Casio CTK-573 Service Manual page 8

Pin No. Terminal
57 ~ 76 MA0 ~ MA19
77, 78 MCSB0, MCSB1
79 MCSB2
80 VCC
81 GND
82 MRDB
83 ~ 98 MD0 ~ MD15
99 PLE
100 P17
LCD DRIVER (LSI401: ML9040-B02GA)
The LCD driver can drive a dot matrix LCD having 40 segment and 16 common lines. The LSI contains 160
characters in the built-in character generator ROM, and stores 8 characters in the built-in display data RAM.
In accordance with command from the CPU, the LSI is capable of displaying up to 8 characters simultaneously.
The following table shows the pin functions of LSI 401.
Pin No. Terminal
1 ~ 22,
SEG1 - SEG4O
63 80
23 GND
24, 25 OSC1, OSC2
26 ~ 30 V1 ~ V5
31, 32 L, CP
33 VDD
34, 35 DF, DO
36 RS
37 R/W
38
39 ~ 42 DB0 ~ DB3
43 ~ 46 DB4 ~ DB7
47 ~ 53, COM1 ~ COM7
55 ~ 62 COM9 ~ COM16
54 COM8
In/Out
Out Address bus
Chip enable signal output for the sound source ROM and
Out
working RAM
Out Not used
In +5 V source
In Ground (0 V) source
Out
Read enable signal output for the sound source ROM
In/Out Data bus
Out Terminal for pedal signal
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 (+5.3 V) source
— Not used
Data/command determination terminal.
In
High: data, Low: command
In Read/write terminal. High: read, Low: write
Chip enable signal.
E In High: enable, the writing is done at fall edge.
Low: disenable
— Not used. Connected to GND (0 V)
In/Out Data bus
Common signal/output
Out
— Not used
Function
Function
— 7 —