global stop;
stop = 1;

dd=giottoopen('LPT1');
fig=figure(1); 

im=giottograb(dd);
imshow(im,[]); 
s = uimenu('Label','STOP','Callback','stop=0;');

set(fig,'BackingStore','off');
set(fig,'DoubleBuffer','on')
set(fig,'Position',[100 100 size(im,2)*2 size(im,1)*2]);

while(stop)
   im=giottograb(dd);
   set(get(gca,'children'),'cdata',im);
   
   drawnow;
end;