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control and then processed and converted into the necessary analogue signals to drive the video output displays and sound system. The VIDC20 can handle many more display and sound formats than the original VIDC1 chip found in the
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Data from the buffer is read at a programmable rate and passed to an 8-bit/16-bit DAC. The DAC uses the stereo image registers to convert the digital samples to a stereo analogue sample which is sent to the computer's internal amplifier
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data controller controls a 32-pixel-wide, and an unlimited number of pixels high, cursor. The pixels can be transparent or can be any three colors picked from the possible 16 million available colors.
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The palette has 256 28-bit-wide registers: 8 red bits, 8 green bits, 8 blue bits and 4 bits for external data. The output is then converted by three 8-bit
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channels using time division multiplexing to synthesize left and right outputs. Each channel can be assigned a stereo position (between left to right).
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It also contains a phase comparator which allows for a single clock to generate all the required frequencies for any display mode.
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sounds are provided by the VIDC20 chip. The chip can work with 1, 2, 4 or 8
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A VIDC20 chip controls both the computer's video and sound.
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if installed in the machine, otherwise it reads from
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The data is read from the 64-bit ARM data bus using
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