W83L951DG Datasheet, PDF (84/112 Pages) Winbond – Mobile Keyboard and Embedded Controller

W83L951DG/W83L951FG
6.12 A/D Converter Block
W83L951DG/FG provides 8 A/D inputs. Analog input pin is selected in A/D Converter Register 0.
The A-D conversion register is a read-only register that stores the result of an A-D conversion. When
reading this register during an A-D conversion, the previous conversion result is read.
Table 6-21 A/D Convert Register Define
A/D CONVERT BLOCK(4)
EXTADDR
NAME
7
6
5
4
3
50
AD1
ADCST Analog Input Select ADCC
51
AD2
Analog [9:2]
54
PADMODE AD7
AD6 AD5 AD4 AD3
2
Reserved
AD2
1
0
Analog [1:0]
AD1 AD0
Gray: Only with System Reset to initial.
6.12.1 Register Description
A/D converter is 10-bit converter. The V_REF is Input of VREF pin.
The formula: A/D converter result= (Analog [9:0] / 1024) × V_REF
6.12.1.1 A/D Converter Register 1 (AD1) (Default Value: 0000_00??)
Bit 7: ADC Start Bit
1: Start (Only one time)
0: No change.
When A/D Conversion Complete Status Bit is high, write 1 to this bit to start A/D convert. And ADC
Start Bit keeps low until hardware receives this request and can receive next request. And ADC Start
Bit changes from low to high at the time.
Bit 6~4: Analog Input Pin Select
000: GP60, 001: GP61, 010: GP62, 011: GP63,
100: GP64, 101: GP65, 110: GP66, 111: GP67.
Bit 3: A/D Conversion Complete Status Bit (Read Only)
0: Conversion in progress.
1: Conversion completed.
Bit 2: Reserved
Bit 1~0: A/D Converter Result [1:0]
A/D converter result bit1 is LSB.
When A/D Conversion Complete Status Bit is high, A/D Converter Result is valid.
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