Mem(String name, String desc, int extraPorts) {
super(name, desc);
currentInstanceFiles = new WeakHashMap<Instance,File>();
setInstancePoker(MemPoker.class);
setKeyConfigurator(JoinedConfigurator.create(
new BitWidthConfigurator(ADDR_ATTR, 2, 24, 0),
new BitWidthConfigurator(DATA_ATTR)));
setOffsetBounds(Bounds.create(-140, -40, 140, 80));
}