Casio Understanding the Keyboard Block Diagram of the CTK-230

BLOCK DIAGRAM

Keyboard		Buttons
KI0~KI6	KID0~KID6	KOD8~KOD12

LCD-E LCD-RW LCD-RS MPU ML6556 IC202

LCD

DB4~DB7 APO

PowerAmp.	LA4227 IC201	VCC DVDD AVDD	SupplyCircuit	~Q203,D204
Phones/Output		VC	Power	Q201
			IN
Speaker (L)	Speaker (R)		DC+9V

Power Switch

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