SN8P2977
8-Bit Micro-Controller with Regulator, PGIA, 24-bit ADC
SONiX TECHNOLOGY CO., LTD
Page 114
Version 1.7
13.6.6
ADCM2- ADC Mode2 Register
094H
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
ADCM2
ADCKS
OSR2
OSR1
OSR0
-
OFSEL1
OFSEL0
DRDY
R/W
R/W
R/W
R/W
R/W
-
R/W
R/W
R/W
After Reset
0
1
1
1
-
1
1
0
Bit7:
ADCKS:
ADC Clock selection Bit.
0 = ADC clock source set 250kHz .
1 = ADC clock source set 333kHz.
Bit[6:4]
OSR [2:0]:
ADC OSR Selection.
Bit[2:1]
OFSEL[1:0]:
ADC Offset selection.
Bit0:
DRDY:
ADC Conversion Ready bit:
1 = ADC output (update) new conversion data to ADCDH, ADCDL, and ADCDLL
0 = ADCDH, ADCDL, and ADCDLL conversion data are not ready.
Note 1: ADC Output Word Rate (WR) = ADC Clock / OSR.
Note 2: Adjust ADC clock (ADCKS) and OSR can get suitable ADC output word rate.
Note 3: For High resolution application, OSR set maximum value of 32768 recommended.
Note 4: Clear Bit DRDY after got ADC data or this bit will keep high all the time.
Note 5: ADC output stable date at the 3
rd
data after ADC enable. The 1
st
ADC output data is dummy after
15us later of ADC enable. The 2
nd
ADC output data is unstable data after 1/WR later of 1
st
ADC data. The 3
rd
,
4
th
, 5
th
… are stable data after 1/WR later of each.
OSR [2:0]
OSR
000
64
001
128
010
256
011
1024
100
4096
101
8192
110
16384
111
32768
OFSEL[1:0]
Off set %
00
-75% Vref
01
-50% Vref
10
-25% Vref
11
00% Vref