Casio CTK-541 Service Manual page 8

Pin No. Terminal
80 VCC
81 GND
82 MRDB
83 ~ 98 MD0 ~ MD15
99 PLE
100 P17
LCD DRIVER (LSI3: KS0066U-10B)
The LCD driver can drive a dot matrix LCD having 40 segment and 16 common lines. The LSI contains 240
graphic symbols in the built-in character generator ROM, and stores 80 characters in the built-in display data
RAM. In accordance with command from the CPU, the LSI is capable of displaying up to 16 characters
simultaneously. The following table shows the pin functions of KS0066U-10B.
Pin No. Terminal
1 ~ 22,
SEG1 ~ SEG40
63 ~ 80
23 VSS
24, 25 OSC1, OSC2
26 ~ 30 V1 ~ V5
31, 32 LP, XCLS
33 VDD
34, 35 FR, DO
36 RS
37 R/W
38 E
39 ~ 42 DB0 ~ DB3
43 ~ 46 DB4 ~ DB7
47 ~ 62 COM1 ~ COM16
In/Out
In +5 V source
In Ground (0 V) source
Out Read enable signal output for the sound source ROM
In/Out Data bus
Out Reset signal output for the DSP
In/Out Data bus for the LCD driver
In/Out
Out Segment signal output
— GND (0 V) source
Terminals for the built-in clock pulse generator. The external
In/Out
resistor connected determines the oscillation frequency.
LCD drive voltage input.
In Those voltages are used for generating the stepped pulse of
the LCD drive signals.
— Not used
In DVDD (+5 V) source
— Not used
Data/command determination terminal.
In
High: data, Low: command
In Read/Write terminal. High: read, Low: write
Chip enable signal.
In High: enable, the writing is done at fall edge.
Low: disenable
— Not used. Connected to GND (0 V)
In/Out Data bus
Out Common signal/output
— 6 —
Function
Function