Casio CZ-1 Service Manual And Spare Parts List page 80

Pin
No.
Ttrminal
Nama
In/Out
Function
46
WR
Out Writs signal
output.
Oropt
to
LOW
whan
Main
CPU
writtt
dau
into paripharal dtvicat.
46
ALE
Out
Addrass
latch
tnabla
signal
output.
Dau
signals
00-07
btcoma addrtu
signals
AO—
A7 whan
tha ttrminal
risas
to
HIGH.
47-64 PFO
(A8)
-
PF7
(A1S)
Out
Uppar
addrass signals
(A8
-
A
16).
55-62 PDO
(DO)
-
PD7
(D7)
In/Out Data signals
(DO
-
D7).
63.64
VDD, Vcc
+5V powar
sourca.
7-2. Pin
Functions of
Sub
CPU
Pin
No. Ttrminal
Nama
In/Out Function
1-8
PAO
(LO)
-
PA7
(L7)
Out
LED
driva signals
output.
9
PBO
In
Intarrupt raquast
signal
input
from Masttf Music
LSI.
10
PB1 In Intarrupt raquast signal
input
from
Slavs Music LSI.
11
PB2
Out
Mastar
Musk
LSI chip saiact signal output.
12
PB3
Out
Slavt
Music LSI chip
saltct signal
output.
13 PB4
Out Writa tnabia
signal for
Music
LSIs.
14
PB5 Out ID
(Intarrupt Disabla) signal
output.
Whan
Sub
CPU
is
busy,
it
sands ID
signal
to
Music
LSIs so
as
not to bt
intarruptad.
16
PB6 (LDC)
Out
Stays
HIGH
Itvtl for
approximataly
830
millisaconds aftar
powar
switch
is
turnad
on
in ordar to avoid mil- lighting of
LEDs
and shock
noisa
on powar
UP.
17
PCO (LID Out
LED
driva signal
output.
18 PC1 (SYC) In
Synchronous
signal
from Main CPU.
19 PC2 (CONT) In/Out Control
signal
batwttn Main and Sub CPUs.
20 PC3
(INT2) In Intarrupt
signal
from Music
LSIs.
22-24 PC5
(L8)
-
PC7
(L10)
Out
LED
driva
signals
output.
26 INT1
In Intarrupt signal
from Main CPU.
28
RESET
In Rasat
signal input.
Tha
ttrminal
racaivas a
LOW
Itvtl pulsa at
powar ON.
CPU
intarnal circuits ara
initializad
than.
31 XI
In
1
5MH
z
clock pulsa input.
32 Vsi
Ground
(OV)
sourca.
44
RD
Out
Raad
signal output.
Drops
to
LOW
whan Sub CPU
raads data
from
paripharal dtvicat.
46
WR
Out
Writa
signaJ
output.
Drops to
LOW
whan Sub CPU
writtt
dau
into paripharal davicas.
46
ALE
Out Addrtu
latch anabla signal output.
Dau
signals
D0-D7
btcomt
addrass
signals
AS0-AS7
whtn
tha
urminal
risas to
HIGH.
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