This application note describes a TCP/IP protocol stack demonstration running on Renesas Electronics’ RX62N MCU device.  RX62N has an integrated Ethernet peripheral capable of running at 10/100 Mbps in half or full duplex modes.  The Ethernet peripheral consists of an Ethernet controller and a dedicated Ethernet direct memory access controller. The Ethernet controller is fully compliant with IEEE 802.3 MAC layer standard and supports Media Independent Interface (MII) and Reduced Media Independent Interface (RMII) connecting to a physical device.  The Ethernet direct access memory controller achieves efficient bus utilization through the use of dedicated DMA data transfers between the Ethernet peripheral and the system RAM.