The Realtek RTL8401-GR Fast Ethernet controller combines an IEEE 802.3 10/100Base-T compliant Media Access Controller (MAC), PCI Express bus controller, and embedded One-Time-Programmable (OTP) memory. With state-of-the-art DSP technology and mixed-mode signal technology, the RTL8401-GR offers high-speed transmission over CAT 5 UTP cable or CAT 3 UTP (10Mbps only) cable. Functions such as Crossover Detection & Auto-Correction, polarity correction, adaptive equalization, cross-talk cancellation, echo cancellation, timing recovery, and error correction are implemented to provide robust transmission and reception capability at high speeds.
The device supports the PCI Express 1.1 bus interface for host communications with power management, and is compliant with the IEEE 802.3u specification for 10/100Mbps Ethernet. It also features a built-in PCI Express 1.1 compliant card reader controller; integrating a PCI Express Transceiver, regulators, and memory card access units into a single ship.
The RTL8401-GR supports Memory Stick, Memory Stick Pro, Memory Stick PRO-HG Duo, Secure Digital, Multi-Media Card, and xD-Picture Card in a 1-LUN (Logical Unit Number) configuration (which means only one of these memory cards can be inserted into the RTL8401-GR system at one time). The device also supports an auxiliary power auto-detect function, and will auto-configure related bits of the PCI power management registers in PCI configuration space. The RTL8401 features embedded One-Time-Programmable (OTP) memory to replace the external EEPROM (93C46).
Advanced Configuration Power management Interface (ACPI)—power management for modern operating systems that are capable of Operating System-directed Power Management (OSPM)—is supported to achieve the most efficient power management possible. PCI MSI (Message Signaled Interrupt) and MSI-X are also supported.
In addition to the ACPI feature, remote wake-up (including AMD Magic Packet and Microsoft® Wake-up frame) is supported in both ACPI and APM (Advanced Power Management) environments. To support WOL from a deep power down state (e.g., D3cold, i.e., main power is off and only auxiliary exists), the auxiliary power source must be able to provide the needed power for the RTL8401-GR.
The RTL8401-GR is fully compliant with Microsoft® NDIS5, NDIS6 (IPv4, IPv6, TCP, UDP) Checksum and Segmentation Task-offload (Large send and Giant send) features, and supports IEEE 802 IP Layer 2 priority encoding and IEEE 802.1Q Virtual bridged Local Area Network (VLAN). The above features contribute to lowering CPU utilization, especially benefiting performance when in operation on a network server.
The RTL8401-GR supports Receive Side Scaling (RSS) to hash incoming TCP connections and load-balance received data processing across multiple CPUs. RSS improves the number of transactions per second and number of connections per second, for increased network throughput.
The device also features inter-connect PCI Express technology. PCI Express is a high-bandwidth, low pin count, serial, interconnect technology that offers significant improvements in performance over conventional PCI and also maintains software compatibility with existing PCI infrastructure. The device embeds an adaptive equalizer in the PCIe PHY for ease of system integration and excellent link quality. The equalizer enables the length of the PCB traces to reach 20 inches.
The RTL8401-GR is suitable for multiple market segments and emerging applications, such as desktop, mobile, workstation, server, communications platforms, and embedded applications.
The RTL8401-GR supports the Deep Slumber (DSM) V2 power saving feature. See the separate DSM application notes for details.