t=0:pi/200:2*pi;
r=0.3;
x=r*cos(t);
y=r*sin(t);
h=plot(0,0);
hold on
delete(h)

for j=1:2:8
	plot([j j],[0 6],'k')
end

for i=1:3
	plot([0 8],[2*i-1 2*i-1],'k')
	for j=1:2:8
		fill(x+j,y+2*i-1,'w','edgecolor','w')
	end
end

fill([0 8 8 0],[0 0 -6 -6],'k')
for j=1:2:8
	plot([j j],[0 -6],'w')
end

for i=1:3
	plot([0 8],[-2*i+1 -2*i+1],'w')
	for j=1:2:8
		fill(x+j,-(y+2*i-1),'k','edgecolor','k')
	end
end

set(gcf,'color','w')
axis off
axis equal
hold off
