DAC (LSI104: UPD6376GS)
The DAC receives
The following table shows the pin functions of LSI1.
Pin No. | Terminal | In/Out | Function | ||
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1 | SEL |
| In | Mode selection terminal. Connected to ground. | |
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2 | D.GND |
| In | Ground (0V) source for the internal digital circuit | |
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3 | NC |
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| Not used. |
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4 | DVDD |
| In | +5V source for the internal digital circuit | |
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5 | A.GND |
| In | Ground (0V) source for the right channel | |
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6 | R.OUT |
| Out | Right channel sound waveform output | |
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7, 8 | A.VDD |
| In | +5V source for the internal analog circuit | |
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9 | R.REF |
| In | Right channel reference voltage terminal | |
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10 | L.REF |
| In | Left channel reference voltage terminal | |
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11 | L.OUT |
| Out | Left channel sound waveform output | |
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12 | A.GND |
| In | Ground (0V) source for the left channel | |
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13 | LRCK |
| In | Word clock input | |
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14 | LRSEL |
| In | Not used. Connected to ground. | |
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15 | SI |
| In | Sound data input | |
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16 | CLK |
| In | Bit clock input | |
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KEY CONTROLLER (LSI107: HG52E35P)
The key controller generates key scan signals and provides them to the keyboard. By counting the time between
RD
APO
WR
CLOCK
A13
A14
RESET
Data bus
Address bus
Key Controller
LSI107
HG52E35P
CRDB
CWRB KC0 CKI
CCSB KC7
RESB FI0
CD0 SI0
CD7
FI7
CA0 ~ CA2 SI7
Key scan signal
Key input signal
Keyboard |
KC |
First contact |
FI |
SI |
Second contact |
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