User Guide

8965 N/B Maintenance

h) Integrated bus-mastering dual full-duplex direct-sound AC97-link-compatible sound system.

I) Plug and Play controller that allows complete steerability of all PCI interrupts and internal interrupts / DMA

channels to any interrupt channel. One additional steerable interrupt channel is provided to allow plug and

play and reconfigurability of onboard peripherals for Windows family compliance.

The VT8235 Version CE also enhances the functionality of the standard ISA peripherals. The integrated interrupt

controller supports both edge and level triggered interrupts channel by channel. The integrated DMA controller

supports type F DMA in addition to standard ISA DMA modes. Compliant with the PCI-2.2 specification, the

VT8235 Version CE supports delayed transactions and remote power management so that slower ISA peripherals do

not block the traffic of the PCI bus. Special circuitry is built in to allow concurrent operation without causing dead

lock even in a PCI-to-PCI bridge environment. The chip also includes eight levels (double words) of line buffers from

the PCI bus to the ISA bus to further enhance overall system performance.

1.2.5 AC’97 Audio System: Advance Logic, Inc, ALC655

The ALC655 is a 16-bit, full duplex AC'97 2.3 compatible six channels audio CODEC designed for PC multimedia

systems, including host/soft audio and AMR/CNR based designs. The ALC655 incorporates proprietary converter

technology to meetperformance requirements on PC99/2001 systems. The ALC655 CODEC provides three pairs of

stereo outputs with 5-Bitvolume controls, a mono output and multiple stereo and mono inputs, along with flexible

mixing, gain and mute functions toprovide a complete integrated audio solution for PCs. The digital interface circuitry

of the ALC655 CODEC operates from a 3.3V power supply for use in notebook and PC applications. The ALC655

integrates 50mW/20ohm headset audio amplifiers at Front-Out and Surr-Out, built-in 14.318M 24.576MHz PLL and

PCBEEP generator, those can save BOM costs. The ALC655 also supports the S/PDIF input and output function,

which can offer easy connection of PCs to consumer electronic products, such as AC3 decoder/speaker and mini disk

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