/usr/share/psychtoolbox-3/PsychHardware/CedrusResponseBox.m is in psychtoolbox-3-common 3.0.11.20131230.dfsg1-1build1.
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2022 2023 2024 2025 2026 2027 2028 2029 2030 2031 2032 2033 2034 2035 2036 2037 2038 2039 2040 2041 2042 2043 2044 2045 2046 2047 2048 2049 2050 2051 2052 2053 2054 2055 2056 2057 2058 2059 2060 2061 2062 2063 2064 2065 2066 2067 2068 2069 2070 2071 2072 2073 2074 2075 2076 2077 2078 2079 2080 2081 2082 2083 2084 2085 2086 2087 2088 2089 2090 2091 2092 2093 2094 2095 2096 2097 2098 2099 2100 2101 2102 2103 2104 2105 2106 2107 2108 2109 2110 2111 2112 2113 2114 2115 2116 2117 2118 2119 2120 2121 2122 2123 2124 2125 2126 2127 2128 2129 2130 2131 2132 2133 2134 2135 2136 2137 2138 2139 2140 2141 2142 2143 2144 2145 2146 2147 2148 2149 2150 2151 2152 2153 2154 2155 2156 2157 2158 2159 2160 2161 2162 2163 2164 2165 2166 2167 2168 2169 2170 2171 2172 2173 2174 2175 2176 2177 2178 2179 2180 2181 2182 | function varargout = CedrusResponseBox(cmd, varargin)
% CedrusResponseBox - Interface to Cedrus Response Boxes.
%
% This function provides an interface to response button boxes from Cedrus,
% specifically model RB 530,...,830 and compatible models supporting the
% XID protocol (see http://www.cedrus.com).
%
% These response boxes connect via a serial line link interface, or a USB
% interface which emulates a serial link interface. They support the XID
% protocol for communication. See http://www.cedrus.com/xid for details.
%
% This function allows to establish a connection to the box, control a few
% of its parameters and most importantly query its button state and
% associated button press timestamps.
%
% It supports multiple subcommands, which accept and return different
% arguments, as listed below.
%
% Limitations:
% ------------
%
% Functionality is currently limited mostly to button queries (and RJ-45
% connector state queries), including timestamps, as well as control of
% built-in timers of the box. We also support basic configuration of TTL
% ports, but not yet all settings of the box like e.g., button debounce
% time. Adding such calls is straightforward and simple.
%
% We found communication with the Cedrus boxes to be unreliable quite
% often. It is an open question if this is a flaw in the design of the
% Cedrus devices and their firmware or protocols, or if the programming
% documentation for them is incomplete and therefore our implementation of
% the driver. However, the problems were reproduced under different
% operating systems, serial port drivers, toolboxes by different
% implementations written by different people, so it doesn't seem to be a
% simple glitch in one implementation. In general, the boxes work, but
% don't be surprised if you need to restart your script multiple times
% before you can establish communication, or if the more advanced
% fucntions, e.g., for configuration of the TTL RJ-45 connector, work
% unreliably for no apparent reason. Cedrus has been contacted, but so far
% no resolution or response from them.
%
% In short: If you are looking for a reliable response box that is painfree
% to use, don't buy Cedrus devices!
%
%
% Subfunctions and their meaning:
% -------------------------------
%
% Functions for device init and shutdown: Call once at beginning/end of
% your script. These are slow!
%
% handle = CedrusResponseBox('Open', port [, lowbaudrate]);
% - Open a compatible response box which is connected to the given named
% serial 'port'. 'port'names differ accross operating systems. A typical
% port name for Windows would be 'COM2', whereas a typical port name on OS/X
% or Linux would be the name of a serial port device file, e.g.,
% '/dev/cu.usbserial-FTDI125ZX9' on OS/X, or '/dev/ttyS0' on Linux.
%
% All names on OS/X are like '/dev/cu.XXXXX', where the XXXXX part depends
% on your serial port device, typically '/dev/cu.usbserial-XXXXX' for
% serial over USB devices with product name XXXXX.
%
% On Linux, all names are of pattern '/dev/ttySxx' for standard serial
% ports, e.g., '/dev/ttyS0' for the first serial port in the system, and of
% type '/dev/ttyUSBxx' for serial over USB devices, e.g., '/dev/ttyUSB0'
% for the first serial line emulated over the USB protocol.
%
%
% After the connection is established and some testing and initialization is,
% done, the function returns a device 'handle', a unique identifier to use
% for all other subfunctions.
%
% By default the commlink is opened at a baud transmission rate of 115200
% Baud (All DIP switches on the box need to be in 'down' position!). If you
% specify the optional flag 'lowbaudrate' as 1, then the speed will be
% lowered to 56 kBaud at device open time -- in case your system works
% unreliably at the higher rate.
%
% By default, the script uses Psychtoolbox's own IOPort() serial link
% driver for communication (ptb_cedrus_drivertype = 2). If you want to use
% a different driver for testing, change the 'ptb_cedrus_drivertype'
% parameter inside the code with the id of a supported driver (Matlab
% serial() on Windows and Linux, SerialComm on OS/X). This option may go
% away in the future and is for debugging only!
%
%
% CedrusResponseBox('Close', handle);
% - Close connection to response box. The 'handle' becomes invalid after
% that command.
%
%
% CedrusResponseBox('CloseAll');
% - Close all connections to all response boxes. This is a convenience
% function for quick shutdown.
%
%
% dev = CedrusResponseBox('GetDeviceInfo', handle);
% - Return queried information about the device in a struct 'dev'. 'dev'
% contains (amongst other) the following fields:
%
% General information:
% dev.Name = Device name string.
% dev.VersionMajor and dev.VersionMinor = Major and Minor firmware revision.
% dev.productId = Type of device, e.g., 'Lumina', 'VoiceKey' or 'RB response pad'.
% dev.modelId = Submodel of the device if the device is a RB response pad,
% e.g., 'RB-530', 'RB-730', 'RB-830' or 'RB-834'.
%
% dev.port = Portname of serial port, as passed to the open function.
%
% Diagnostic information for timing: Values of -1 or 0 usually mean "info
% not available".
%
% dev.roundtriptime = Median of estimated roundtrip latency for
% communication with the box - in seconds.
%
% dev.roundtripstddev = Standard deviation from mean of roundtrip latency
% measurements in seconds. Large numbers mean that your operating system
% has bad scheduling and that reported event timestamps may be uncertain by
% that amount.
%
% dev.rttresetdelay = Duration (in seconds) of a reaction time timer reset sequence
% Values of more than 3 msecs indicate some problems with the box itself or
% the communication link -- Measured event times or reaction times may not
% be trustworthy!
%
%
% Functions for use within script. These are as fast as possible:
%
% CedrusResponseBox('ClearQueues', handle);
% - Clear all queues, discard all pending data.
%
% [status = ] CedrusResponseBox('FlushEvents', handle);
% - Empty/clear/flush the queue of pending events. Use this to get rid of
% any stale button press or release events before start of response
% collection in a trial. E.g., Assume you wait for a subjects keypress and
% finally receive that keypress via 'GetButtons' or 'WaitButtons'. You
% collected your response, the trial is done, but when the subject releases
% the button again, that will generate another event - a release event, in
% which you're not interested. Maybe the subject will accidentally hit the
% button as well. --> Good to clean the queue before a new trial.
%
% This function has a second use as well. It has an optional output
% argument, 'status', which will return the current status of all buttons
% (i.e. whether they are currently being pressed or not).
% Status is a 3 row by 8 column matrix: Row 1 describes the status of the
% up to eight pushbuttons of the box. Row 2 describes the status of the TTL
% lines of the RJ-45 accessory connector. Row 3 describes the status of the
% VoiceKey if any. Columns 1 to 8 of each row correspond to buttons 1-8,
% TTL lines 1-8 or inputs 1-8 of the VoiceKey.
%
% The mapping for the CB-530 for row 1 of 'status' status(1,:) is as follows:
%
% [top ??? left middle right bottom] -- the 2nd entry has no associated
% button, but it may be the scanner trigger input. The mapping on other boxes
% may be different.
%
% This is useful if you just want to know whether the subject is currently
% pressing any buttons before you proceed, but are not fussed about timing.
%
% E.g. I often find myself doing the following:
% buttons = 1;
% while any(buttons(1,:))
% buttons = CedrusResponseBox('FlushEvents', mybox);
% end
%
% ...to wait for the subject to release any buttons which might currently be down.
%
% evt = CedrusResponseBox('GetButtons', handle);
% - Return next queued button-press or button-release event from the box.
% Each time a button on the box is pressed or released, and each time the
% state of the accessory connector changes, an "event" data packet is sent
% from the box to the computer. The packet is timestamped with the time of
% the triggering event, as measured by the boxes reaction time timer.
%
% This function checks if such an event is available and returns its
% description in a 'evt' struct, if so. If no event is pending, it returns an
% empty 'evt', ie. isempty(evt) is true.
%
% 'evt' for a real fetched event is a struct with the following fields:
%
% evt.raw = "raw" byte that describes the event. Only for debugging.
%
% evt.port = Number of the device port on which the event occured. Push
% buttons and scanner triggers are on port 0, the RJ-45 TTL
% connector is on port 1, port 2 is the voice-key (if any).
%
% evt.action = Action that triggered the event:
% 1 = Button press, 0 = Button release for pushbuttons.
% 1 = TTL line high, 0 = TTL line low for RJ-45 I/O lines.
% 1 = Voice onse, 0 = Voice offset/silence for Voicekey.
%
% evt.button = Number of the button that was pressed or released (1 to 8)
% or the TTL line that was going high/low. Numbers vary by
% response box.
%
% evt.buttonID= Descriptive name string for pressed button, e.g., 'top' or
% 'left'. Please note that this mapping is only meaningful
% for the RB-530 response box.
%
% evt.rawtime = Time of the event in secs since last reset of the reaction
% time timer, measured in msecs resolution. This value is
% always valid, but not directly comparable to any other
% timestamps or time measurements within Psychtoolbox.
%
%
% evt = CedrusResponseBox('WaitButtons', handle);
% - Queries and returns the same info as 'GetButtons', but waits for
% events. If there isn't any event available, will wait until one becomes
% available.
%
% evt = CedrusResponseBox('WaitButtonPress', handle);
% - Like WaitButtons, but will wait until the subject /presses/ a key -- the
% signal that a key has been released is not acceptable -- Button release
% events are simply discarded.
%
%
% evt = CedrusResponseBox('GetBaseTimer', handle [, nSamples=1]);
% - Query current time of base timer of the box. Returned values are in
% seconds, resolution is milliseconds. evt.basetimer is the timers time,
% maybe corrected for serial link receive latency. evt.ptbreceivetime is a
% timestamp taken via PTB's GetSecs() at time of receive of the data.
% evt.ptbtime is the basetimers time mapped into PTB GetSecs time if such a
% mapping is possible, otherwise this field doesn't exist:
% evt.ptbreceivetime and evt.ptbtime shouldn't be significantly different
% if everything is good. Large differences indicate some timing problems
% with the connection to the box, or a timer problem - either with your
% computers timer or the hardware timer of the tox, or significant
% clock-drift between the computers timer and the boxes timer. In any case,
% reaction timer measurements and such will be problematic.
%
% Note that this automatically discards all pending events in the queue before
% performing the timer query!
%
% The optional argument 'nSamples' allows to specify if multiple samples of
% PTB timer vs. the response boxes timer should be measured. If 'nSamples'
% is set to a value greater than one, a cell array with nSamples elements
% will be returned, each corresponding to one measurement. This allows,
% e.g., to check if PTBs timer and the boxes timer drift against each
% other.
%
%
% resetTime = CedrusResponseBox('ResetRTTimer', handle);
% - Reset reaction time timer of box to zero. This should not be neccessary
% if you use the evt.ptbtime timestamps for time measurements or reaction
% time measurements. If you however use uncalibrated mode and the
% evt.rawtime values directly, this function may be useful to establish a
% zero baseline for reaction time measurements. However, as the communication
% delay for sending the reset command can't be reliably measured, using
% such a software triggered timer reset may not be the most reliable way of
% resetting the timer. The function returns 'resetTime' PTB's best guess of
% when the reset was carried out -- essentially a GetSecs() timestamp of
% when the reset command was sent.
%
% Note that this automatically discards all pending
% events in the queue before performing the query!
%
%
% slope = CedrusResponseBox('GetBoxTimerSlope', handle);
% - Compute slope (drift) between computer clock and device clock. 'slope'
% tells how many seconds of time "elapse" on the computer in GetSecs time
% for each "elapsed" second of box time. At device open time, the driver
% takes a timestamp from the device basetimer. This function also takes a
% timestamp and then computes the ratio of differences. The longer you'll
% wait after CedrusResponseBox('Open') before calling this function, the
% more accurate the clock-drift estimate will be.
%
%
% roundtrip = CedrusResponseBox('RoundTripTest', handle);
% - Initiate 100 trials of the roundtrip test of the box. Data is echoed
% forth and back 100 times between PTB and the box, and the latency is
% measured (in seconds, with msecs resolution). The vector of all samples
% is returned in 'roundtrip' for evaluation and debugging. The measured
% latency is also used for delay correction for the 'GetBaseTimer'
% subfunction. However, a roundtrip test is performed automatically when
% opening the response box connection, so this is rarely needed.
%
% Note that this automatically discards all pending
% events in the queue before performing the query!
%
%
% [currentMode] = CedrusResponseBox('SetConnectorMode', handle [, mode]);
% - Set or get mode of operation of external accessory connector: 'mode' can be
% any of the following text strings:
%
% 'GeneralPurpose': Input/Output assignment of pins can be freely
% programmed via the 'DefineInputLinesAndLevels' subcommand (see below),
% and the output lines only change if the 'SetOutputLineLevels' command
% (see below) is used. The connector doesn't change state by itself.
%
% 'ReflectiveContinuous': Line levels reflect button state: Line is active
% if button is pressed and goes inactive when the button is released again.
%
% 'ReflectiveSinglePulse': A single pulse is sent to an output line if a
% button is pressed on the box. Nothing is sent on release.
%
% 'ReflectiveDoublePulse': A single pulse is sent to an output line if a
% button is pressed on the box. Another pulse is sent on button release.
%
% If 'mode' is left out, the function queries and returns the current mode
% as return argument 'currentMode'. If mode is given, nothing is returned.
%
%
% CedrusResponseBox('SetOutputLineLevels', handle, outlevels);
% - Set accessory connector output lines to state specified in 'outlevels'.
% outlevels is an 8 element vector of zeros and ones. Each element
% corresponds to an output pin, and its values sets the output level of
% that pin. Example: outlevel = [1,1,1,1,0,0,0,0] would set the 4 lines
% with the lowest numbers (lines 0,1,2,3) to '1' aka active and the 4 lines
% with the highest numbers (lines 4,5,6,7) to '0' aka inactive.
% This corresponds to XiD command 'ah'.
%
% The command is only effective if connector is set to 'GeneralPurpose'.
%
%
% CedrusResponseBox('DefineInputLinesAndLevels', handle, inputlines, logiclevel, debouncetime);
% - Define which lines on the connector are inputs: 'inputlines' is a
% vector with the line numbers of the input lines. All other lines are
% designated as output lines, e.g., inputlines = [0, 2, 4] would set lines
% 0, 2 and 4 as inputs, remaining lines 1,3,5,6,7 as outputs. 'logiclevel'
% tells if the default TTL level of the input lines is low (logiclevel=1)
% or high (logiclevel=0). Example: logiclevel = 1 means that the lines are
% pulled low by default, so they will detect an active high state -- if
% their level is raised to TTL high state. The argument 'debouncetime' must
% be the debounce time for the input lines in milliseconds. After an event
% on a input line, the box will ignore all further events on than input
% line for 'debouncetime' milliseconds.
%
% This corresponds to XiD commands 'a4', 'a50' and 'a51', as well as 'a6'.
%
% The command is only effective if connector is set to 'GeneralPurpose'.
%
%
% inputLines = CedrusResponseBox('ReadInputLines', handle);
% - Read current state of the connectors input lines: Returns an 8 element
% vector where each element corresponds to one input line and a 1 means
% active, 0 means inactive. This corresponds to XiD command 'ar'.
%
% Note that this automatically discards all pending
% events in the queue before performing the query!
%
% The command is only effective if connector is set to 'GeneralPurpose'.
%
%
% Technical notes:
% USB VendorID of Cedrus: 0x0403
% USB ProductID: 0xf228
%
% Command for manual insertion of serial-over-USB module on Linux, if
% module doesn't recognize Cedrus device id's. Also edit rules files of
% usbdev, so ftdi_sio module gets auto-loaded on Cedrus insertion.
%
% sudo modprobe ftdi_sio product=0xf228
% Disabled help text snippets:
% [,doCalibrate=0]
% If you don't specify the optional 'doCalibrate' flag, or
% leave it at its default setting of 1, a couple of lengthy (multiple
% seconds) timing calibrations and tests are performed. These allow to
% assess the delays in communication between box and Matlab. They will also
% allow to return all times of events (as detected by the box) in PTB's
% standard GetSecs() time reference system -- Timestamps of button press
% events and TTL input events can be directly compared with timestamps
% delivered by other PTB functions like GetSecs, KbCheck, KbWait,
% Screen('Flip') etc.
%
% If you set the 'doCalibrate' flag to zero, all timing calibrations will
% be skipped: Startup time is drastically reduced. However there isn't any
% simple and straightforward way of comparing timestamps or timer readings
% delivered by the box with other timestamps of PTB functions. This only
% makes sense if you use some external triggering mechanism to reset the
% built-in reaction time timer via some external TTL input trigger signals
% and want to use raw timer measurements.
% evt.ptbtime = Time of the event in secs, measured in PTBs "GetSecs"
% timebase. This is easier to correlate with other
% timestamps, e.g., Screen('Flip') timestamps, but its
% reliability hasn't been tested yet for the current
% software release. When opening a connection to a response
% box, we perform timing calibrations to establish the
% mapping of time values as measured by the hardware timers
% of your response pad to time values in PTB's reference
% system. If you skipped that calibrations by setting the
% optional 'doCalibrate' flag to zero at device open time,
% then the evt.ptbtime field will not be available and you
% have to cope with evt.rawtime values only.
%
% History:
%
% 03/21/08 Written. Based on example code donated by Cambridge Research Systems. (MK)
% 03/28/08 Altered by Jenny Read.
% 04/03/08 Refined and added MacOS/X support via SerialComm driver. (MK)
% 04/06/08 Improved timing code for mapping of box timers --> GetSecs time. (MK)
% 04/17/08 Disable Boxtime->Ptbtime mapping for now, use old drivers. (MK)
% 04/23/08 Add additional setup and query commands for external port. (MK)
% 05/09/10 Add additional button label definitions for RB830, contributed
% by Jochen Laubrock. (MK)
% Hard-Coded drivertype to use: Defaults to our IOPort driver.
global ptb_cedrus_drivertype;
ptb_cedrus_drivertype = 2;
% Cell array of device structs. Globally available for main function and
% all subfunctions in this file, persistent across invocation:
global ptb_cedrus_devices;
% Subcommand dispatch:
if nargin < 1 || ~ischar(cmd)
error('Must at least specify subcommand as textstring!')
end
% Following if-end blocks are roughly sorted by frequency of use. The most
% frequently used calls come first to achieve minimum dispatch
% latency in the trial loop.
if strcmpi(cmd, 'FlushEvents')
% Flush all pending events/data:
if nargin < 2
error('You must provide the device "handle" for the box to flush!');
end
% Retrieve handle and check if valid:
handle = checkHandle(varargin{1});
% Perform flush:
CedrusStatus = FlushEvents(handle);
if nargout>0
varargout{1} = CedrusStatus;
end
return
end
if strcmpi(cmd, 'ClearQueues')
% Clear all pending events/data:
if nargin < 2
error('You must provide the device "handle" for the box to clear!');
end
% Retrieve handle and check if valid:
handle = checkHandle(varargin{1});
% Perform clear:
ClearQueues(handle);
return
end
% Wait until a key-pressed signal is detected:
if strcmpi(cmd, 'WaitButtonPress')
if nargin < 2
error('You must provide the device "handle" for the box to wait for!');
end
% Retrieve handle and check if valid:
handle = checkHandle(varargin{1});
% Wait until the box reports that a key has been pressed (NOT released)
keypress = 0;
while ~keypress
% Need at least 6 bytes. Only wait if not available:
if BytesAvailable(handle) < 6
% Poll at 4 msecs intervals as long as input buffer is totally empty,
% to allow the CPU to execute other tasks.
while BytesAvailable(handle) == 0
% Choose 4 msecs, as PTB would not release the cpu for wait
% times below 3 msecs (to account for MS-Windows miserable
% process scheduler).
if IsWin
WaitSecs(0.004);
else
WaitSecs(0.001);
end
end
% At least 1 byte available -- soon we'll have our required minimimum 6
% bytes :-) -- Spin-Wait for the remaining few microseconds:
while BytesAvailable(handle) < 6; end
end
% At least 6 bytes for one event available: Try to read them from box:
response = ReadDev(handle, 6);
% Timestamp receive completion in PTB's timeframe. Allows to get a
% feeling on how much time elapses between keypress and data receive:
ptbfetchtime = GetSecs;
% Unpack this binary data into a more readable form:
evt = ExtractKeyPressData(handle,response);
evt.ptbfetchtime = ptbfetchtime;
keypress = evt.action;
% This is 0 if the key was released, 1 if it was pressed down,
% which is what we are waiting for.
end
% Assign evt as output argument:
varargout{1} = evt;
return % JCAR added
end
% Wait for at least one button event available:
if strcmpi(cmd, 'WaitButtons')
if nargin < 2
error('You must provide the device "handle" for the box to wait for!');
end
% Retrieve handle and check if valid:
handle = checkHandle(varargin{1});
% Need at least 6 bytes. Only wait if not available:
if BytesAvailable(handle) < 6
% Poll at 4 msecs intervals as long as input buffer is totally empty,
% to allow the CPU to execute other tasks.
while BytesAvailable(handle) == 0
% Choose 4 msecs, as PTB would not release the cpu for wait
% times below 3 msecs (to account for MS-Windows miserable
% process scheduler).
if IsWin
WaitSecs(0.004);
else
WaitSecs(0.001);
end
end
% At least 1 byte available -- soon we'll have our required minimimum 6
% bytes :-) -- Spin-Wait for the remaining few microseconds:
while BytesAvailable(handle) < 6; end
end
% At least 6 bytes for one event available: Try to read them from box:
response = ReadDev(handle, 6);
% Timestamp receive completion in PTB's timeframe. Allows to get a
% feeling on how much time elapses between keypress and data receive:
ptbfetchtime = GetSecs;
% Unpack this binary data into a more readable form:
evt = ExtractKeyPressData(handle,response);
evt.ptbfetchtime = ptbfetchtime;
% Assign evt as output argument:
varargout{1} = evt;
return % JCAR added
end
% Polling Button state query: Returns immediately if no events available.
if strcmpi(cmd, 'GetButtons')
% Button state change event query:
if nargin < 2
error('You must provide the device "handle" for the box to query!');
end
% Retrieve handle and check if valid:
handle = checkHandle(varargin{1});
% XID devices send six bytes of information.
% Check if at least 6 bytes for a full event report are available:
if BytesAvailable(handle) < 6
% Did not receive at least 6 bytes - No new event happened. Return an
% empty evt result.
evt = [];
varargout{1} = evt;
return;
end
% At least 6 bytes for one event available: Try to read them from box:
response = ReadDev(handle, 6);
% Timestamp receive completion in PTB's timeframe. Allows to get a
% feeling on how much time elapses between keypress and data receive:
ptbfetchtime = GetSecs;
% Unpack this binary data into a more readable form:
evt = ExtractKeyPressData(handle,response);
evt.ptbfetchtime = ptbfetchtime;
% Assign evt as output argument:
varargout{1} = evt;
return;
end
if strcmpi(cmd, 'RoundTripTest')
% Initiate roundtrip-test procedure: Will receive data from device,
% echo it back, then receive a roundtrip timestamp:
if nargin < 2
error('You must provide the device "handle" for the box to query!');
end
% Retrieve handle and check if valid:
handle = checkHandle(varargin{1});
% Start roundtrip test and return results: They are also stored in the
% device struct of 'handle':
varargout{1} = RoundTripTestDev(handle);
return;
end
if strcmpi(cmd, 'ResetRTTimer')
% RT timer reset request:
if nargin < 2
error('You must provide the device "handle" for the box!');
end
% Retrieve handle and check if valid:
handle = checkHandle(varargin{1});
% Reset reaction time timer of device and assign estimated time of reset
% as basetime for all timing calculations:
varargout{1} = ResetRTT(handle);
return;
end
if strcmpi(cmd, 'Test')
% Flush all pending events/data:
if nargin < 2
error('You must provide the device "handle" for the box!');
end
% Retrieve handle and check if valid:
handle = checkHandle(varargin{1});
TestThis(handle);
return
end
if strcmpi(cmd, 'GetBaseTimer')
% Base Timer query:
if nargin < 2
error('You must provide the device "handle" for the box to query!');
end
% Retrieve handle and check if valid:
handle = checkHandle(varargin{1});
if nargin >=3
nQueries = varargin{2};
else
nQueries = 1;
end
% Preallocate output cell array:
evts = cell(nQueries, 1);
% Flush input buffer:
FlushEvents(handle);
for i=1:nQueries
% Send basetimer query code:
evt.roundtriptime = GetSecs;
WriteDev(handle, 'e3');
% Spin-Wait for first byte:
while BytesAvailable(handle) < 1; end;
% Timestamp receive completion of first byte. This is closest to the
% real time when the transmitted timer values was actually generated on
% the device:
evt.ptbreceivetime = GetSecs;
% Receive packet, then parse into raw timer value (in seconds):
evt.basetimer = receiveAndParseTimePacket(handle);
% Store roundtrip-time of query:
evt.roundtriptime = evt.ptbreceivetime - evt.roundtriptime;
% Correct reported time value of basetimer by half roundtrip delay
% of serial link: We assume that transmission took half the total
% measured roundtrip time, so we need to add that delay to the
% basetimer value to get an estimate of the "real" basetimer time
% at time of response packet receive "ptbtime":
evt.basetimer = evt.basetimer + ptb_cedrus_devices{handle}.roundtriptime/2;
% Assign mapped PTB GetSecs time if mapping possible:
if ptb_cedrus_devices{handle}.baseToPtbSlope ~= 0
% Simple linear equation mapping:
evt.ptbtime = ptb_cedrus_devices{handle}.baseToPtbOffset + ptb_cedrus_devices{handle}.baseToPtbSlope * evt.basetimer;
end
% Assign i'th measurement event:
evts{i} = evt;
end
% Assign evts as output argument:
if nQueries > 1
varargout{1} = evts;
else
varargout{1} = evt;
end
return;
end
if strcmpi(cmd, 'SetConnectorMode')
% Change mode of external accessory connector:
if nargin < 2
error('You must provide the device "handle" for the box!');
end
% Retrieve handle and check if valid:
handle = checkHandle(varargin{1});
if nargin < 3
% Query instead of set:
% Send query code:
WriteDev(handle, '_a1');
% Retrieve response:
cc = ReadDev(handle, 4);
WaitSecs(0.25);
switch char(cc)
case {'_a10'}
rc = 'generalpurpose';
case {'_a11'}
rc = 'reflectivecontinuous';
case {'_a12'}
rc = 'reflectivesinglepulse';
case {'_a13'}
rc = 'reflectivedoublepulse';
otherwise
rc = cc;
warning('SetConnectorMode received unknown old mode response!');
end
varargout{1} = rc;
return;
end
switch lower(char(varargin{2}))
case {'generalpurpose'}
cc = 'a10';
case {'reflectivecontinuous'}
cc = 'a11';
case {'reflectivesinglepulse'}
cc = 'a12';
case {'reflectivedoublepulse'}
cc = 'a13';
otherwise
error('Unknown connector mode specified to SetConnectorMode.');
end
% Send command code:
WriteDev(handle, cc);
WaitSecs(0.25);
return;
end
if strcmpi(cmd, 'DefineInputLinesAndLevels')
% Change I/O assignment and default logic level of pins:
if nargin < 2
error('DefineInputLinesAndLevels: You must provide the device "handle" for the box!');
end
if nargin < 3
error('DefineInputLinesAndLevels: You must provide the new list of integer input pin numbers!');
end
if nargin < 4
error('DefineInputLinesAndLevels: You must provide the new logic detection level for the inputs: 1 for "Detect Low->High transition", 0 for "Detect High->Low" !');
end
if nargin < 5
error('DefineInputLinesAndLevels: You must provide the new debounce time for TTL inputs in milliseconds !');
end
% Retrieve handle and check if valid:
handle = checkHandle(varargin{1});
ClearQueues(handle);
inpins = varargin{2};
if ~isnumeric(inpins)
error('DefineInputLinesAndLevels: You must provide the new list of integer input pin numbers!');
end
if ~isempty(inpins)
if min(inpins) < 0 || max(inpins) > 5
error('DefineInputLinesAndLevels: Only input pin numbers between 0 and 5 are valid!');
end
end
ipin = 0;
for i=1:length(inpins)
ipin = ipin + 2^(inpins(i));
end
% Send command code and mask:
WriteDev(handle, ['a4' char(ipin)]);
% Wait a bit:
WaitSecs(1);
ClearQueues(handle);
WaitSecs(1);
% Retrieve new mask:
WriteDev(handle, '_a4');
WaitSecs(1);
resp = ReadDev(handle, 4);
if length(resp)<4 || ~strcmp(char(resp(1:3)), '_a4')
warning('DefineInputLinesAndLevels: Invalid response received from device!');
char(resp) %#ok<NOPRT>
varargout{1} = 0;
return;
else
if resp(4)~=ipin
warning('DefineInputLinesAndLevels: Real I/O bitmask not equal to requested one!');
resp(4) %#ok<NOPRT>
varargout{1} = 0;
return;
end
end
WaitSecs(1);
% Send new TTL pull-level:
if varargin{3} > 0
% Pull lines low --> Detect lines high:
cc = 'a50';
else
% Pull lines high --> Detect lines low:
cc = 'a51';
end
WriteDev(handle, cc);
WaitSecs(1);
ClearQueues(handle);
WriteDev(handle, '_a5');
WaitSecs(1);
% Query pull level:
resp = ReadDev(handle, 4);
if length(resp) < 4
warning('DefineInputLinesAndLevels: No response received from device!');
varargout{1} = 0;
return;
end
if ~strcmp(char(resp(1:3)), '_a5')
warning('DefineInputLinesAndLevels: Invalid response received from device!');
char(resp) %#ok<NOPRT>
varargout{1} = 0;
return;
else
if ~strcmp(char(resp(2:4)), cc)
warning('DefineInputLinesAndLevels: Real TTL default not equal to requested one!');
resp(2:4) %#ok<NOPRT>
varargout{1} = 0;
return;
end
end
WaitSecs(1);
% Send new debounce time:
WriteDev(handle, ['a6' char(double(varargin{4}))]);
WaitSecs(1);
ClearQueues(handle);
% Read it back:
WriteDev(handle, '_a6');
WaitSecs(1);
% Query debounce time:
resp = ReadDev(handle, 4);
if length(resp) < 4
warning('DefineInputLinesAndLevels: No response received from device!');
varargout{1} = 0;
return;
end
if ~strcmp(char(resp(1:3)), '_a6')
warning('DefineInputLinesAndLevels: Invalid response received from device!');
char(resp);
varargout{1} = 0;
return;
else
if resp(4) ~= double(varargin{4})
warning('DefineInputLinesAndLevels: Real TTL debounce time not equal to requested one!');
double(resp(4));
varargout{1} = 0;
return;
end
end
WaitSecs(1);
varargout{1} = 1;
return;
end
if strcmpi(cmd, 'ReadInputLines')
% Retrieve state of all input lines:
if nargin < 2
error('You must provide the device "handle" for the box!');
end
% Retrieve handle and check if valid:
handle = checkHandle(varargin{1});
% Flush event queue:
FlushEvents(handle);
% Send command code:
WriteDev(handle, 'ar');
% Read one byte back:
inplines = ReadDev(handle, 1);
outv=zeros(1,8);
for i=0:7
if bitand(inplines, 2^i)
outv(i+1)=1;
end
end
varargout{1} = outv;
return;
end
if strcmpi(cmd, 'SetOutputLineLevels')
% Change signal level of output pins:
if nargin < 2
error('You must provide the device "handle" for the box!');
end
if nargin < 3
error('You must provide the 8 element vector of output line levels!');
end
% Retrieve handle and check if valid:
handle = checkHandle(varargin{1});
opins = varargin{2};
if length(opins)~=8 || ~isnumeric(opins)
error('You must provide an 8 element vector of output line levels!');
end
outval = 0;
for i=1:8
if opins(i)>0
outval = outval + 2^(i-1);
end
end
% Send command code and mask:
WriteDev(handle, ['ah' char(outval)]);
% Wait a bit:
WaitSecs(0.1);
return;
end
if strcmpi(cmd, 'GetDeviceInfo')
% Query info about device:
if nargin < 2
error('You must provide the device "handle" for the box to query!');
end
% Retrieve handle and check if valid:
handle = checkHandle(varargin{1});
dev = ptb_cedrus_devices{handle};
varargout{1} = dev;
return; % JCAR added
end
if strcmpi(cmd, 'Open')
% Open a new connection to response box:
if nargin < 2
error('You must provide the "port" parameter for the serial port to which the box is connected!')
end
% Create serial object for provided port, configure connection
% properly:
port = varargin{1};
% port = '/dev/cu.usbserial-FT3Z95V5'
if nargin < 3
% Assume user doesn't want time calibration:
lowbaudrate = 0;
else
lowbaudrate = varargin{2};
end
if nargin < 4
% Assume user doesn't want time calibration:
doCalibrate = 0;
else
doCalibrate = varargin{3};
end
% Open device link at default baudrate of 115 kBaud, return 'dev' struct:
dev = OpenDev(port, 115200);
% Create new entry in our struct array:
if isempty(ptb_cedrus_devices)
ptb_cedrus_devices = cell(1,1);
else
ptb_cedrus_devices(end+1) = cell(1,1);
end
% Get a handle to it:
handle = length(ptb_cedrus_devices);
% Assign device struct to array:
ptb_cedrus_devices{handle} = dev;
clear dev;
if lowbaudrate
% Set the device protocol to XID mode
WriteDev(handle, 'c10'); %JCAR removed cr
% Give device time to settle:
WaitSecs(0.5);
% Initiate a device reset:
WriteDev(handle, 'f7');
% Give device time to settle:
WaitSecs(0.5);
% Change baudrate of device to 57600 Baud:
WriteDev(handle, ['f1' char(3)])
% Give device time to settle:
WaitSecs(0.5);
% Close connection:
CloseDev(handle);
% Give device time to settle:
WaitSecs(0.5);
% Reinit connection at new baud rate:
% Open device link at new baudrate of 57600 Baud, return 'dev' struct:
dev = OpenDev(port, 57600);
% Reassign device struct to array:
ptb_cedrus_devices{handle} = dev;
clear dev;
else
% Set the device protocol to XID mode
WriteDev(handle, 'c10'); %JCAR removed cr
% Give device time to settle:
WaitSecs(0.5);
% Initiate a device reset:
WriteDev(handle, 'f7');
% Give device time to settle:
WaitSecs(0.5);
end
% This is for keeping track of what buttons are currently up or
% down. I assume that all buttons are up when the device is opened.
ptb_cedrus_devices{handle}.CedrusStatus = zeros(3,8);
% Put this in a try-catch loop so that if it doesn't work for any
% reason, I can then close the link and you can try again. Otherwise,
% the COM port is permanently busy and I have to restart Matlab.
% try
% % Debug information from http://www.cedrus.com/xid/properties.htm
% %
% % Note: 0 is ASCII value 48, 1 is ASCII value 49, and so forth.
%
% fprintf(s1,['_d3',char(13)]);
% fread(s1,1)
% fprintf(s1,['_d1',char(13)]);
% fscanf(s1)
% Query a few device properties:
% Get product ID: 0 = Lumina, 1 = VoiceKey, 2 = RB response pad:
% I have to put this in a while loop, because sometimes '_d2' fails to
% evoke a response:
bytes = 0;
while bytes==0
WriteDev(handle, '_d2');
WaitSecs(0.25); % I also have to wait, because even when it does evoke a response,
% there can be a long delay - tens of milliseconds. Jon Peirce confirms
% this.
bytes = BytesAvailable(handle);
end
response=ReadDev(handle, bytes);
response=response(1);
switch response(1)
case 48
ptb_cedrus_devices{handle}.productID = 'Lumina';
case 49
ptb_cedrus_devices{handle}.productID = 'VoiceKey';
case 50
ptb_cedrus_devices{handle}.productID = 'RB response pad';
otherwise
ptb_cedrus_devices{handle}.productID = 'Unknown';
end
% Get model ID: 0 = Unknown, 1 = RB-530, 2 = RB-730, 3 = RB-830, 4 = RB-834
% I have to put this in a while loop, because sometimes '_d3' fails to
% evoke a response:
% Give device time to settle:
WaitSecs(0.5);
% Remove junk - if any:
while BytesAvailable(handle)
ReadDev(handle, 1);
end
bytes = 0;
while bytes==0
WriteDev(handle, '_d3');
WaitSecs(0.25); % I also have to wait, because even when it does evoke a response,
% there can be a long delay - tens of milliseconds. Jon Peirce confirms
% same behaviour on his system.
bytes = BytesAvailable(handle);
end
response=ReadDev(handle, bytes);
response=response(1);
if response==48
ptb_cedrus_devices{handle}.modelID = 'Unknown';
ptb_cedrus_devices{handle}.modelNo = 0;
else if strcmp(ptb_cedrus_devices{handle}.productID,'RB response pad')
switch response
case 49
ptb_cedrus_devices{handle}.modelID = 'RB-530';
ptb_cedrus_devices{handle}.modelNo = 530;
case 50
ptb_cedrus_devices{handle}.modelID = 'RB-730';
ptb_cedrus_devices{handle}.modelNo = 730;
case 51
ptb_cedrus_devices{handle}.modelID = 'RB-830';
ptb_cedrus_devices{handle}.modelNo = 830;
case 52
ptb_cedrus_devices{handle}.modelID = 'RB-834';
ptb_cedrus_devices{handle}.modelNo = 834;
otherwise
ptb_cedrus_devices{handle}.modelID = sprintf('Unknown id %i', response);
ptb_cedrus_devices{handle}.modelNo = 0;
end
else
ptb_cedrus_devices{handle}.modelID = 'Unknown';
ptb_cedrus_devices{handle}.modelNo = 0;
end
end
% Firmware revision:
bytes = 0;
while bytes==0
WriteDev(handle, '_d4');
WaitSecs(0.1);
bytes = BytesAvailable(handle);
end
ptb_cedrus_devices{handle}.VersionMajor = ReadDev(handle, bytes) - 48;
bytes = 0;
while bytes==0
WriteDev(handle, '_d5');
WaitSecs(0.1);
bytes = BytesAvailable(handle);
end
ptb_cedrus_devices{handle}.VersionMinor = ReadDev(handle, bytes) - 48;
% Product name string:
bytes = 0;
while bytes==0
WriteDev(handle, '_d1');
WaitSecs(0.1);
bytes = BytesAvailable(handle);
end
% Weird casting procedure with replacement of char(13) by char(10),
% so Octave can handle it:
ptb_cedrus_devices{handle}.Name = double(ReadDev(handle, bytes));
ptb_cedrus_devices{handle}.Name(find(ptb_cedrus_devices{handle}.Name == 13)) = 10; %#ok<FNDSB>
ptb_cedrus_devices{handle}.Name = char(ptb_cedrus_devices{handle}.Name);
% Try our best to totally drain the receive queue:
WaitSecs(0.25);
while 1
bytes = BytesAvailable(handle);
if bytes == 0
break;
end
ReadDev(handle, bytes)
WaitSecs(0.1);
end
% Reset base timer:
WriteDev(handle, 'e1');
% Calibration of PTB's timebase vs. Boxes timebase wanted?
if doCalibrate
% Set slope of 1 as a flag that ResetRTT should do a
% calibrated, timestamped reset:
ptb_cedrus_devices{handle}.baseToPtbSlope = 1;
% Perform calibrated basetimer query:
[hosttime, devicetime, minwin] = queryBaseTimer(handle);
% And store its results:
ptb_cedrus_devices{handle}.lastBaseTimeQuery = [hosttime, devicetime, minwin];
else
% Uncalibrated mode requested. Saves a few seconds of startup
% time, but doesn't allow mapping of boxes time measurements
% into GetSecs() timebase of PTB:
% No link roundtrip time estimates available:
ptb_cedrus_devices{handle}.roundtriptime = 0;
ptb_cedrus_devices{handle}.roundtripstddev = 0;
% No mapping of box time to PTB time available:
ptb_cedrus_devices{handle}.baseToPtbSlope = 0;
ptb_cedrus_devices{handle}.baseToPtbOffset = 0;
ptb_cedrus_devices{handle}.lastBaseTimeQuery = [];
end
% Reset reaction time timer of device: If calibration was
% requested, this will also estimate the offset between RTT values
% and basetimer values, which is needed for later mapping of RTT to
% GetSecs time. In uncalibrated mode, this will just send out the
% reset code.
ResetRTT(handle);
% Return handle:
varargout{1} = handle;
% catch
% Close serial control link:
% CloseDev(handle);
% end
return;
end
if strcmpi(cmd, 'GetBoxTimerSlope')
% Close device:
if nargin < 2
error('You must provide the device "handle" for the box to compute slope for!');
end
% Retrieve handle and check if valid:
handle = checkHandle(varargin{1});
% Perform calibrated basetimer query:
[hosttime, devicetime] = queryBaseTimer(handle);
lastBaseTimeQuery = ptb_cedrus_devices{handle}.lastBaseTimeQuery;
baseToPtbSlope = (hosttime - lastBaseTimeQuery(1)) / (devicetime - lastBaseTimeQuery(2));
% Store measured slope internally:
ptb_cedrus_devices{handle}.baseToPtbSlope = baseToPtbSlope;
% Return measured slope:
varargout{1} = baseToPtbSlope;
return;
end
if strcmpi(cmd, 'Close')
% Close device:
if nargin < 2
error('You must provide the device "handle" for the box to close!');
end
% Retrieve handle and check if valid:
handle = checkHandle(varargin{1});
CloseDev(handle);
return;
end
if strcmpi(cmd, 'CloseAll')
% Close all open devices:
if exist('ptb_cedrus_devices', 'var')
for handle = 1:length(ptb_cedrus_devices)
if ~isempty(ptb_cedrus_devices{handle})
CloseDev(handle);
end
end
% All handles closed: Release the device array itself:
clear ptb_cedrus_devices;
end
return;
end
error('Invalid subcommand given. Read the help.');
% ---- End of main routine ----
% ---- Start of internal helper functions ----
function TestThis(handle)
% Generic test blurb...
global ptb_cedrus_devices; %#ok<NUSED>
persistent testbyte;
if isempty(testbyte)
testbyte = 0;
end
% Flush input buffer:
WaitSecs(0.2);
FlushEvents(handle);
WaitSecs(0.2);
% Set general mode for lines: "General purpose"
WriteDev(handle, 'a10');
WaitSecs(0.4);
% Set direction for lines: All output.
WriteDev(handle, ['a4' 0]);
WaitSecs(0.4);
% Query current state of outputs and inputs:
WriteDev(handle, 'ar');
% Wait for response:
inputLines = dec2bin(ReadDev(handle, 1)); %#ok<NASGU>
basetime = WaitSecs(0.5); %#ok<NASGU>
% Set all output lines low:
testbyte = mod(testbyte + 1, 256);
WriteDev(handle, ['ah' testbyte]);
%WriteDev(handle, ['ah' 255]);
WaitSecs(0.4);
WriteDev(handle, '_ah');
% Any activity, e.g., events???
%while BytesAvailable(handle) == 0
% fprintf('Nothing yet at %f secs...\n', GetSecs - basetime);
%end
WaitSecs(0.1);
response = ReadDev(handle, 4); %#ok<NASGU>
%response2 = ReadDev(handle, 6)
% if length(response) == 6
% [evt,CedrusStatus] = ExtractKeyPressData(handle,response)
% end
return;
function tReset = ResetRTT(handle)
% Try to reset the reaction time timer to zero within a small time
% window, so we can associate "time zero" of the RT timer with the
% current GetSecs() time. This way, the RT timer will encode elapsed
% time since that GetSecs basetime. We can then later on compute the
% time of a keypress simply as sum of the GetSecs baseline time and the
% reported event time (== value of RT timer at time of button press).
% Retry up to 100 times if reset doesn't occur within 10ms.
global ptb_cedrus_devices;
% Calibrated reset?
if ptb_cedrus_devices{handle}.baseToPtbSlope ~= 0
% Calibrated reset:
% Flush input buffer:
WaitSecs(1);
ClearQueues(handle);
WaitSecs(1);
% Switch to realtime priority if not already there:
oldPriority=Priority;
if oldPriority < MaxPriority('GetSecs')
Priority(MaxPriority('GetSecs'));
end
% Get porthandle:
blocking = 1;
ntrials = 5;
s = ptb_cedrus_devices{handle}.link;
t = zeros(2,ntrials);
% Perform up to ntrials trials:
for ic=1:ntrials
% Wait some random fraction of a millisecond. This will desync us
% from the USB duty cycle and increase the chance of getting a very
% small time window between scheduling, execution and acknowledge
% of the send operation:
WaitSecs(rand / 1000 + 1);
% Take pre-Write timestamp: Sync command not emitted before that time:
% Write sync command, wait 'blocking' for write completion, store
% completion time in t(2,ic). Send RTT reset command code 'e5':
[nw t(2,ic), errmsg, t(1,ic)] = IOPort('Write', s, 'e5', blocking);
% We know that sync command emission has happened at some time
% after t(1,ic) and before t(2,ic). This by design of the USB
% standard, host controllers and operating system USB stack. This
% is the only thing we can take for granted wrt. timing, so the
% "time window" between those two timestamps is our window of
% uncertainty about the real host time when sync started. However,
% on a well working system without massive system overload one can
% be reasonably confident that the real emission of the sync
% command happened no more than 1 msec before t(2,ic). That is a
% soft constraint however - useful for computing the final estimate
% for hosttime, but nothing to be taken 100% for granted.
if nw~=2
% Send op failed!
fprintf('CedrusResponseBox: RTTReset: Warning! Sync token send operation to box failed!\n');
t(1,ic) = 0;
t(2,ic) = inf;
continue;
end
confidencewindow = t(2,ic) - t(1,ic);
if confidencewindow < 0.001
break;
end
% Next trial...
end
% Restore priority
if Priority ~= oldPriority
Priority(oldPriority);
end
% For each measurement, the time window t(2,ic)-t(1,ic) defines kind of
% a confidence interval for the "real" host system time when the sync
% command was emitted. The measurement with the smallest time window is
% the most accurate one. Find it and use it:
minwin = t(2,ic) - t(1,ic);
% On OS/X or Linux we could easily do with 2 msecs, as a 1.2 msecs
% minwin is basically never exceeded. On MS-Windows however, 2.x
% durations are not uncommon, so we need to slack this to 3.
if minwin > 0.002
fprintf('CedrusResponseBox: RTTReset: Warning! Confidence interval for clock sync is %f msecs - More than 2 msecs!\n', minwin);
end
% If the 'minwin' window is smaller than 1 msec, we subtract 0.5 the
% length of it from the t(2,idx) timestamp as best estimate for
% hosttime -- reasonable assuming a uniform distribution in the
% 'minwin' interval. If 'minwin' is more than 1 msecs, we assume it
% happened 0.5 msecs before t(2,idx) -- taking advantage of the
% soft-constraint that the real write usually happens within 1 msec of
% t(2,idx) on a normally loaded and well working system:
hosttime = t(2,ic) - (min(minwin, 0.001)/2);
WaitSecs(0.2);
FlushEvents(handle);
WaitSecs(0.2);
ptb_cedrus_devices{handle}.baseToPtbOffset = hosttime;
ptb_cedrus_devices{handle}.rttresetdelay = minwin;
tReset = minwin;
else
% Only uncalibrated fast reset requested:
% Reset offset fields to invalid values:
ptb_cedrus_devices{handle}.baseToPtbOffset = 0;
ptb_cedrus_devices{handle}.rttresetdelay = -1;
% Send reaction time timer reset code:
dx1 = GetSecs;
WriteDev(handle, 'e5');
dx2 = GetSecs;
% Return estimated time of when reset probably roughly happened:
tReset = (dx1+dx2)/2;
end
return;
function ClearQueues(handle)
while BytesAvailable(handle)>0
% Read and discard all bytes:
ReadDev(handle, BytesAvailable(handle));
WaitSecs(0.5);
end
return;
function CedrusStatus=FlushEvents(handle)
% JCAR: I modified this because I don't want to just throw away information
% about key-presses. If I do, I lose track of what the current button
% status is. So, I will read the information and check whether any of it
% is key-presses. If so, I will use this information to update the current
% status.
global ptb_cedrus_devices;
CedrusStatus = ptb_cedrus_devices{handle}.CedrusStatus;
while BytesAvailable(handle)>0
% Read 1 byte
response=ReadDev(handle, 1);
% See if this is "k", indicating that a key press is following
if char(response)=='k'
% Seems to be an event packet: Read remaining 5 more bytes
last5=ReadDev(handle, 5);
response(1:6) = [response(1) last5];
[evt,CedrusStatus] = ExtractKeyPressData(handle,response);
else
fprintf('CedrusResponseBox:FlushEvents: Warning invalid value %s [%i] instead of "k" received!\n', char(response), response);
end
end
return;
function label = findbuttonlabel(numbr, handle)
% The response box labels buttons by rather arbitrary numbers.
% I thought it might be helpful to have something more descriptive.
% THese descriptions assume the box is postioned with its cables/ports
% on the back edge furthest from the user.
global ptb_cedrus_devices;
switch (ptb_cedrus_devices{handle}.modelNo)
case 530
switch (numbr - 1)
case 1
label = 'top';
case 6
label = 'bottom';
case 3
label = 'left';
case 5
label = 'right';
case 4
label = 'middle';
otherwise
label = 'unknown';
end
case 730
switch (numbr)
case 2
label = '1.Left';
case 3
label = '2.Left';
case 4
label = '3.Left';
case 5
label = '4.Left';
case 6
label = '5.Left';
case 7
label = '6.Left';
case 8
label = '7.Left';
otherwise
label = 'unknown';
end
% arrangement of key codes for Cedrus 830
% left right hand
% 4 5 6 7
% 8 1
% 2 3
case 830
switch (numbr)
case 1
label = 'right.outer';
case 2
label = 'left.lower';
case 3
label = 'right.lower';
case 4
label = 'left.center';
case 5
label = 'left.inner';
case 6
label = 'right.inner';
case 7
label = 'right.center';
case 8
label = 'left.outer';
otherwise
label = 'unknown';
end
otherwise
label = 'unknown';
end
return;
function [evt,CedrusStatus] = ExtractKeyPressData(handle,response)
%The XID device sends six bytes of information in the following format:
%<�k�><key info><RT>:
%
% The first parameter is simply the letter "k", lower case.
%
% The second parameter consists of one byte, divided into the following
% bits
%
% Bits 0-3 store the port number. For Lumina LP-400, the push buttons and
% scanner trigger are on port 0; the RJ45 I/O lines are on port 1.
% For SV?1, voice key is on port 2 and the RJ45 is on port 1 ? there is
% no port 0. For the RB-x30 response pads, the push buttons are on port 0
% and the RJ45 port is on port 1.
%
% Bit 4 stores an action flag. If set, the button has been pressed. If
% cleared, the button has been released.
%
% Bits 5-7 indicate which push button was pressed.
%
% The reaction time consists of four bytes and is the time elapsed since
% the Reaction Time timer was last reset. See description of command "e5".
%
% Information taken from http://www.cedrus.com/xid/protocols.htm
global ptb_cedrus_devices;
if length(response)~=6
% Did not receive 6 bytes - This should not happen!
error('In GetButtons: Received too short (or no) response packet from box!');
end
% According to cedrus, http://www.cedrus.com/xid/protocols.htm,
% The XID device sends six bytes of information in the following
% format: <�k�><key info><RT>:
% So the first byte is 107, ie the letter �k�, lower case
% Check byte 1 for correct value 'k':
if char(response(1))~='k'
% Failed!
error('Received invalid event packet [Not starting with a k] from box!');
end
% Extracts byte 2 to determine which button was pushed:
evt.raw = (response(2));
% Extract different bits into meaningful fields:
% According to Cedrus, the second parameter consists of one byte, divided into the following bits:
% Bits 0-3 store the port number.
% For Lumina LP-400, the push buttons and scanner trigger are on port 0;
% the RJ45 I/O lines are on port 1. For SV?1, voice key is on port 2 and
% the RJ45 is on port 1 � there is no port 0.
% For the RB-x30 response pads, the push buttons are on port 0 and the
% RJ45 port is on port 1.
% Port id: Bits 0-3
evt.port = bitand(evt.raw, 15);
% 15 is 1111, so this extracts the rightmost 4 bits from evt.raw, ie bits 0-3
% Button state: 1 = pressed, 0 = released. Bit 4
evt.action = bitand(bitshift(evt.raw, -4), 1);
% Button id: Which button? Bits 5-7
evt.button = bitshift(evt.raw, -5) + 1;
% This chops off the rightmost 5 bits, i.e. bits 0-4, leaving only bits
% 5-7
% Map to a more descriptive label:
evt.buttonID = findbuttonlabel(evt.button, handle);
% Extracts bytes 3-6 and is the time elapsed in milliseconds since the
% Reaction Time timer was last reset.
%
% For more information about the use of XID timers refer to
% http://www.cedrus.com/xid/timing.htm
response = double(response);
evt.rawtime = 0.001 * (response(3)+(response(4)*256)+(response(5)*65536) +(response(6)*(65536*256)));
% Map rawtime to ptbtime if possible:
ptbTime = mapRTTimerToPTBTime(evt.rawtime, handle);
% Valid mapping? Assign if so. If mapping is impossible due to skipped
% timecalibration, we don't return the 'ptbtime' field. This way, usercode
% that relies on it without performing the mandatory calibration will die
% with a nice error message.
if ~isnan(ptbTime)
evt.ptbtime = ptbTime;
end
% Try and keep track of which buttons are currently down and up, based on
% what bytes have been read in.
ptb_cedrus_devices{handle}.CedrusStatus(evt.port + 1, evt.button) = evt.action;
% CedrusStatus will tell you what buttons are currently up or down,
% based on the last time the device was read.
CedrusStatus = ptb_cedrus_devices{handle}.CedrusStatus;
return;
% Check if 'handle' is a valid handle into our struct array of devices,
% return it if it is valid, abort with error otherwise.
function retHandle = checkHandle(handle)
global ptb_cedrus_devices;
if handle > length(ptb_cedrus_devices) || isempty(ptb_cedrus_devices{handle})
error('Invalid response box handle %i passed: No such response box device open!', handle);
end
retHandle = handle;
return;
% Helper function: Open serial connection:
function dev = OpenDev(port, baudrate)
global ptb_cedrus_drivertype;
% Test our default of type 2 -- Our own IOPort() driver:
if ptb_cedrus_drivertype == 2
% Use IOPort:
% Temporarily shut up the driver, so errors can be reasonably
% handled:
oldverb = IOPort('Verbosity', 0);
% Open link:
[dev.link, errmsg] = IOPort('OpenSerialPort', port, sprintf('BaudRate=%i Parity=None DataBits=8 StopBits=1 FlowControl=Hardware ReceiveTimeout=1 ', baudrate));
IOPort('Verbosity', oldverb);
% Success?
if dev.link < 0
% Nope. Do we know the cause?
error(sprintf('Failed to open port %s for Cedrus response box via IOPort()! Reason: %s', port, errmsg)); %#ok<SPERR>
end
% Link is online.
try
% Clear all send and receive buffers and queues:
IOPort('Purge', dev.link);
% Assign output port, driverid and empty recvQueue:
dev.driver = 2;
dev.recvQueue = [];
dev.port = port;
catch
error('Failed to open port %s for Cedrus response box via IOPort() driver.', port);
end
% Ready.
return;
end
% Some non-standard driver: We support serial() on Windows and Linux,
% SerialComm on OS/X:
% Which OS?
if IsOSX
% SerialComm:
try
% Open 'port' with 'baudrate' baud, no parity, 8 data bits, 1
% stopbit.
SerialComm('open', port, sprintf('%i,n,8,1', baudrate));
% Disable handshaking 'n' == none:
SerialComm('hshake', port, 'n');
% Wait a bit...
WaitSecs(0.5);
% And flush all send- and receivebuffers:
purgedata = SerialComm('read', port);
if ~isempty(purgedata)
fprintf('CedrusResponseBox: Open: Purged some trash data...\n');
end
% Assign and init stuff:
dev.port = port;
dev.link = port;
dev.driver = 1;
dev.recvQueue = [];
catch
error('Failed to open port %i on OS/X for Cedrus response box via SerialComm() driver.', port);
end
else
% Windows or Linux: Matlab supports serial() object in JVM mode:
if ~psychusejava('desktop')
error('You must run Matlab in JVM mode (JAVA enabled) for Cedrus response box to work!');
end
try
% Ok, Matlab with JVM on Windows or Linux: Let's do it!
dev.link = serial(port, 'BaudRate', baudrate, 'DataBits', 8, 'StopBits', 1,...
'FlowControl', 'none', 'Parity', 'none', 'Terminator', 'CR', 'Timeout', 400,...
'InputBufferSize', 16000);
fopen(dev.link);
dev.driver = 0;
dev.port = port;
dev.recvQueue = [];
catch
error('Failed to open port %s on Windows or Linux for Cedrus response box via Matlab serial() driver.', port);
end
end
% Ready.
return;
function CloseDev(handle)
global ptb_cedrus_devices;
% Give device time to settle:
WaitSecs(0.5);
% Initiate a device reset:
% WriteDev(handle, 'f7');
% Give device time to settle after reset:
WaitSecs(0.5);
if ptb_cedrus_devices{handle}.driver == 0
% Matlabs serial() driver:
% Close serial control link:
dev = ptb_cedrus_devices{handle};
% Close data link:
fclose(dev.link);
% Delete serial control link object:
delete(dev.link);
clear dev.link;
else
if ptb_cedrus_devices{handle}.driver == 1
% OS/X + Matlab + SerialComm driver:
SerialComm('purge', ptb_cedrus_devices{handle}.link);
SerialComm('close', ptb_cedrus_devices{handle}.link);
end
if ptb_cedrus_devices{handle}.driver == 2
% IOPort driver:
IOPort('Purge', ptb_cedrus_devices{handle}.link);
IOPort('Close', ptb_cedrus_devices{handle}.link);
end
end
% Clear out device struct:
ptb_cedrus_devices{handle} = [];
return;
function nrAvail = BytesAvailable(handle)
global ptb_cedrus_devices;
if ptb_cedrus_devices{handle}.driver == 0
% Matlabs serial() driver:
% Readout BytesAvailable subfield of device link object:
nrAvail = ptb_cedrus_devices{handle}.link.BytesAvailable;
else
if ptb_cedrus_devices{handle}.driver == 1
% OS/X + Matlab + SerialComm driver:
% All reads are non-blocking and there isn't any BytesAvailable
% command. We fetch all data that's currently available via
% non-blocking read and attach it to our own queue, then return
% the total number of bytes in the queue:
data = transpose(SerialComm('read', ptb_cedrus_devices{handle}.link));
ptb_cedrus_devices{handle}.recvQueue = [ptb_cedrus_devices{handle}.recvQueue data];
nrAvail = length(ptb_cedrus_devices{handle}.recvQueue);
end
if ptb_cedrus_devices{handle}.driver == 2
% IOPort driver:
nrAvail = IOPort('BytesAvailable', ptb_cedrus_devices{handle}.link);
end
end
if nrAvail > 0
% Store timestamp when queue was not empty:
ptb_cedrus_devices{handle}.lastTimeQueueNonEmpty = GetSecs;
end
return;
function data = ReadDev(handle, nwanted)
global ptb_cedrus_devices;
if ptb_cedrus_devices{handle}.driver == 0
% Matlabs serial() driver:
% Read via fread 'nwanted' bytes from link. Block until we get the
% wanted 'nwanted' bytes or until timeout / error:
data = transpose(fread(ptb_cedrus_devices{handle}.link, nwanted));
else
if ptb_cedrus_devices{handle}.driver == 1
% OS/X + Matlab + SerialComm driver:
% Call BytesAvailable to trigger read-in of data from serial
% port to our internal queue and to update the available stats,
% until at least the 'nwanted' bytes are available, or until
% the read operation times out after 2 seconds:
currtime = GetSecs;
timeout = currtime + 2;
while (BytesAvailable(handle) < nwanted) && (currtime < timeout)
% We are on OS/X, so waiting for 1 msec should suffice, no
% need to wait 4 msecs as on that other deficient OS:
currtime = WaitSecs(0.001);
end;
if currtime >= timeout
fprintf('Timed out: nwanted = %i, got %i bytes: %s\n', nwanted, BytesAvailable(handle), char(ptb_cedrus_devices{handle}.recvQueue));
fprintf('Read operation on response box timed out after 2 secs!\n');
data = [];
return;
end
% Have at least the nwanted bytes, so fetch the first nwanted
% bytes from queue:
data = ptb_cedrus_devices{handle}.recvQueue(1:nwanted);
% Dequeue them from queue:
if length(ptb_cedrus_devices{handle}.recvQueue) > nwanted
% Keep tail of queue:
ptb_cedrus_devices{handle}.recvQueue = ptb_cedrus_devices{handle}.recvQueue(nwanted+1:end);
else
% Nothing more in queue: Delete it.
ptb_cedrus_devices{handle}.recvQueue = [];
end
end
if ptb_cedrus_devices{handle}.driver == 2
% IOPort driver: Returns all data as data type double:
% fprintf('In read....\n');
[data, when, errmsg] = IOPort('Read', ptb_cedrus_devices{handle}.link, 1, nwanted);
if length(data) < nwanted
fprintf('Timed out: nwanted = %i, got %i bytes: %s\n', nwanted, length(data), char(data));
fprintf('Read operation on response box timed out after 1 secs! errmsg = %s\n', errmsg);
data = [];
return;
end
end
end
return;
function WriteDev(handle, data)
global ptb_cedrus_devices;
if ptb_cedrus_devices{handle}.driver == 0
% Matlabs serial() driver:
% Write data via fwrite: We provide our own '%s' formatting string
% to make sure that data is passed as-is, without any terminators
% (CR or LF or CR+LF) attached. This will block until send
% completion:
fwrite(ptb_cedrus_devices{handle}.link, char(data));
else
if ptb_cedrus_devices{handle}.driver == 1
% OS/X + Matlab + SerialComm driver:
% Write data - without terminator - via SerialComm:
SerialComm('write', ptb_cedrus_devices{handle}.link, double(data));
end
if ptb_cedrus_devices{handle}.driver == 2
% IOPort driver:
% Write data - without terminator:
% fprintf('In write....\n');
IOPort('Write', ptb_cedrus_devices{handle}.link, char(data), 1);
end
end
return;
function roundtrip = RoundTripTestDev(handle)
global ptb_cedrus_devices;
% Flush the queue:
FlushEvents(handle);
% Perform 100 measurement trials:
roundtrip = zeros(1,100);
for i=0:100
% Wait a bit between each trial:
WaitSecs(0.100);
% Send 'e4' code to initiate procedure:
WriteDev(handle, 'e4');
% Wait for receive completion:
while BytesAvailable(handle) < 1
end;
% Send echo, optimistically assuming we received a 'X':
WriteDev(handle, 'X');
% Get the really received byte and check:
if char(ReadDev(handle, 1))~='X'
error('Roundtrip test did not receive "X" char as expected!');
end
% Wait for receipt of timestamp:
while BytesAvailable(handle) < 4
end;
response = ReadDev(handle, 4);
if response(1)~='P' || response(2)~='T'
error('Roundtrip test did not receive "PT" marker as expected!');
end
response = double(response);
% We throw away the first trial:
if i > 0
roundtrip(i) = 0.001 * (response(3) + 256 * response(4));
end
end
% Store median and stddev of roundtrip time in device struct:
ptb_cedrus_devices{handle}.roundtriptime = median(roundtrip);
ptb_cedrus_devices{handle}.roundtripstddev = std(roundtrip);
return;
function [hosttime, devicetime, minwin] = queryBaseTimer(handle)
global ptb_cedrus_devices;
% Flush input buffer:
WaitSecs(1);
ClearQueues(handle);
WaitSecs(1);
% Switch to realtime priority if not already there:
oldPriority=Priority;
if oldPriority < MaxPriority('GetSecs')
Priority(MaxPriority('GetSecs'));
end
% Get porthandle:
blocking = 1;
ntrials = 5;
s = ptb_cedrus_devices{handle}.link;
t = zeros(2,ntrials);
% Perform up to ntrials trials:
for ic=1:ntrials
% Wait some random fraction of a millisecond. This will desync us
% from the USB duty cycle and increase the chance of getting a very
% small time window between scheduling, execution and acknowledge
% of the send operation:
WaitSecs(rand / 1000 + 1);
% Take pre-Write timestamp: Sync command not emitted before that time:
% Write sync command, wait 'blocking' for write completion, store
% completion time in t(2,ic). Send basetimer query command code 'e3':
[nw t(2,ic), errmsg, t(1,ic)] = IOPort('Write', s, 'e3', blocking);
% Wait for response from box, receive packet,
% then parse into raw timer value (in seconds):
devicetime = receiveAndParseTimePacket(handle);
% We know that query command emission has happened at some time
% after t(1,ic) and before t(2,ic). This by design of the USB
% standard, host controllers and operating system USB stack. This
% is the only thing we can take for granted wrt. timing, so the
% "time window" between those two timestamps is our window of
% uncertainty about the real host time when sync started. However,
% on a well working system without massive system overload one can
% be reasonably confident that the real emission of the sync
% command happened no more than 1 msec before t(2,ic). That is a
% soft constraint however - useful for computing the final estimate
% for hosttime, but nothing to be taken 100% for granted.
if nw~=2
% Send op failed!
fprintf('CedrusResponseBox: queryBaseTimer: Warning! Query token send operation to box failed!\n');
t(1,ic) = 0;
t(2,ic) = inf;
continue;
end
confidencewindow = t(2,ic) - t(1,ic);
if confidencewindow < 0.001
break;
end
% Next trial...
end
% Restore priority
if Priority ~= oldPriority
Priority(oldPriority);
end
% For each measurement, the time window t(2,ic)-t(1,ic) defines kind of
% a confidence interval for the "real" host system time when the sync
% command was emitted. The measurement with the smallest time window is
% the most accurate one. Find it and use it:
minwin = t(2,ic) - t(1,ic);
% On OS/X or Linux we could easily do with 2 msecs, as a 1.2 msecs
% minwin is basically never exceeded. On MS-Windows however, 2.x
% durations are not uncommon, so we need to slack this to 3.
if minwin > 0.002
fprintf('CedrusResponseBox: queryBaseTimer: Warning! Confidence interval for clock sync is %f msecs - More than 2 msecs!\n', minwin);
end
% If the 'minwin' window is smaller than 1 msec, we subtract 0.5 the
% length of it from the t(2,idx) timestamp as best estimate for
% hosttime -- reasonable assuming a uniform distribution in the
% 'minwin' interval. If 'minwin' is more than 1 msecs, we assume it
% happened 0.5 msecs before t(2,idx) -- taking advantage of the
% soft-constraint that the real write usually happens within 1 msec of
% t(2,idx) on a normally loaded and well working system:
hosttime = t(2,ic) - (min(minwin, 0.001)/2);
WaitSecs(0.2);
FlushEvents(handle);
WaitSecs(0.2);
return;
% Reads raw basetimer response packet from box, converted to seconds, but
% not corrected for receive latency etc. Query command must have been sent
% by calling code!
function rawBaseTime = receiveAndParseTimePacket(handle)
% Read all 6 bytes of basetimer response packet from box:
response = ReadDev(handle, 6);
if length(response)~=6
% Did not receive 6 bytes - This should not happen!
error('In receiveAndParseTimePacket: Received too short (or no) response packet from box!');
end
% Check bytes 1:2 for correct values 'e3':
if char(response(1))~='e' || char(response(2))~='3'
% Failed!
error('In receiveAndParseTimePacket: Received invalid response packet [Not starting with "e3"] from box!');
end
% Extracts bytes 3-6 and is the time elapsed in milliseconds since the
% base timer was last reset.
%
% For more information about the use of XID timers refer to
% http://www.cedrus.com/xid/timing.htm
% Conver to seconds:
response = double(response);
rawBaseTime = 0.001 * (response(3)+(response(4)*256)+(response(5)*65536) +(response(6)*(65536*256)));
return;
function ptbTime = mapRTTimerToPTBTime(rtt, handle)
global ptb_cedrus_devices;
if ptb_cedrus_devices{handle}.baseToPtbOffset ~= 0
% rtt is the parsed timevalue (already mapped from msecs to seconds),
% as received in a event packet from the box. We map it to ptbTime by
% adding the offset between GetSecs time and device RTT time, as
% estimated by last calibrated RTTReset():
ptbTime = ptb_cedrus_devices{handle}.baseToPtbOffset + rtt;
else
% Missing clock sync. Return "invalid" result:
ptbTime = nan;
end
return;
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