The MAC-1G/MAC is a synthesizable HDL core of a high-speed LAN controller. It implements Carrier Sense Multiple Access with Collision Detection (CSMA/CD) algorithms defined by the IEEE 802.3 standard for media access control over the 10Mbps, 100Mbps and 1Gbps Ethernet. Communication with an external host is implemented via a set of Control and Status Registers and the DMA controller for external shared RAM memory. For data transfers the MAC-1G/MAC operates as
a DMA master. It automatically fetches from transmit data buffers and stores receive data buffers into external RAM with minimum CPU intervention. The linked list management enables the use of various memory allocation schemes. There is an interface for external dual port RAMs serving as configurable FIFO memories and there are separate memories for transmit and receive processes. Using the FIFOs additionally isolates the MAC-1G/MAC from an external host and provides resolution in case of latency of an external bus.
Application
Network Interface Cards (NICs)
Routers, switching hubs