Casio CTK-750 Manuale Utente
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DAC (UPD6376CX)
UPD6376CX is a two-channel 16-bit Digital to Analog Convertor consisting of resistor string, output
amplifier and zero offset circuit.
amplifier and zero offset circuit.
Key Touch LSI (HG52E35P)
By counting the time between first-key input signal FI and second-key SI from the keyboard unit, the key
touch LSI detects key velocity of 256-step. Then the LSI sends the CPU the note number and its velocity
data.
touch LSI detects key velocity of 256-step. Then the LSI sends the CPU the note number and its velocity
data.
RESB
CCSB
CWRB
CRDB
CKI
CD0
CD7
CA0 ~ CA2
First contact
Second contact
KC0
KC7
FI0
FI7
SI0
SI7
Key input signal
Key scan signal
~
Data bus
Address bus
Reset signal from the CPU
Chip select signal from the gate array
Read enable signal from the gate array
Write enable signal from the gate array
Clock from the gate array
Chip select signal from the gate array
Read enable signal from the gate array
Write enable signal from the gate array
Clock from the gate array
Key touch LSI
HG52E35P
HG52E35P
Keyboard
FI
SI
KC
Pin No.
Terminal
In/Out
Function
1
SEL
In
Mode selection terminal. Connected to ground.
2
D.GND
In
Ground (0V) source for internal digital circuit
3
NC
Not used.
4
DVDD
In
+5V source for internal digital circuit
5
A.GND
In
Ground (0V) source for internal analog circuit
6
R.OUT
Out
Sound waveform output
7
A.VDD
In
+5V source for internal analog circuit
8
A.VDD
In
+5V source for internal analog circuit
9
R.REF
In
Reference voltage terminal. Connected to a capacitor.
10
L.REF
In
Reference voltage terminal. Connected to a capacitor.
11
L.OUT
Out
Left channel sound waveform output
12
A.GND
In
Ground (0V) source for internal analog circuit
13
LRCK
In
Word clock (L/R separation signal) input.
14
LRSEL
In
Not used. Connected to ground.
15
SI
In
Sound data input
16
CLK
In
Bit clock input