开源IP核

国家IP核库：   http://www.ipmall.org.cn/?action-ipcore

altera   NIOS II:    http://www.altera.com/products/ip/processors/nios/nio-index.html

                          doc:  http://www.altera.com.cn/devices/processor/nios2/ni2-index.html

OpenCores:     http://opencores.org/projects

openRISC:     

                          OpenRisc是OpenCores组织提供的基于GPL协议的开放源代码的RISC

                          http://baike.baidu.com/view/1699210.htm