The present invention provides circuitry and methods for sharing I/O pins between a programmable logic portion and an embedded processor portion of a chip. The circuits in the programmable logic portion and the embedded processor portion can access data signals from and send data signals to the same...http://www.google.com.hk/patents/US7446561?utm_source=gb-gplus-share專利 US7446561 - I/O circuitry shared between processor and programmable logic portions of an integrated circuit
