— 5 —
NOMENCLATURE OF KEYS
POWER SUPPLY CIRCUIT
The power supply circuit generates five voltages as shown in the following table. VDD voltage is always
generated. The others are controlled by POWER signal from the CPU.
RESET CIRCUIT
When batteries are set or an AC adapter is connected, the reset IC provides a low pulse to the CPU. The
CPU then initializes its internal circuit, and clears the working storage RAM.
When the power switch is pressed, the CPU receives a low level signal. The CPU sends POWER signal
to the power supply circuit, also sends a reset signal to the DSP.
When the keyboard is powered by batteries and no operation is made for six minutes, CPU drops signal
POWER to shut all the voltage except VDD off.
C2
C#2 D#2
F#2 G#2 A#2
C#3 D#3
F#3 G#3 A#3
C#4 D#4
F#4 G#4 A#4
C#5 D#5
F#5 G#5 A#5
C#6 D#6
F#6 G#6 A#6
C#7 D#7
F#7 G#7 A#7
D2 E2 F2 G2 A2 B2
C1 D1 E1 F1 G1 A1 B1
A0 B0
C3 D3 E3 F3 G3 A3 B3
C#1 D#1
F#1 G#1A#1
A#0
C4 D4 E4 F4 G4 A4 B4 C5 D5 E5 F5 G5 A5 B5
D6 E6 F6 G6 A6 B6
C6
C7 D7 E7 F7 G7 A7 B7 C8
Reset IC
IC1
RN5VD35AA
DSP
LSI1
HG51B277FB
VDD
Reset signal
To power supply circuit
VDD
Battery set
RESET
VDD
Power switch
NMI
POWER
PLE
CPU
LSI4
GT913F
SCKO
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Summary of Contents for CPS-85
Page 13: ...13 SCHEMATIC DIAGRAMS Main PCB JCM423 MA1M 1 2 8 7 6 5 3 4...
Page 14: ...14 Sub PCBs JCM423 MA2M MA3M MA4M 10 9...
Page 15: ...15 Console PCBs JCM423 CN1M CN2 CN3M...
Page 16: ...16 Keyboard PCB JCM886T KY1M...
Page 17: ...17 Keyboard PCB JCM886T KY2M...
Page 18: ...18 Keyboard PCB JCM886T KY3M...
Page 20: ...20 35 33 35 31 30 34 32 SP 2...
Page 24: ...8 11 10 Nishi Shinjuku Shinjuku ku Tokyo 160 Japan Telephone 03 3347 4926 MA0700571A...
