Soyo SY-K7VTA User Manual

buffers and sixteen levels (doublewords) of prefetch buffers are included

for concurrent PCI bus and DRAM/cache accesses.  The chip also

supports enhanced PCI bus commands such as Memory-Read-Line,

Memory-Read-Multiple and Memory-Write-Invalid commands to

minimize snoop overhead.  In addition, advanced features are supported

such as snoop ahead, snoop filtering, L1/L2 write-back forward to PCI

master, and L1/L2 write-back merged with PCI post write buffers to

minimize PCI master read latency and DRAM utilization.  Delay

transaction and read caching mechanisms are also implemented for further

improvement of overall system performance.
Ø VT82C686A

The VT82C686A PSIPC (PCI Super-I/O integrated Peripheral Controller)

is a high integration, high performance, power-efficient, and high

compatibility device that supports AMD and non-AMD based processor to

PCI bus bridge functionality to make a complete Microsoft PC99-

compliant PCI/ISA system In addition to complete ISA extension bus

functionality, the VT82C686A includes standard AMDligent peripheral

controllers:

1) Master mode enhanced IDE controller with dual channel DMA engine

and interlaced dual channel commands. Dedicated FIFO coupled with

scatter and gather master mode operation allows high performance

transfers between PCI and IDE \devices. In addition to standard PIO and

DMA mode operation, the VT82C686A also supports the UltraDMA-33

standard to allow reliable data transfer rates up to 33MB/sec throughput.

The VT82C686A also supports the UltraDMA-66 standard. The IDE

controller is SFF-8038I v1.0 and Microsoft Windows-family compliant.

2) Universal Serial Bus controller that is USB v1.1 and Universal HCI

v1.1 compliant. The VT82C686A includes the root hub with four

function ports with integrated physical layer transceivers. The USB

controller allows hot plug and play and isochronous peripherals to be

inserted into the system with universal driver support. The controller

also implements legacy keyboard and mouse support so that legacy