Service manual

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ESS ES1788 AudioDrive
The ES1788 AudioDrive can record, compress, and playback voice, sound and music
with built-in mixer controls. It consists of an embedded microprocessor, a game
compatible 16-bit stereo A/D and D/A, music 16-bit stereo D/A, 20-voice 72 operator FM
music synthesizer, MIDI serial port compatible with MPU401 UART mode, dual joystick
timers, hardware volume control, DMA control, and ISA bus interface logic. A DSP serial
interface allows an external DSP to take over analog resources such as the D/A or A/D
converters. Control of I/O address, DMA, and interrupt selection is controlled by system
software. Interface to analog inputs is extremely simple. There are stereo inputs for CD-
audio, line-in, and an external music synthesis chip or TV, and a mono microphone
input to an internal pre-amp. A digital PC speaker input is converted to an analog signal
with volume control and is available as an analog output signal. Advanced power
management features such as suspend/resume to disk, self timed power down, auto-
wakeup, and partial power-down are supported. The ES1788 AudioDrive has a 6 bit
master volume control with 64 total steps.
The ES1788 AudioDrive is compatible with Sound Blaster PRO version 3.01 voice and
music functions as documented in the Sound Blaster Series Developer Kit.