Video; Audio - Aristocrat USA MAV500/MKVI Service Manual

Main Board
I/O Expansion Port Interrupts.
The I/O expansion port has 4 interrupts: IL0, IF, FL, and FH0 (schematic IO_IN).
Pull-up/down resistors pull unused interrupts to their inactive state. EMC filtering is
provided to prevent spurious interrupts.
SH-4 Timers
The SH-4 has four built-in timers able to time intervals. The timers are controlled by
a 33 Hz clock. Three primary clocks exist within the board: 14.318 Hz, 32.768 Hz,
and 33 Hz. All other clocks are derived from these primaries.
Primary Clock. The SH-4 uses a primary clock of 33 Hz that is internally
•
doubled to provide 66 Hz for the Bus interfaces. The clock has a tight duty cycle
specification of 66 Hz. The primary clock is multiplied by 6 to create 198 MHz
for the SH
Bus Clock. The CPU SH-4 core and memory controller has an optional clock
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input to allow higher speed operation.
Video Clock. The video clock is 14.318 MHz which is provided by an external
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crystal.
Time Clock. The real time clock chip uses a 32.768 kHz crystal to keep time.
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10.4.2

Video

The Main Board functions with an on-board video graphics controller to provide high
performance for extended graphics and video processing capabilities.
The controller, the PowerVR 250 (code-named PMX1-LC), has been produced
through a joint venture of VideoLogic and NEC who have now released the advanced
device with a 2D and a 3D engine, a VMI video input bus and digital interface.
The device is able to deliver VGA-standard displays of 640 x 480 in 24 bits/pixel
with a video vertical frequency of 60 Hz. It is supported with a 32-Mbytes SDRAM
array and is connected to the 22 MHz PCI.bus. High quality animation sequences are
achieved through the improved appearance of motion resulting from the updating of
displays at 30 frames per second − twice that of earlier Aristocrat gaming machines.
10.4.3

Audio

The audio system uses an audio amplifier, a 16
a conversion filter and EPROM space to store digitised, compressed, sampled audio.
The process converts the digital audio using the DAC, applies a filter to remove any
noise and then amplifies the output. Note that volume control, although generated by
hardware, is under software control. There are three parts to the production of audio:
DMA (Direct Memory Access), DAC and Power Amplification.
10-12
This document contains confidential information which is proprietary to ATI. It may not be disclosed to any unauthorized parties,
and it may not be copied. All rights reserved. © Copyright (ATI) Aristocrat Technologies, Inc. 2002
4 clock.
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USA MAV500/MKVI Service Manual
bit digital-to-analog converter (DAC),
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