Casio GZ-500 manual Button Matrix, Power Supply Circuit, Reset Circuit, Name Voltage For operation

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BUTTON MATRIX

 

KI1

KI2

KI3

KI4

KI5

 

 

 

 

 

 

KO0

3

0

2

1

 

 

 

 

 

 

 

KO1

Control

Demo

Effect

MIDI

 

 

 

 

 

 

 

KO2

+

9

7

8

 

 

 

 

 

 

 

KO3

6

-

5

4

 

 

 

 

 

 

 

KO4

Tone

MIDI

Channel

Octave

Modulation

Channel

On/Off

Shift

 

 

 

 

 

 

 

 

 

POWER SUPPLY CIRCUIT

The power supply circuit generates six voltages as shown in the following table. VDD voltage is always generated. The others are controlled by APO signal output from the CPU.

Name

Voltage

For operation of

 

 

 

VDD

+5 V

CPU, Reset IC, Working storage RAM

 

 

 

DVDD

+5 V

DSP, Key touch LSI, Sound source ROM, Effect RAM, KO siginal generator

 

 

 

AVDD

+5V

DAC, Filter

 

 

 

LVDD

+4.5 V

LED Driver

 

 

 

VCC

+9 V

Power amplifier, Pilot lamp

 

 

 

VC

+9 V

Power amplifier

 

 

 

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 pulse of POWER signal. The CPU provides APO signal to the power supply circuit and raises RESET signal to +5V to reset the DSP, the key control- ler and the KO signal generator.

Battery set

VDD

 

VDD

 

RESET

 

Reset IC

CPU

IC105

LSI106

RH5VL36AA

HD6433298A42F

POWER

-NMI

From power switch

 

APO

P42

 

To power supply circuit

 

 

DVDD

 

DVDD

 

 

 

 

 

 

 

KO Signal Generator

 

DSP

IC102

 

LSI102

TC74HC174AF

 

HG51B155FD

 

 

 

 

 

-RESET

 

VDD

 

DVDD

 

 

 

 

 

 

 

 

Working Strage RAM

 

Key Controller

LSI105

 

LSI107

SRM2264LM90

 

HG52E35P

 

 

 

 

 

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Image 10
Contents GZ-500 Contents SpecificationsInitial settings Setting UP the KeyboardSetting Setting operation OperationMidi Message Setting Setting operation Initial settings in The General Midi systemTransmitting Midi Messages Selecting a Midi channel 1. Press the Midi button Receiving Midi Messages Initial settings of Midi control changeSetting on/off of a Midi channel Transmitting a digital effect typeTransmittable Messages Receivable MessagesBlock Diagram KC7Circuit Description KEY MatrixButton Matrix Power Supply CircuitReset Circuit Name Voltage For operationDigital Signal Processor LSI102 HG51B155FD Pin No Terminal In/Out FunctionCE1, Trsb Block diagram of DSP and DAC circuit GND4DAC LSI104 UPD6376GS KEY Controller LSI107 HG52E35PFilter Block Power Amplifier IC402 LA4598 LED DrivingMajor Waveforms Schematic Diagrams Main PCB JCM715-MA1M Console PCBs JCM715-CN1M/2M/3M Keyboard PCBs M616T-KY1M/KY2M Exploded View Parts List Amp./Volume PCBs FOB Japan Code No Parts Name Specification Yen Unit Price MA0800751A