Hi, I would like to generate a colored screen with a 4

Hi, I would like to generate a screen with a 4 square colored that flash or change color at a frequency chosen, on a black background I tried with Psychtoolbox, but I can not create it. Can you suggest lines of code that do this? Thanks in advance for the help. Greetings, Danilo.

Answer 1

[Chaya N]

Create a simple GUI with four blocks for the colors.

http://mathworks.com/videos/creating-a-gui-with-guide-68979.html

[Danilo Esposito]

Thank you for your answer, but I would that these squares were flashing at a precise frequency. I need to generate SSVEP EEG signals. can you help me? Thanks again

[Walter Roberson]

Flashing at a precise frequency is not something you are going to be able to do in pure MATLAB. You are going to need the facilities of Psychtoolbox, which is (for example) able to tie in to the screen refresh signal.

[Danilo Esposito]

When I try to use the Psychtoolbox package gives me this error

[Chaya N]

If you will be running this program on external hardware (like one of the TDT systems), then you may be able to sample the frequency from the external hardware itself. Doing it purely in MATLAB is not possible unless you have some other signal you are synchronizing it to.

[Danilo Esposito]

OK, thanks for your help. Best regards, Danilo.