CTK-401
100 SONG BANK (00-49)
100 RHYTHMS
ON
OFF
POWER/MODE
FINGERED
CASIO
CHORD
NORMAL
MAIN
SYNCHRO/
START/
VOLUME
FILL-IN
STOP TEMPO
CHORD BOOK
ACCOMP VOLUME
TONE
RHYTHM
SONG BANK
STATUS
TEMPO
VOLUME
m 7 M7 dim
M
01234
5
6789
aug sus4 -5 add9 CLEAR
ELECTRONIC KEYBOARD
MUSICAL INFORMATION SYSTEM
TONE SONG BANK
RHYTHM
TRANSPOSE/
TUNE
REW STOP FF
LEFT
ON/OFF
100 TONES
100 SONG BANK (50-99)
RIGHT
ON/OFF
PLAY/
S
PAUSE
O
R
N
E
G
L
L
B
O
A
R
N
T
K
N
C
O
100 SONG BANK KEYBOARD
MUSICAL INFORMATION SYSTEM
SONG BANK CONTROLLER
CTK-401
CONTENTS
Specifications................................................................................................................................... 1
Block Diagram.................................................................................................................................. 2
Circuit Description............................................................................................................................ 3
Adjustment ....................................................................................................................................... 7
Major Waveforms ............................................................................................................................. 8
Printed Circuit Boards ...................................................................................................................... 9
Schematic Diagrams ...................................................................................................................... 11
Exploded View ............................................................................................................................... 15
Parts List ........................................................................................................................................ 17
SPECIFICATIONS
GENERAL
Keyboard: 49 standard-size keys, 4 octaves
Tones: 100
Polyphony: 12 notes maximum (6 for certain tones)
Auto accompaniment
Rhythm patterns: 100
Tempo: Variable (236 steps, = 20 to 255)
Chords: 2 fingering methods (CASIO CHORD, FINGERED)
Rhythm controller: START/STOP, SYNCHRO/FILL-IN
Accomp volume: 0 to 9 (10 steps)
Song bank
Tunes: 100
Controllers: PLAY/PAUSE, STOP, REW, FF, LEFT ON/OFF, RIGHT ON/OFF
Musical dictionary
Name display: TONE, RHYTHM, SONG BANK name/number
Tempo: Tempo value, metronome, synchro standby, beat indicator
Chord: Chord name, Chord form
Fingering: Fingering indcators, parts
Song bank status: PLAY, PAUSE, REW, FF, playing
Staff: Four octaves with sharp and flat indications
Keyboard: Four octaves
Other functions
Transpose: 12 steps (–6 semitones to +5 semitones)
Tuning: Variable (A4 = approximately 440 Hz ± 50 cents)
Volume: 0 to 9 (10 steps)
Terminals
Phones/Output terminal: Stereo standard jack
Output Impedance: 100 Ω
Output Voltage: 3.0 V (RMS) MAX
Power supply terminal: 9 V DC
Power supply Dual power supply system
Batteries: Six AA-size batteries
Battery life: Approximately 2 hours (SUM-3/R6P)/6 hours (AM3/LR6)
AC adaptor: AD-5
Auto power off: Turns power off approximately six minutes after last key operation. Enabled
under battery power only, can be disabled manually.
Speaker output: 2.0 W + 2.0 W
Power consumption: 9 V --- 7.0 W
Dimensions (HWD): 988 × 332 × 124 mm (38-15/16 × 13-1/16 × 4-7/8 inches)
Weight: Approximately 3.5 kg (7.7 lbs) (without batteries)
ELECTRICAL
Current drain with 9 V DC:
No sound output 100 mA ± 20 %
Maximum volume 625 mA ± 20 %
with 12 keys C4 to B4 pressed in Synth-Lead 1
Volume: 9 (Max.)
Phone output level (Vrms with 8 Ω load each channel):
with key A4 pressed in Synth-Lead 1 67 mV ± 20 %
Speaker output level (Vrms with 4 Ω load each channel):
with key A4 pressed in Synth-Lead 1 900 mV ± 20 %
Minimum operating voltage: 5.7 V
— 1 —
CIRCUIT DESCRIPTION
KEY MATRIX
KI0 KI1 KI2 KI3 KI4 KI5 KI6
KO0 C2 G#2 E3 C4 G#4 E5 C6
KO1 C#2 A2 F3 C#4 A4 F5
KO2 D2 A#2 F#3 D4 A#4 F#5
KO3 D#2 B2 G3 D#4 B4 G5
KO4 E2 C3 G#3 E4 C5 G#5
KO5 F2 C#3 A3 F4 C#5 A5
KO6 F#2 D3 A#3 F#4 D5 A#5
KO7 G2 D#3 B3 G4 D#5 B5
KO8 —+ 0
KO9 321
KO10 654
Tempo
Down
Start/
Stop
Transpose/
Tune
KO11 9 8 7 Fingered
KO12 FF Right
Play/
Pause
Stop Left Rewind
Tempo
Up
Synchro/
Fill-in
Song
Bank
CASIO
Chord
Volume
Down
Chord
Book
Rhythm Tone
Normal Power Off
NOMENCLATURE OF KEYS
C#2 D#2 F#2 G#2 A#2 C#3 D#3 F#3 G#3 A#3 C#4 D#4 F#4 G#4 A#4 C#5 D#5 F#5 G#5 A#5
C2
D2 E2 F2 G2 A2 B2 C3 D3 E3 F3 G3 A3 B3 C4 D4 E4 F4 G4 A4 B4 C5 D5 E5 F5 G5 A5 B5 C6
Volume
Up
Accomp
Volume
— 3 —
CPU (LSI1: MSM6755B-17)
The CPU reads sound data from the ROM in accordance with the pressed key and the selected tone; the CPU
can read rhythm data simultaneously when a rhythm pattern is selected. Then it provides the left and the right
channels’ waveforms separately, by converting the data into the waveforms with two built-in DACs. The CPU
also controls key and button input. The following table shows the pin functions of LSI1.
Pin No. Terminal In/Out Function
1 MA14 Out Address bus
2, 3 NCO — Not used
4 ~ 19 MA0 ~ MA13 Out Address bus
13 MRDB Out Read enable signal
17 MCSB — Not used
20 ~ 27 MD0 ~ MD7 In/Out Data bus
28, 29 NC1, NC2 — Not used
30 DGND In Ground (0 V) source
31 DVCC In +5 V source
32, 33 XTLO, XTLI In/Out 20 MHz clock input/output
34 NC3 — Not used
35 RSTB In Reset signal input
36 P24/RXD — Not used. Connected to +5 V.
37 P25/TXD — Not used
38 NMI In Power ON signal input. Connected to +5 V.
39 APO Out APO (Auto Power Off) signal output
40 NC4 — Not used
41 REFH Out Terminal for the internal DAC
42, 43 NC5, NC6 — Not used
44 DAOR Out Right channel sound waveform output
45 NC7 — Not used
46 AVdac In +5 V source for the internal DAC
47 DAOL Out Left channel sound waveform output
48 REFL Out Terminal for the internal DAC and ADC
49 AGdac In Ground source for internal DAC
50 AGadc In Ground source for internal ADC
51 ANI In APO cancellation signal
52 AVadc In +5 V source for the internal ADC
53 NC8 — Not used
54 MOD0 In Mode selection terminal. Connected to +5 V.
55, 56 MOD1, MOD2 In Mode selection terminal. Connected to ground.
57 P40 — Not used
58 ~ 64 KI0/P30 ~ KI7/P36 In Terminals for key/button input signal
65 KI7/P37 — Not used
66 ~ 73 KO0/P50 ~ KO7/P57 Out Terminals for key scan signal
— 4 —