Casio CPS-85 User manual

CPS-85
CPS-85
ELECTRONIC KEYBOARD
POWER VOLUME TRANSPOSE
OFF ON MIN MAX F#GA BC D EAB C
#EF DIGITAL EFFECT TONE MEMORY
PIANO 1
PIANO 2
E. PIANO 1
E. PIANO 2
HARPSI-
CHORD
VIBRA-
PHONE
PIPE
ORGAN
JAZZ
ORGAN
STRINGS
SYNTH-
STRINGS
SELECT SONG A
SONG B RECORD STOP START
CONTROL DEMO
15 10152025

— 1 —
CONTENTS Page
Specifications ............................................................................................................................................ 1
Block Diagram........................................................................................................................................... 3
Circuit Description ..................................................................................................................................... 4
Major Waveforms .................................................................................................................................... 11
Printed Circuit Boards ............................................................................................................................. 12
Schematic Diagrams ............................................................................................................................... 13
Exploded View ....................................................................................................................................... 19
Parts List ................................................................................................................................................. 21
SPECIFICATIONS
GENERAL
Keyboard: 88 full size keys with initial touch response
Polyphony: 24 notes maximum
Tones: 10 (with layering)
Tuning curves: 3 types (preset for each tone)
Digital effects: REVERB
Demo tunes
Number of tunes: 10
Titles: 1. Grande valse brillante
2. Turkish March
3. One-Eighty
4. Opaque Mist
5. Harmonious blacksmith
6. Dream Sequence
7. Fugue in G minor
8. Moveable Blues
9. Rainbow
10. Ave Maria
Playback: Repeat sequential play of all tunes; playback always starts from begin-
ning of tune
Manual memory
Type: Real-time recording and playback
Number of songs: 2 (SONG A, SONG B)
Capacity: Approximately 1,200 notes (SONG A + SONG B)
Back-up: Power supplied by batteries or AC adaptor
Pedal: Damper
Other features Transpose (±1 octave, semitone steps)
Tuning (adjustable, A4 = 440 Hz ±50 cents)
MIDI: 8-channel multi-timbre reception
Speakers: 14 cm ×2 (6 W + 6 W)
Terminals: PHONES (standard stereo jack ×1)
LINE OUT (standard mono jack ×2)
Output impedance: 1.0 KΩ
Output voltage: 1.5 V (RMS) MAX
LINE IN (standard mono jack ×2)
Input impedance: 47 KΩ
Sensitivity: 200 mV
MIDI OUT/IN (DIN jack ×2)

— 2 —
ELECTRICAL
Current drain with 12 V DC:
No sound output 240 mA ±20 %
Maximum volume
with 24 keys from C1 to B2 pressed in Jazz organ tone 2050 mA ±20 %
Volume: maximum, Touch response: maximum
Phone output level (Vrms with 8 Ωload each channel):
with key E3 pressed in Jazz organ tone L-ch 60 mV ±20 %
R-ch 65 mV ±20 %
Speaker output level (Vrms with 4 Ωload each channel):
with key E3 pressed in Jazz organ tone L-ch 860 mV ±20 %
R-ch 920 mV ±20 %
Lineout output level (Vrms with 47 kΩload each channel):
with key B5 pressed in Jazz organ tone L-ch 140 mV ±20%
R-ch 160 mV ±20%
Minimum operating voltage: 6.5 V
DAMPER PEDAL (standard mono jack ×1)
DC 12 V (DC jack ×1)
Power supply Dual power supply system
Batteries: 6 D-size batteries
Battery life: Approximately 4 hours on manganese batteries
AC adaptor: AD-12
Auto power off: Turns power off approximately 5 minutes after last key operation.
Enabled under battery power only, can be disabled manually.
Power consumption: 18 W
Dimensions (HWD): 100 ×1372 ×414 mm (without stand)
(3-15/16 ×54-1/16 ×16-5/16 inches)
Weight: Without stand and excluding batteries 16.8 kg (37.1 lbs)

— 3 —
BLOCK DIAGRAM
Buttons
Keyboard
FI0 ~ FI10
SI0 ~ SI10
KC0 ~ KC7
KI0 ~ KI2
MIDI
INOUT
Working Storage
RAM (64K-bit)
LSI2
HY6264ALLJ-70
MA0
~
MA12
MD0
~
MD7
MD0 ~ MD15
MA1 ~ MA19
Sound Source ROM
(8M-bit)
LSI3
MX23C1610MC-12
CPU
LSI4
GT913F
BCK, SO, LRCKMA0, MA1
EA0 ~
EIO0 ~
EA14
EIO7
Effect RAM
(256K-bit)
LSI5
TC55257DFL-70L
DSP
LSI1
HG51B277FB
LEDs
VDD
SONGA
SONGB
DIGITAL EFFECT
SELECT
STOP
LRCK SO
Rmel Lmel
BCK
D/A Converter
LSI6
UPD6379GR
Filter
IC104
Main
Volume
Power Amplifier
IC101
LA4620
Output
Speakers
Reset IC
IC 1
RN5VD35AA
Pre. Amp.
IC103 Line In
POWER (APO) Power Supply Circuit
Q101 ~ Q106
D108, D110, D111
6 ×D-size batteries
AC adaptor AD-12
From CPU
Line Out
AVCCVDD VCC AVDD LVDD

— 4 —
CIRCUIT DESCRIPTION
KEY MATRIX
Note: Each key has two contacts,
the first conatct (1) and second contact (2).
Key
Second contact (2) First contact (1) KC
SI
FI
0CK1CK2CK3CK4CK5CK6CK7CK
0IF)1(0A)1(0#A)1(0B)1(1C)1(1#C)1(1D)1(1#D)1(1E
0IS)2(0A)2(0#A)2(0B)2(1C)2(1#C)2(1D)2(1#D)2(1E
1IF)1(1F)1(1#F)1(1G)1(1#G)1(1A)1(1#A)1(1B)1(2C
1IS)2(1F)2(1#F)2(1G)2(1#G)2(1A)2(1#A)2(1B)2(2C
2IF)1(2#C)1(2D)1(2#D)1(2E)1(2F)1(2#F)1(2G)1(2#G
2IS)2(2#C)2(2D)2(2#D)2(2E)2(2F)2(2#F)2(2G)2(2#G
3IF)1(2A)1(2#A)1(2B)1(3C)1(3#C)1(3D)1(3#D)1(3E
3IS)2(2A)2(2#A)2(2B)2(3C)2(3#C)2(3D)2(3#D)2(3E
4IF)1(3F)1(3#F)1(3G)1(3#G)1(3A)1(3#A)1(3B)1(4C
4IS)2(3F)2(3#F)2(3G)2(3#G)2(3A)2(3#A)2(3B)2(4C
5IF)1(4#C)1(4D)1(4#D)1(4E)1(4F)1(4#F)1(4G)1(4#G
5IS)2(4#C)2(4D)2(4#D)2(4E)2(4F)2(4#F)2(4G)2(4#G
6IF)1(4A)1(4#A)1(4B)1(5C)1(5#C)1(5D)1(5#D)1(5E
6IS)2(4A)2(4#A)2(4B)2(5C)2(5#C)2(5D)2(5#D)2(5E
7IF)1(5F)1(5#F)1(5G)1(5#G)1(5A)1(5#A)1(5B)1(6C
7IS)2(5F)2(5#F)2(5G)2(5#G)2(5A)2(5#A)2(5B)2(6C
8IF)1(6#C)1(6D)1(6#D)1(6E)1(6F)1(6#F)1(6G)1(6#G
8IS)2(6#C)2(6D)2(6#D)2(6E)2(6F)2(6#F)2(6G)2(6#G
9IF)1(6A)1(6#A)1(6B)1(7C)1(7#C)1(7D)1(7#D)1(7E
9IS)2(6A)2(6#A)2(6B)2(7C)2(7#C)2(7D)2(7#D)2(7E
01IF)1(7F)1(7#F)1(7G)1(7#G)1(7A)1(7#A)1(7B)1(8C
01IS)2(7F)2(7#F)2(7G)2(7#G)2(7A)2(7#A)2(7B)2(8C
0IK
LATIGID
TCEFFE /1ONAIP 2ONAIP /1ONAIP.E 2ONAIP.E
-CISPRAH
/DROH
-HPARBIV
ENO
EPIP
/NAGRO
ZZAJ
NAGRO
/SGNIRTS
HTNYS
SGNIRTS TCELES /AGNOS
BGNOS
1IKDROCERLORTNOCOMED -OPSNART
#FES -OPSNART #GES -OPSNART #AES -OPSNART DES -OPSNART EES
2IKPOTSTRATS -OPSNART
GES -OPSNART AES -OPSNART BES -OPSNART #CES

— 5 —
NOMENCLATURE OF KEYS
POWER SUPPLY CIRCUIT
The power supply circuit generates five voltages as shown in the following table. VDD voltage is always
generated. The others are controlled by POWER signal from the CPU.
RESET CIRCUIT
When batteries are set or an AC adapter is connected, the reset IC provides a low pulse to the CPU. The
CPU then initializes its internal circuit, and clears the working storage RAM.
When the power switch is pressed, the CPU receives a low level signal. The CPU sends POWER signal
to the power supply circuit, also sends a reset signal to the DSP.
When the keyboard is powered by batteries and no operation is made for six minutes, CPU drops signal
POWER to shut all the voltage except VDD off.
C2
C#2 D#2 F#2 G#2A#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 C#6 D#6 F#6 G#6 A#6 C#7 D#7 F#7 G#7 A#7
D2 E2 F2 G2 A2 B2C1 D1 E1 F1 G1 A1 B1A0 B0 C3 D3 E3 F3 G3 A3 B3
C#1 D#1 F#1G#1A#1
A#0
C4 D4 E4 F4 G4 A4 B4 C5 D5 E5 F5 G5 A5 B5 D6 E6 F6 G6 A6 B6C6 C7 D7 E7 F7 G7 A7 B7 C8
Reset IC
IC1
RN5VD35AA
DSP
LSI1
HG51B277FB
VDD
Reset signal
To power supply circuit
VDD Battery set
RESET
VDD
Power switch NMI
POWER
PLE
CPU
LSI4
GT913F
SCKO
emaNegatloVfonoitareporoF
DDVV5+ MARtceffE,MARegarotsgnikroW,MORecruosdnuoS,PSD,CIteseR,UPC
DDVAV5+skcajnieniL,CAD
DDVLV5+pmaltoliP
CCVV9+reifilpmarewoP,skcajtuoeniL
CCVAV9+.pmAerP

— 6 —
CPU (LSI4: GT913F)
The 16-bit CPU contains a 1k-byte RAM, three 8-bit I/O ports, two timers, a key controller and serial interfaces.
The CPU detects key velocity by counting the time between first-key input signal FI and second-key SI from
the keyboard. The CPU reads sound data and velocity data from the sound source ROM in accordance with
the selected tone; the CPU can read rhythm data simultaneously when a rhythm pattern is selected. Then the
CPU provides 16-bit serial sound data to the DSP. The CPU also controls MIDI input/output and stores
sequencer data into the working storage RAM.
The following table shows the pin functions of LSI4.
.oNniPlanimreTtuO/nInoitcnuF
10DXTtuOtuptuolangisIDIM
20DXRnItupnilangisIDIM
30KCStuOtuptuolangis)FFOrewoPotuA;OPA(REWOP
41DXT— .dnuorgotdetcennoC.desutoN
51DXRnItupnilangisNOrewoP
61KCStuOtuptuoeslupgnizinorhcnysZHM1
9~7
,0NA,CCVA
1NA
—.dnuorgotdetcennoC.desutoN
01DNGAnIecruos)V0(dnuorG
11KCBtuOtuptuokcolctiB
21OStuOtuptuoataddnuoslaireS
31KCRLtuOtuptuokcolcdroW
41DNGnIecruos)V0(dnuorG
61,511TLX,0TLXtuO/nItuptuo/tupnikcolczHM42
71CCVnIecruosV5+
91,811DOM,0DOMnI.dnuorgotdetcennoC.lanimretnoitcelesedoM
02BTSRnItupnilangisteseR
12IMNnItupnilangisNOrewoP
22TNI— dnuorgotdetcennoC
03~32 3IF~0IF
3IS~0IS nIlangistupniyekroflanimreT
83~137CK~0CKtuOlangisnacsyekroflanimreT
25~93
01IF~4IF
01IS~4IS
nIlangistupniyekroflanimreT
55~352IK~0IKnIlangistupninottubroflanimreT
65BNWMtuOPSDehtroflangiselbaneetirW
67~7591AM~0AMtuOsubsserddA
770BSCMtuOMORecruosdnuosehtroftuptuolangiselbanepihC
871BSCMtuOdesutoN
972BSCMtuOPSDehtroftuptuolangiselbanepihC
08CCVnIecruosV5+
18DNGnIecruos)V0(dnuorG
28BDRMtuOMORecruosdnuosehtroftuptuolangiselbanedaeR
89~3851DM~0DMtuO/nIsubataD
99ELPnI lanimreteht,rotpadaCAnaybderewopsidraobyekehtnehW langisfforewopotuadnestonseodUPCehttahtostlov0semoceb .tiucricylppusrewopehtot
00171PnItupniladeP

— 7 —
DIGITAL SIGNAL PROCESSOR (LSI1: HG51B227FB)
The DSP receives 16-bit serial sound data from the CPU and adds the selected effect to the sound data using
the effect RAM. Then the DSP provides the sound data to the DAC. The DSP also drives LEDs.
The following table shows the pin functions of LSI1.
.oNniPlanimreTtuO/nI noitcnuF
08,4~14BP~0BP— .dnuorgotdetcennoC.desutoN
5OStuOCADehtroftuptuoataddnuoslaireS
6OKCWtuOCADehtroftuptuokcolcdroW
73DDVnIecruosV5+
8TSET—desutoN
9BSERnItupnilangisteseR
012SSVnIecruos)V0(dnuorG
21,11TUOX,NIXtuO/nItuptuo/tupnikcolczHM61
31IKCWnIUPCehtmorftupnikcolcdroW
41ISnIUPCehtmorftupniataddnuoslaireS
51IKCBnIUPCehtmorftupnikcolctiB
61CNISnItupnieslupgnizinorhcnyszHM1
712DDVnIecruosV5+
52~817OI~0OItuO/nIsubataD
62BECRtuOMARegarotsgnikrowehtroftuptuolangiselbanepihC
723SSVnIecruos)V0(dnuorG
821DAnIsubsserddA
92BEO— .dnuorgotdetcennoC.desutoN
03BEWnIlangiselbaneetirW
133DDVnIecruosV5+
232ECnI.evitcahgiH.tupnilangiselbanepihC
330DAnIsubsserddA
43B1ECnI.evitcawoL.tupnilangiselbanepihC
34,14~537OIE~0OIEtuO/nIMARtceffeehtrofsubataD
,84~64,44,24
16,95~15
41AE~0AEtuOMARtceffeehtrofsubsserddA
54BECEtuOMARtceffeehtroftuptuolangiselbanepihC
94BEOEtuOMARtceffeehtroftuptuolangiselbanedaeR
053SSVnIecruos)V0(dnuorG
06BEWEtuOMARtceffeehtroftuptuolangiselbaneetirW
87,47,07,66,262SSVnIecruosdnuorG
97,57,17,76,362DDVnIecruosV5+
,96,86,56,46
37,27 5AP~0APtuOtuptuolangisnacsnottuB
77,677/6APtuOdesutoN

— 8 —
FILTER BLOCK
Since the sound signals from the DAC are stepped waveforms, the filter block is added to smooth the
waveforms.
DAC (IC1: UPD6379GR)
The DAC receives 16-bit serial data output from the DSP. The data contains digital sound data of the
melody, chord, bass, and percussion for the right and left channels. The DAC converts the data into
analog waveforms and output them to each channel separately.
Synch signal
Data
Word clock
Bit clock
Data
Word clock
Bit clock
DSP
LSI1
HG51B277FB
DAC
LSI6
UPD6379GR
CPU
LSI4
GT913F
L OUT
R OUT
SI
LRCK
CLK
SO
WCKO
SCK1
SO
LRCK
BCK
SINC
SI
WCKI
BCKI
AVCC
Left
L
Right
From DAC
From DAC
To main volume
To main volume R
AVCC
10 µF
10 µF
15 V10 µ
15 V10 µ
10 K
C472(H)
C472(H)
100 K
2.7 K
R154
100 K
C152(H)
C221B(A)
C152(H)
C221B(A)
2.2 K
10 K10 K
10 K10 K10 K
AGAG
M5218APR
(1/2) ×2
IC104
AG
AG
AG
AG
2
2
+
–
+
–
12
3
45
6
78

— 9 —
POWER AMPLIFIER (IC101 : LA4620)
The power amplifier is a two-channel amplifier with standby switch.
6
16 2 10 11 13
12
Pre-drive
Amp.
Input
Amp. Power Amp.
+
–
Pre-drive
Amp.
Input
Amp. Power Amp.
+
–
9
7
3
5
+
–
Input
Amp. Pre-drive Amp. Power Amp.
+
–
Input
Amp. Pre-drive Amp. Power Amp.
4
19
20
21
22
23
1
18
17
15
14
8
RL Short
Protector
RL Short
Protector
Terminal
Protection
Circuit
Pop Noise
Prevention
Circuit
Ripple
Filter
IN11+
IN11–
IN12–
IN21+
IN21–
IN22–
NC DC MUTE ADJ
Boot11
OUT11
PoGND1
OUT12
Boot12
VCC1
Boot21
OUT21
PoGND2
OUT22
Boot22
VCC2
PriGND