Casio CTK-650 User Manual

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CIRCUIT DESCRIPTION
CPU(HD6433298A16P : H8/329)
The 16-bit CPU contains a 32K-byte ROM, a 1K-byte RAM, an 8-bit A/D converter, timers and I/O ports.  The
CPU accesses to the DSP, Key Touch LSI, RAM, buttons and LEDs. But the CPU directly receives MIDI and
pedal signals.
Pin No.
Terminal
In/Out
Function
1
P40/IRQ2
In
KO signal data.
2
P41/IRQ1
In
Timing signal for KO signal.
3
P42/IRQ0
In
APO signal output.
4
P43/-RD
Out
Read signal outpt.
5
P44/-WR
Out
Write signal output.
7
P46/PHI
Out
System clock output.
8
P47/-WAIT
In
Wait signal input
9
P50/Txd
Out
MIDI signal output.
10
P51/Rxd
In
MII signal input.
11
P52/SCK
Out
Reset signal output.
12
-RESET
In
Reset signal input.
13
-NMI
In
Power on signal input.(Low active)
14
Vcc
In
+5V source.
15
-STBY
In
Standby signal input. Connected to +5V.
16
Vss
In
Ground(0V) source.
17,18
XTAL,EXTAL
In/Out 20MHz clock pulse input/output. Connected to crystal.
19,20
MD1,MD0
In
Selection for system.
MD1 MD0
MODE
0
1
MODE-1 : Internal ROM mode
1
0
MODE-2 : Non internal ROM mode
1
1
MODE-3 : Single chip mode
21
AVss
In
Analog ground source.
22
P70/AN0
In
Connected to ground.
23~29
P71/AN0~P77/AN7
In
KI signal input.
30
AVcc
In
+5V source.
31~38 P60/FTCI~P67/TMO1
Out
Control signal for 7-segment LED.
39
Vcc
In
+5V source.
41~56
P26/A14~P10/A0
Out
Address bus.
48
Vss
In
Ground(0V) source.
57~64
P30/D0~P37/D7
In/Out Data bus.