Epson RS-353, Service Manual

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Outline of function
*
When the power turns on, the driver board resets the reset signal which is controlled
by and the CPU reads the program from flash ROM and write it into RAM
Then the CPU sets functions according to the program and indicates the
initial image.
* There is a digital video at the interface between the video board to generate a
timing of indicating the image data received or execute the data bit converting (A/D)
for writing the received analog image data to S-RAM.
* Memory controller executes read/write of indication data to S-RAM.
signals (Analog/Digital) provided through the interface board are once stored
video RAM.
Video
in the
* The data stored in the S-RAM is converted in analog signals by D/A converter.
The output will be divided into 8 bits for each of R/G/B light valves by amplitude circuit
and clamp circuit.
* Digital R/G/B input signal is synchronized its indication data and the control timing by
three states buffer before output to the driver board.
* Analog R/G/B signal is amplified by the amplitude circuit and converted its individual
signals into data of 7 bits each by A/D converter circuit before output to the driver
board.
Analog R/G/B output signals will transmit the different ways in each case of the
analog input and the digital input.
(1) in case of analog R/G/B
The output of video amplitude will be output via video buffer.
(2) in case of digital R/G/B
The digital indication signals output from the driver board is once
converted into analog signals by the circuit and the D/A converter before
output through the video buffer.
* Audio input is controlled its volume (Laud/Quiet/Mute) by the audio control circuit and
amplified by the audio amplitude circuit before output to the speaker unit (Right/Left)
through the driver board.
* Audio input signal is transferred to the audio output interface via audio control circuit.
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