ButtonBoxes
General
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:
|
Signal / Button |
ASCII (rising / falling) |
Code (rising / falling) |
|
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 /activated?, a capital A will be sent to the serial port. A lowercase 'a' will be sent when the signal is deactivated?. 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?, 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.
|
Function |
Byte 1 (ASCII / code) |
Byte 2 |
|
Marker out |
M / 77 |
Marker value |
|
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 |
Trigger port settings
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 settings
Our hardware design allows to be connected to the computers USB and emulates a serial Port.
|
Baudrate |
115200 |
|
Parity |
none |
|
Data bits |
8 |
|
Stop bits |
1 |
|
Flow control |
none |
USB-Com port settings
TSG ButtonBox hardware 2013
TSG ButtonBox software 2013
Presentation Settings
| File:Buttonbox1.png |
Psychopy Settings
#!/usr/bin/env python
from psychopy import core, visual, event from rusocsci import buttonbox import logging, time
##Setup Section
#logging.getLogger().setLevel(logging.DEBUG) # use this for debug info
win = visual.Window([400,300], monitor="testMonitor") bb = buttonbox.Buttonbox()
##Experiment Section
b = bb.waitButtons(maxWait = 10.0, buttonList=['A']) print("b: {}".format(b))
##Cleanup Section
core.quit() The following script lights the LEDs under the buttons pressed.
#!/usr/bin/env python
#from __future__ import print_function
import logging, time, sys from rusocsci import buttonbox
##Setup Section
led = [False]*8
##Experiment Section
bb = buttonbox.Buttonbox() while True:
buttons = bb.getButtons()
if len(buttons):
for c in buttons:
if ord(c) >= ord('a') and ord(c) < ord('a')+8:
led[ord(c) - ord('a')] = False
elif ord(c) >= ord('A') and ord(c) < ord('A')+8:
led[ord(c) - ord('A')] = True
bb.setLeds(led)
#print("buttons ({:3d}): {}{}".format(len(buttons), buttons, " "*50), end="\r")
#sys.stdout.flush()
Matlab Settings
===================================================================================================
function handle = serial_buttonbox_common(cmd,varargin)
% to initialize connection:
% handle = serial_buttonbox('open',se)
% settings (se):
% define settings as a structure, i.e.:
% se.Device = 'COM1';
% se.BaudRate = 115200;
% se.DataBits = 8;
% se.StopBits = 1;
% se.Parity = 0;
% se.PTBPath = 'c:\MyToolboxes\PsychToolbox'
%
% to close the connection:
% serial_buttonbox('close',handle);
persistent old_hdl
% set defaults
se.Device = 'COM1';
se.BaudRate = 115200;
se.DataBits = 8;
se.StopBits = 1;
se.Parity = 0;
se.PTBPath = 'c:\Pgrogram Files\PsychToolbox';
if nargin < 1
cmd = 'open';
end
if nargin > 1
% user overwrites default settings
flds = fields(varargin{1});
for n = 1 : numel(flds)
se.(flds{n}) = varargin{1}.(flds{n});
end
end
switch cmd
case 'open'
addpath(genpath(se.PTBPath));
% get handle to serial device
handle = open_buttonbox(se.Device);
return
case 'close'
handle = varargin{1};
IOPort('close',handle);
return
case 'run'
% read incoming data
if isempty(old_hdl)
help serial_buttonbox_common
error('Buttonbox not yet initialized');
end
handle = old_hdl;
otherwise
fprintf('Unknown option %s\n',cmd);
return
end
% only gets here when cmd = 'run'
while 1
% start polling for characters (indicating start of scan)
navailable = IOPort('BytesAvailable', handle);
if navailable
data = [];
while navailable
% read incoming data
[newdata, ~, err] = IOPort('Read', handle, 0, navailable);
if ~isempty(err), disp(err); end
data = [data newdata];
%pause(0.001); % if possible just add a small pause to not claim entire core
navailable = IOPort('BytesAvailable', handle);
end
if numel(data)>1
fprintf('\nReceived characters: %d\n',numel(data));
end
for n = 1 : numel(data)
% disp(char(data(n)));
fprintf('incoming: %d\t%s\n',data(n),char(data(n)));
end
end
end %while 1
function hdl = open_buttonbox(device)
% open handle to serial device (mini buttonbox)
try
hdl = IOPort('OpenSerialPort',device,['BaudRate=' num2str(se.BaudRate)]);
catch
if ~isempty(old_hdl)
IOPort('close',old_hdl);
end
hdl = IOPort('OpenSerialPort',device,['BaudRate=' num2str(se.BaudRate)]);
end
old_hdl = hdl;
fprintf('Wait for device buttonbox....\n');
tic
while ~IOPort('BytesAvailable', hdl) && toc<10
% wait for welcome message device
end
pause(0.5);
% clear buffer
%IOPort('flush', hdl);
IOPort('purge', hdl);
end
end
Inquisit Settings
Work in progress
E-Prime
Work in progress