ScanImage 2019 : Photostimulation Breakout Box and Sample Code

Created by Lawrence Niu on May 07, 2019

Do I need to have the SCB-19 breakout box (I already have three breakout boxes (BNC-2090A) that are connected to the PXI Chassis)?

Could I use the BNC-2090A breakout boxes instead of an SCB-19?

 

There are a couple of ways to do this:

  1. If you use the FPGA to detect the rising edge of the trigger-> then you need the additional breakout box
  2. Use a DAQmx digital input task that is synchronized to the acquisition. This task samples the trigger with a predefined rate (say 10kHz) and saves the data to disk.

Method 1 is built into ScanImage and requires the additional breakout box.

Method 2 you can reuse the DAQ breakout boxes, but you will need to write a bit of (fairly simple) code to set up the digital input task. Sample code is provided below.

function captureDigitalInput(tf)

persistent hTask

if nargin < 1

tf = true;

end

if tf

deviceName = 'PXI1Slot4';
line = 'port0/line0';
sampleRate = 1000; % Hz

if ~isempty(hTask) && isvalid(hTask)

hTask.delete();

end

hTask = most.util.safeCreateTask('My digital input Task');

hTask.createDIChan('PXI1Slot4',line);
hTask.cfgSampClkTiming(sampleRate,'DAQmx_Val_ContSamps');

sampleRate = hTask.sampClkRate;
fprintf('Actual sample rate: %f\n',sampleRate);

% synchronize to scanimage
set(hTask,'sampClkTimebaseRate',10e6);
set(hTask,'sampClkTimebaseSrc',['/' deviceName '/PXI_Clk10']);

% set up trigger
hTask.cfgDigEdgeStartTrig('PXI_Trig1'); % frame clock is exported to PXI_Trig6 on the back plane

% setup callback
everyNSamples = 1000;
hTask.registerEveryNSamplesEvent(@everyNSamplesCallback,everyNSamples,true);

hTask.start();

else

hTask.clear();

end

end

 

function everyNSamplesCallback(obj,src,evt)

persistent hPlot

if isempty(hPlot) || ~isvalid(hPlot)

hFig = figure;
hAx = axes();
hPlot = plot(hAx,src.data);

else

hPlot.XData = 1:length(src.data);
hPlot.YData = src.data;

end

end