Casio CTK-630 Manual De Usuario
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CPU (LSI105: UPD912GF-3BA)
The 16-bit CPU contains a 1k-byte RAM, three 8-bit I/O ports, two timers, a keycontroller 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 LSI105.
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 LSI105.
Pin No.
Terminal
In/Out
Function
1
TXD0
Out
MIDI signal input
2
RXD0
In
MIDI signal output
3
SCK0
Out
APO (Auto Power Off) signal output
4, 5
TXD1, RXD2
—
Not used. Connected to ground.
6
SCK1
Out
1 MHZ synchronizing pulse output
7
AVCC
In
Ground (0 V) source
8, 9
AN0, AN1
—
Not used. Connected to ground.
10
AGND
In
Ground (0 V) source
11
BCK
Out
Bit clock output
12
SO
Out
Serial sound data output
13
LRCK
Out
Word clock output
14
GND
In
Ground (0 V) source
15, 16
XLT0, XLT1
In/Out
20 MHz clock input/output
17
VCC
In
+5 V source
18, 19
MD0, MD1
In
Mode selection terminal
20
RSTB
In
Reset signal input
21
NMI
In
Power ON signal input
22
INT
—
Not used. Connected to ground.
23 ~ 30
FI0 ~ FI3
SI0 ~ SI3
SI0 ~ SI3
In
Terminal for key input signal
31 ~ 38
KC0 ~ KC7
Out
Terminal for key scan signal
39 ~ 46
FI4 ~ FI7
SI4 ~ SI7
SI4 ~ SI7
In
Terminal for key input signal
47, 48
FI8, SI8
In
Terminal for pad input signal
49
FI9
In
Terminal for button input signal
50
SI9
In
Sustain signal input
51
FI10
In
Terminal for button input signal
52
SI10
In
Not used
53 ~ 55
KI0 ~ KI2
In
Terminal for button input signal
56
MWNB
Out
Write enable signal output
57 ~ 76
MA0 ~ MA17
Out
Address bus
77
MCSB0
Out
Chip enable signal output for the sound source ROM
78
MCSB1
Out
Not used
79
MCSB2
Out
Chip enable signal output for the DSP