Plot binary data from serial port

I want to plot the bit data signal from the serial port. I use the command fread as Matlab say that fread is the funtion to read binary data. But when I use fread, I got numbers like 10,41,83,etc instead of 0 and 1. I want to view the signal as 0 and 1 so the plot is like squarewave. What am I supposed to do?

Here are my codes:

x=0:0.01:10;

y=fread(s);

cla;drawnow;

h=plot(handles.axes1,x(1),y(1));grid on; hold on; legend data;

for idx = 1 : length(x);

set(h,'xdata',x(1:idx),'ydata',y(1:idx));drawnow; end;

% s is the serial.

[Lorenzo Luengo]

you mean something like view the serial stream?? maybe you can try this using dec2bin function.