Casio CTK-401 Electronic Keyboard User Manual


 
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BLOCK DIAGRAM
CPU
MSM 6755B-17
LSI1
Keyboard
Buttons
LCD
LCD Driver
SED1278F0A
LSI3
Reset IC
IC1
Oscillator
X1, Q1
Power Supply Circuit
Q101 ~ Q103, D104
Power Amp.
TA8248K
IC101
Filter (L)
Q104
Filter (R)
Q105
Output
VC VCC DVDD
APO
MD0 ~ MD7
MA0 ~ MA17
DC + 9 V IN
DB4 ~ DB7
COM1 ~ COM16
SEG1 ~ SEG40
RS
R/W
E
KO8 ~
KO12
KI0 ~ KI6
KO0 ~ KO7
ROM(2M-bit)
UM23C2101M
7384/Q
LSI2