Casio WK-1800 Service Manual page 11

DSP and DAC CIRCUIT
The DSP (Digital Signal Processor) and DAC (Digital Analog Converter) consists of the following circuits.
ROM1
LHMN5KPP
LSI1 (32Mbit)
CE,OE A0 ~ A20,NC Q0 ~ Q15
RA23
RA0 ~
RA21
RD0 ~ RD15
RA0 ~ RA21
PG
24.576 MHz
D8 ~
D15
key Control
data data
ROM2
LHMN5KPN
LSI2 (32Mbit)
CE,OE A0 ~ A20,NC Q0 ~ Q15
RA22
RA0 ~
RA21
DSP
HG51B155FD
LSI3
ED0 ~
WE
OE
CS
ED15
D0 ~ D15
Working RAM (256K-bit)
TC55257DFL-70L
LSI4
CPU
HD6433048SA89F
LSI9
— 10 —
SORP: Sound data
BOK: Bit clock
WOK1: Word clock
DAC
BOK
CLK
SI
EA0 ~
EA14
DOUT
A0 ~ A14
SORP
WOK1
WOKI0 DI
Key Controller
D0 ~
TC190C020AF-001
D15
key
data
ROUT
LOUT
LRCK
LRCK0
D0 LRCK0
KC0 ~
KC7
SI0 ~ SI9
LSI16
FI0 ~ FI9
Key-
board