A
B
C
D
E
F
G
H
I
L
M
N
O
P
Q
R
S
T
U
J
K
1
2
3
4
5
6
7
8
9
10
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
7
11
RD-150
Nov, 2000
BLOCK DIAGRAM
MIDI IN
MIDI OUT
DAMPER
L/M
R
OUTPUT
PHONES 1
PHONES 2
R
L
IC1
R
L
IC6
SQLC
RESET
MUTING
SQUELCH
CONTROL
IC2
IC3,Q4,Q5
Q1,Q2,Q3
JACK BOARD
AC INLET
+15V
-15V
A
A
A
A
SWITCHING
POWER SUPPLY
POWER
SWITCH
PHOTO
BUFFER
Q6
IC4
Q7
Q8
CONTROL BOARD
LED+SW
MATRIX
VOLUME
BRILLIANCE
D/A
IC18
T
IC5,IC7
SRAM
4M-FLASH
IC16
DATA
IC11,IC12
A
D
ROUT
WD
MK BK
WA
A
PS RAM
D
WAVE ROM
L
ED
IC17
IC10
XP
OP
A
KEY SCAN
IC14
EA
XRES
MAIN BOARD
LPF
D
D
IP
A
ADDRESS BUS
XRES
D
R
CPU
A
RX
IC9
DATA BUS
IC6
LOUT
A
TX
A
ED
D
KEYBOARD 88 KEYS
+5V
SOFT/EXPR.
Pedal Type
Control
Q9,Q11
Buffer
Buffer
IC7
IC7
OUTPUT
BUFFER
PHONES
BUFFER
REF
REF
1
4
2
5
3
1
4
2
5
3
3
1
2
3
1
2
3
2
1
3
2
1
1
2
3
2
1
3
1
2
