button box, please verify setup....?');
65 end
66 return
67 case 'clear'
68 if isempty(old_hdl)
69 help serial_buttonbox_common
70 error('Buttonbox not yet initialized');
71 end
72 handle = old_hdl;
73 IOPort('purge', handle);
74 ret = []; % meaningless
75 return
76 case 'open'
77 % get handle to serial device
78 handle = open_buttonbox(bb);
79 ret = handle;
80 return
81 case 'close'
82 if nargin > 0
83 handle = varargin{1};
84 else
85 handle = old_hdl;
86 end
87 fclose(handle);
88 ret = handle;
89 return
90 case 'run'
91 % read incoming data
92 if isempty(old_hdl)
93 help serial_buttonbox_common
94 error('Buttonbox not yet initialized');
95 end
96 handle = old_hdl;
97 % code proceeds below ....
98 case 'wait_keypress'
99 % read incoming data
100 if isempty(old_hdl)
101 help serial_buttonbox_common
102 error('Buttonbox not yet initialized');
103 end
104 handle = old_hdl;
105 while 1
106 % start polling for characters (indicating start of scan)
107 navailable = handle.BytesAvailable;
108 if navailable
109 data = [];
110 while navailable
111 % read incoming data
112 [newdata, cnt] = fread(handle, navailable);
113 % concatenate possible new data
114 if cnt
115 data = [data newdata(:)];
116 end
117 % check if any more data left
118 navailable = handle.BytesAvailable;
119 end
120 ret = data;
121 return
122 end
123 end %while 1
124 otherwise
125 fprintf('Unknown option %s\n',cmd);
126 ret = [];
127 return
128
129
130end
131
132%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
133% only gets here when cmd = 'run' %
134%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
135
136% Initialize output figure
137win = list_output(' ',[]);
138while 1
139 % Exit if user closed output figure
140 if ~ishandle(win)
141 return
142 end
143 % start polling for characters (indicating start of scan)
144 navailable = handle.BytesAvailable;
145 if navailable
146 data = [];
147 while navailable
148 % read incoming data
149 [newdata, cnt] = fread(handle, navailable);
150 % concatenate possible new data
151 if cnt
152 data = [data newdata(:)];
153 end
154 % check if any more data left
155 navailable = handle.BytesAvailable;
156 end
157 % output info about which button was pressed
158 for n = 1 : numel(data)
159 line = sprintf('incoming: %03d %s',data(n),char(data(n)));
160 list_output(line,win);
161 end
162 end
163 pause(0.01);
164end %while 1
165
166 function hdl = open_buttonbox(device)
167 % open handle to serial device (mini buttonbox)
168 try
169 hdl = serial(device.Device, 'Baudrate', device.BaudRate, 'DataBits', device.DataBits, 'StopBits', device.StopBits, 'Parity', device.Parity);
170 fopen(hdl);
171 catch
172 if ~isempty(old_hdl)
173 fclose(old_hdl);
174 delete(old_hdl);
175 end
176 hdl = serial(device.Device, 'Baudrate', device.BaudRate, 'DataBits', device.DataBits, 'StopBits', device.StopBits, 'Parity', device.Parity);
177 fopen(hdl);
178 end
179 old_hdl = hdl;
180
181 fprintf('Wait for device buttonbox....\n');
182 tic
183 while hdl.BytesAvailable && toc<10
184 navailable = bbox.BytesAvailable;
185 % wait for welcome message device
186 fread(hdl, navailable);
187 end
188 pause(0.5);
189
190 % while ~IOPort('BytesAvailable', hdl) && toc<10
191 % % wait for welcome message device
192 % end
193 % pause(0.5);
194
195 % clear buffer
196 %IOPort('flush', hdl);
197 IOPort('purge', hdl);
198
199 end
200
201 function win = list_output(line,win)
202 persistent ptr
203 persistent lines
204 persistent edt
205 Maxlines = 40;
206
207 if isempty(win)
208 % initialize listbox output figure
209 lines = cell(1,Maxlines);
210 [lines(1:end)]=deal({''});
211 ptr=Maxlines;
212 lines(ptr) = {'Buttonbox output:'};
213 idxs = mod(ptr:ptr+Maxlines-1,Maxlines)+1;
214
215 win = figure();
216 % initialize figure to hold output text
217 edt = uicontrol('Parent',win,'Style','ListBox','HorizontalAlignment','left', ...
218 'Max',Maxlines,'BackgroundColor',[1 1 1],'Visible','on','String',lines(idxs), ...
219 'FontSize',12,'Value',Maxlines);
220 pos = get(win,'Position');
221 set(edt,'Position',[1 1 pos(3) pos(4)]);
222 end
223 ptr = mod(ptr,Maxlines)+1; % start
224 lines{ptr} = line;
225 idxs = mod(ptr:ptr+Maxlines-1,Maxlines)+1;
226 set(edt,'String',lines(idxs),'Value',Maxlines);
227 drawnow;
228 end
229
230end