User’s Manual

The VT8251 interfaces to the companion North Bridge chip through the Ultra V-Link interface with up to 1 GB/sec data transferrate. Two 1-Lane PCI Express ports are provided for high-speed peripheral devices. The VT8251 allows combining the two 1-Lane PCI-E ports into a 2-Lane port for peripheral that requires extra bandwidth. For standard 33 MHz PCI devices, the VT8251 supports up to seven PCI master devices.

In addition, the VT251 integrates extensive peripheral controllers for modern, state-of-the-art PC systems:

•Four-port Serial ATA / RAID Controller

The Serial ATA / RAID controller supports RAID Level 0, RAID Level 1, RAID Level 0+1 and JBOD, and complies with Serial ATA Specification Revision 1.0, and Serial ATA II specification. The Serial ATA controller is configurable and can be configured to support either 4 Serial ATA II master ports or 2/2 Serial ATA I master/slave ports with 3.0 Gbits/sec and 1.5 Gbits/sec data transfer rates.

•Dual-channel Enhanced IDE Controller

In addition to standard PIO and DMA mode operation, the VT8251 also supports the UltraDMA-133, 100, 66, and 33 standards, allows reliable data transfer rates up to 133 MB/sec. The IDE controller is SFF-8038i v1.0 and Microsoft Windows-family compliant.

•IEEE 802.3 compliant 10 / 100 Mbps Ethernet MAC with MII interface to external PHYceiver

•Universal Serial Bus Controller with eight USB 2.0 ports

The VT8251 USB controller includes four USB 1.1 root hubs, a USB 2.0 root hub, and eight USB 2.0 ports with integrated physical layer transceivers. Hot plug and isochronous peripherals are supported. Support of legacy keyboard and mouse is implemented so that legacy software could run transparently.

•Integrated AC97-link Controller

The AC-link controller can be used to attach an audio codec (AC), a modem codec (MC), an audio modem codec (AMC) or a combination of ACs and a single MC.

•Full System Management Bus (SMBus) interface

•Keyboard controller with PS/2 mouse support

•Real Time Clock with 256 bytes extended CMOS

In addition to the standard ISA RTC functionality, the integrated RTC also includes the date alarm, century field and other enhancements for compatibility with the ACPI standard.

•Notebook-class, sophisticated Power Management Unit compliant with ACPI and legacy APM requirements

Multiple sleep states (POS, STR and STD) are supported with hardware automatic wake-up. Additional functionality includes event monitoring, CPU clock throttling and stop, PCI bus clock stop control, modular power, clock and leakage control, hardware-based and software-based event handling, general purpose I/O, chip select and external SMI.

ECM-3711 Series User’s Manual 17