For new projects, we recommend using this simple matlab function to synchronise with the scanner pulses. For existing projects we continue to support ScannerSynchClass, which is described further below.
ScannerSynch provides an interface for National Instruments PCI 6503 card used to capture all pulses (scanner synch pulse and button pulses alike) when using MATLAB.
For more information, type in MATLAB
help ScannerSynchClass
N.B.: National Instruments PCI 6503 card does not monitor pulses in the background, so you have to make sure that you wait for any pulse before it comes!
Any problems, report them to Johan Carlin.
Contents
ScannerSynch is available on all relevant PCs (StimPCs, "mimic" PC). You can check out a local version for testing from our github repo.
SSO = ScannerSynchClass;
SSO = ScannerSynchClass(1); % emulate scanner synch pulse
SSO = ScannerSynchClass(0,1); % emulate button box
SSO = ScannerSynchClass(1,1); % emulate scanner synch pulse and button box
ScannerSynchClass has a destructor, which is automatically triggered if the object is deleted (e.g. clear, returning function). If you use a script, however, it does not perform any auto-clear, so you have to destroy the object manually:
SSO.delete;
SSO.SetSynchReadoutTime(0.5); % make sure that you do not detect the same pule twice
SSO.TR = 2; % allows detecting missing pulses
while SSO.SynchCount < 10 % polls 10 pulses
SSO.WaitForSynch;
fprintf('Pulse %d: %2.3f. Measured TR = %2.3fs\n',...
SSO.SynchCount,...
SSO.TimeOfLastPulse,...
SSO.MeasuredTR);
end
SSO.SetSynchReadoutTime(0.5); % make sure that you do not detect the same pule twice
SSO.TR = 2; % allows detecting missing pulses
while SSO.SynchCount < 10 % until 10 pulses
WaitSecs(Randi(100)/1000); % in every 0-100 ms ...
if SSO.CheckSynch(0.01) % ... waits for 10 ms for a pulse
fprintf('Pulse %d: %2.3f. Measured TR = %2.3fs. %d synch pulses has/have been missed\n',...
SSO.SynchCount,...
SSO.TimeOfLastPulse,...
SSO.MeasuredTR,...
SSO.MissedSynch);
end
end
SSO.SetButtonReadoutTime(0.5); % block individual buttons for 0.5s after button press so we will not detect the same button press twice
% SSO.SetButtonBoxReadoutTime(0.5); % block the whole buttonbox for 0.5s after button press
% SSO.Keys = {'f1','f2','f3','f4'}; % emulation Buttons #1-#4 with F1-F4
n = 0;
% SSO.BBoxTimeout = 1.5; % Wait for button press for 1.5s
% SSO.BBoxTimeout = -1.5; % Wait for button press for 1.5s even in case of response
SSO.ResetClock;
while n ~= 10 % polls 10 button presses
SSO.WaitForButtonPress; % Wait for any button to be pressed
% SSO.WaitForButtonRelease; % Wait for any button to be released
% SSO.WaitForButtonPress([],2); % Wait for Button #2
% SSO.WaitForButtonPress(2); % Wait for any button for 2s (overrides SSO.BBoxTimeout only for this event)
% SSO.WaitForButtonPress(-2); % Wait for any button for 2s even in case of response (overrides SSO.BBoxTimeout only for this event)
% SSO.WaitForButtonPress(2,2); % Wait for Button #2 for 2s (overrides SSO.BBoxTimeout only for this event)
% SSO.WaitForButtonPress(-2,2); % Wait for Button #2 for 2s even in case of response (overrides SSO.BBoxTimeout only for this event)
n = n + 1;
fprintf('At %2.3fs, ',SSO.Clock);
fprintf('Button %d ',SSO.LastButtonPress);
fprintf('pressed: %2.3fs\n',SSO.TimeOfLastButtonPress);
end