Add sample.lua for the common code

sample.lua

@@ -0,0 +1,22 @@
+position = mem.position
+if position == nil then
+	position = 0
+end
+position = position + 1
+mem.position = position
+
+if pin.b then
+	if notes[position] == nil then
+		port = {a=false, b=false, c=false, d=false}
+	elseif note[position] == 1 then
+		port = {a=true, b=false, c=false, d=false}
+	elseif note[position] == 2 then
+		port = {a=false, b=true, c=false, d=false}
+	elseif note[position] == 3 then
+		port = {a=false, b=false, c=true, d=false}
+	elseif note[position] == 1 then
+		port = {a=false, b=false, c=false, d=true}
+	end
+else
+	mem.position = 0
+end