gc80c510 CORERIVER Semiconductor, gc80c510 Datasheet - Page 73

• Manufacturer Part Number: gc80c510
• Description: Eprom/rom 8-bit Turbo Microcontrollers
• Manufacturer: CORERIVER Semiconductor

6.2.7.1
MiDAS1.1 Family
The ADC module's input pins are alternatively used as digital input in P0[7:1] and P2[6:2].
When ADC channel input pins are used for ADC, they must be configured as analog input. So, you
should turn off the pull-up resistor on analog input pins. To turn off the pull-up resistor, set the pull-up
resistor control bits that are P0SEL[7:0] and P2SEL[6:2] to “1’.
voltage. The default setting for reference voltage level is V
remain within the range of V
you set the bit in ADCON[3] to “1”. The analog input voltage level must remain within the range of V
to AV
conversion process for each conversion step. The reference voltage level for the first bit conversion is
always 1/2 ADC reference voltage level (1/2 V
Figure 6-15 ADC Circuit Diagram
In the ADC function block
If the analog input voltage level is compared to the ADC reference voltage level (AV
Different reference voltage levels are generated internally along the resistor tree during the analog
ADC11
ADC0
ADC1
AV
(P0.1)
(P0.2)
(P2.2)
(P0.4)
REF
REF
Reference Voltage Levels
.
Note that AV
ADC11B
ADC0B
ADC1B
Analog
CH[3:0]
REF
MUX
is the voltage level 2V ~ V
SS
(Figure
to V
AD_EN
AV
DD
Control
Circuit
REF
.
6-15), the analog input voltage level is compared to the reference
AD_REQ
1
D/A Converter
Page 73 of 211
DD
V
0
DD
or 1/2 AV
V
DD
SS
Analog
Comparator
.
REF
DD
ADIV
)
9
. And the analog input voltage level must
.
8
PWM Clock (F
7
ADCR
Approximation
6
Successive
5
Register
1
4
3 2
0
F
SAR[9:0]
SAR[9:2]
ADC
PWM
)
except for F
F
OSC
/ 2
ADCON
AD_END
ADCF
ADC Interrupt Flag
REF
OSC
SAR[1:0]
/1
) from P0[4],
1 0
SS