Adc Extended Configuration Registers (Adcexcfg) - STC micro STC8A8K64D4 Series Reference Manual

STC8A8K64D4 Series Manual
ADC clock F
ADC
SYSclk/2/(SPEED+1)
Enable signal of
ADC_POWER
Start signal
ADC_START
Finishing sigal
ADC_FLAG
Analog input channel
ADCx_IN
Begin selecting channel

17.1.5 ADC Extended configuration registers (ADCEXCFG)

Symbol Address
ADCEXCFG FEADH
ADCETRS[1:0] : ADC external trigger pin ADC_ETR control bit
ADCETRS[1:0]
0x
10 Enable ADC_ETR rising edge to trigger ADC
11 Enable ADC_ETR falling edge to trigger ADC
Note: Before using this function, the ADC power switch in ADC_CONTR must be turned on, and the
corresponding ADC channel must be set
[2:0] : ADC automatic conversion times selection
CVTIMESEL
[2:0]
CVTIMESEL
0xx
100
101
110
111
Note: When the ADC automatic many conversions function is enabled, the ADC interrupt flag will only be set
to 1 after the ADC automatically converts to the set number of times (for example, set CVTIMESEL to 101B,
that is, the ADC automatically converts 4 times and takes the average value, the ADC interrupt flag will be set
to 1 after every 4 ADC conversions completed)
Begin End
sampling sampling
采样时间T
duty
(SMPDUTY+1)
Preparation
time T
setup
(CSSETUP+1)
The whole timing Diagram Of ADC
B7 B6
- -
ADC_ETR configure
Diable ETR function
ADC automatic conversion times
One time
Convert 2 times and take the average
Convert 4 times and take the average
Convert 8 times and take the average
Convert 16 times and take the average
Close channel and
begin conversion
Conversion time T
(10位ADC为10个ADC时钟)
(12位ADC为12个ADC时钟)
Holding time T
hold
(CSHOLD+1)
B5 B4 B3
ADCETRS[1:0]
Conversion
finish
convert
B2 B1
- CVTIMESEL[2:0]
B0
- 485 -