Casio Celviano AP-21 User manual

ELECTRONIC KEYBOARD
AP-21
MAY 1999
AP-21

— 1 —
CONTENTS
Safety Notice...................................................................................... 1
Specifications .................................................................................... 2
Block Diagram ................................................................................... 3
PCB Layout ........................................................................................ 4
Disassembly Instructions ................................................................. 5
Circuit Description ............................................................................ 8
Major Waveforms............................................................................. 10
Troubleshooting .............................................................................. 11
Wiring Diagram ................................................................................ 14
Exploded View ................................................................................. 15
Parts List .......................................................................................... 16
Schematic Diagrams ....................................................................... 19
SAFETY NOTICE
CAUTION!
Danger of explosion if battery is incorrectly replaced.
Replace only with the same of equivalent type recommended
by the appliance manufacturer.Discard used batteries
according to manufacturer's instructions.

— 2 —
SPECIFICATIONS
GENERAL
Number of keys: 88
Polyphonic: 32-note
Preset tones: Piano-1, Piano-2, Electric Piano, Harpsichord, Vibraphone, Pipe Organ, Strings,
Choir.
Keyboard Controls: Touch sensitivity (Initial touch: Light/Middle/Heavy),
Tuning curve (Standard/Electric piano/Flat),
Baroque pitch (On/Off)
Pedals: Soft/Sostenuto, Damper
Effects: Reverb (Room, Stage, Hall-1, Hall-2), Chorus, Tremolo, Brilliance
Transpose: F# - C - F
Tuning control: A4 = 440Hz ±50 cents
Demonstration tunes: 1: Polonais "Héroïque" (F.F. Chopin) 5: CASIO original
2: Frühlingslied Op. 62-6 (F. Mendelssohn) 6: jesus, Bleibet Meine Freude (J.S. Bach)
3: CASIO original 7: CASIO original
4: Harmonious blacksmith (G.F. Händel) 8: CASIO original
Memory: Real-time recording [Number of Songs: (A and B), Capacity: Approx. 3,000
notes total]
Backup Battery [Built-in lithium battery: BR2330, Battery life: Approx. 5years]
Terminals: LINE IN Jack [Input impedance: 30KΩ, Sensitivity: 200mV]
LINE OUT Jack [Out put impedance: 22KΩ, Output voltage: 2.0V (rms) MAX],
Phone Jack [6.3ø, stereo], MIDI jack (IN, OUT, THOUGH)
Speakers: 16cm dia. Approx. 20W input Rating: 2 pcs.
Power source: AC source (120V, 230/240V)
Power consumption: 48W (120V AC), 62W (230/240V AC)
Dimensions: 7-3/4" (H) ×54 (W) ×18 - 1/2" (D)
198mm (H) ×1370mm (W) ×470mm (D)
Weight: 36.4kg (80.3 lbs) /45.5kg (100.3 lbs) with stand
C2# D2# C6# D6# G6#F6# A6# C7# D7#
D2 G7
G1#
A0 B0 A2F1 F2G1 G2A1 B1 B2C1 D1 C6E1 E2 G6E6 F6 A6 B6 C7D6 E7 F7D7C2 C8B7A7
A1# A2#G2#F1# F2#D1#C1#AD# A7#G7#F7#
Nomenclature of keys

— 3 —
BLOCK DIAGRAM
Keyboard Pedal
unit
FI0~FI10
SI0~SI10
L1~L18
KI0
KI3
KC0~
KC7
Mute signal
D0~D7
SOLP
SORP
Reset signal
VDD (+5V)
AVDD (+5V)
AVCC (+15V)
AVFF (-15V)
Mute signal
IC 408
IC 411 Main
volume
BOK, WOK1
SOLM
SOLM
RD0~RD15
RA0~RA22
ED0~
ED15 EA0~ EA14
A0~A14
A0~A16
MIDI
OUT IN THROUGH
Damper SS SF
P10, P12~P16,
P93, P94, P97
P70~P77
P12~P14
BRILLIANCE
Key touch LSI
LSI 10
HG52E35P CPU
LSI 1
HD6435328RC13F
LSI-S
LSI 7
HG51B155FD-1
LSI4,5
UPD6376GS-E1
DAC
DAC
LPF
LPF
MIXER
IC 406
Reset IC
IC 5
Power supply
circuit
Power
amp.
IC 405
Sound Source Rom
(3M-bit)
LSI 6
MX23C2410MC-12CA58
System ROM
LSI 2
2M-bit
LH532KU3
Effector RAM
256K-bit
LSI 8, 9
TC55257DFL-70L
Working strage
LSI 3
SRAM 256K-bit
TC55257DFL-70L
LEDS
Console
Gate array
LSI 301
UPD65005GF
-419
~
KC0
KC4
~

— 4 —
PCB LAYOUT
PCB
Main PCB
Sub PCB
Console PCB
Other PCBs
JCM358-
MA1M
PS2M
CN1M
CN2M
PS12
PS3M
PS4M
Components
CPU, LSI-S, Sound Source ROM Working storage
RAM, Effect RAM Reset IC, DAC, Key Controller
Filter, Lineout Amp., Power Amp. Power supply cir-
cuit. MIDI input/output.
LEDs, Buttons, Gate array
Main Volume
Fuse
Head phone Jack
Power lamp
POWER
VOLUME
MIN MAX
TRANSPOSE/
TUNE/MIDI DIGITAL EFFECT CHORUS REVERB
REVERB2
REVERB1
TONE
PIANO E.PIANO HARPSI-
CHORD PIPE ORGAN STRINGS
SONG A
SONG B RECORD
START/
STOP
DEMO
MEMORY
OFF
ON
AP-21
MA1M
PS2M
PS12
PS3M
PS4M
CN1MCN2M
KY1M KY2M KY3M

— 5 —
DISASSEMBLY INSTRUCTIONS
1. Removal of top board
1-1. Remove 6 screws affixing the top board on the back.
1-2. Slide the top board forward and remove it from the main
unit.
2. Removal of keyboard cover
2-1. Lift up the keyboard cover full open position.
2-2. Unscrew the L-shaped stopper metal located on the inner
left corner.
2-3. Lift up the keyboard cover gear from the opening where
stopper metal is fixed then remove the keyboard cover.

— 6 —
5. Removal of keyboard unit
5-1. Disconnect connector CA on the PCB MA1M.
5-2. Remove 23 screws that affix the keyboard unit
(16 on the bottom of the case and 7 on the
keyboard unit).
5-3. Lift and remove the keyboard unit.
4. Removal of front cover
4-1. Remove 6 screws from the front end of the lower case.
4-2. Lift the front cover and remove the pilot lamp that is affixed
by 2 screws. Then remove the front cover.
3. Removal of console panel
3-1. Remove screws affixing both ends of the console panel.
3-2. Disconnect connector CD on PCB MA1M, connector CF on PCB PS2M, and transformer grounding
wire.
3-3. Lift the console panel and turn it over and remove the power switch, which is affixed by 2 screws.
Then remove the side panel.
Caution: Be careful not to scratch the side panels.
Earth cable Screw Connector (CD) Connector (CD)
screws
Keyboard screws
Front cover screws
Bottom
Keyboard screws

— 7 —
6. Removal of keys
6-1. While plying the side partition plastics with tweezers, lift
the edge of the key toward front.
7. Removal of keyboard PCB
7-1. Lay the keyboard so that keyboard PCBs face upward.
7-2. Remove screws on keyboard PCBs (10 screws on PCBs
KY1M and KY3M, 12 screws on KY2M).
7-3. Unsolder the cable.
8. Totes on replacing the main PCB.
A lithium battery is set on the main PCB for memory protection.
When you replace the main PCB, disconnect the jumper to open battery circuit.
Since there is no jumper on a new main PCB, be sure to set a jumper.
jumper

— 8 —
CIRCUIT DESCRIPTION
KEYMATRIX
KC0 KC1 KC2 KC3 KC4 KC5 KC6 KC7
FI0 A0 1 A0 # 1 B0 1 C1 1 C1 # 1 D1 1 D1 # 1 E1 1
SI0 A0 2 A0 # 2 B0 2 C1 2 C1 # 2 D1 2 D1 # 2 E1 2
EI1 F1 1 F1 # 1 G1 1 G1 # 1 A1 1 A1 # 1 B1 1 C2 1
SI1 F1 2 F1 # 2 G1 2 G1 # 2 A1 2 A1 # 2 B1 2 C2 2
FI2 C2 # 1 D2 1 D2 # 1 E2 1 F2 1 F2 # 1 G2 1 G2 # 1
SI2 C2 # 2 D2 2 D2 # 2 E2 2 F2 2 F2 # 2 G2 2 G2 # 2
FI3 A2 1 A2 # 1 B2 1 C3 1 C3 # 1 D3 1 D3 # 1 E3 1
SI3 A2 2 A2 # 2 B2 2 C3 2 C3 # 2 D3 2 D3 # 2 E3 2
FI4 F3 1 F3 # 1 G3 1 G3 # 1 A3 1 A3 # 1 B3 1 C4 1
SI4 F3 2 F3 # 2 G3 2 G3 # 2 A3 2 A3 # 2 B3 2 C4 2
FI5 C4 # 1 D4 1 D4 # 1 E4 1 F4 1 F4 # 1 G4 1 G4 # 1
SI5 C4 # 2 D4 2 D4 # 2 E4 2 F4 2 F4 # 2 G4 2 G4 # 2
FI6 A4 1 A4 # 1 B4 1 C5 1 C5 # 1 D5 1 D5 # 1 E5 1
SI6 A4 2 A4 # 2 B4 2 C5 2 C5 # 2 D5 2 D5 # 2 E5 2
FI7 F5 1 F5 # 1 G5 1 G5 # 1 A5 1 A5 # 1 B5 1 C6 1
SI7 F5 2 F5 # 2 G5 2 G5 # 2 A5 2 A5 # 2 B5 2 C6 2
FI8 C6 # 1 D6 1 D6 # 1 E6 1 F6 1 F6 # 1 G6 1 G6 # 1
SI8 C6 # 2 D6 2 D6 # 2 E6 2 F6 2 F6 # 2 G6 2 G6 # 2
FI9 A6 1 A6 # 1 B6 1 C7 1 C7 # 1 D7 1 D7 # 1 E7 1
SI9 A6 2 A6 # 2 B6 2 C7 2 C7 # 2 D7 2 D7 # 2 E7 2
FI10 F7 1 F7 # 1 G7 1 G7 # 1 A7 1 A7 # 1 B7 1 C8 1
SI10 F7 2 F7 # 2 G7 2 G7 # 2 A7 2 A7 # 2 B7 2 C8 2
FI
KC
SI
LSI
HG52E35P
Second contact First contact
1
2

— 9 —
POWER SUPPLY CIRCUIT
The power supply circuit generates five voltages as shown in the following table.
Name Voltage For operation of
VDD +5 V CPU, Reset IC, DSP, Sound source ROM, Working storage RAM, Effect RAM,
Key touch LSI, Gute array, LEDs
AVDD +5 V DAC
AVCC +15 V Filter, Mixer
AVFF -15 V Filter, Mixer