mc68hc908gr8a Freescale Semiconductor, Inc, mc68hc908gr8a Datasheet - Page 51

• Manufacturer Part Number: mc68hc908gr8a
• Description: M68hc08 Microcontrollers Microcontroller
• Manufacturer: Freescale Semiconductor, Inc

3.6 I/O Signals
The ADC module has six pins shared with port B, PTB5/AD5–PTB0/KBD0.
3.6.1 ADC Analog Ground Pin (V
The ADC analog portion uses V
Connect the V
3.6.2 ADC Analog Power Pin (V
The ADC analog portion uses V
Connect the V
3.6.3 ADC Voltage In (V
V
3.7 I/O Registers
These I/O registers control and monitor ADC operation:
3.7.1 ADC Status and Control Register
Function of the ADC status and control register (ADSCR) is described here.
COCO — Conversions Complete Bit
Freescale Semiconductor
ADIN
•
•
•
In non-interrupt mode (AIEN = 0), COCO is a read-only bit that is set at the end of each conversion.
COCO will stay set until cleared by a read of the ADC data register. Reset clears this bit.
is the input voltage signal from one of the six ADC channels to the ADC module.
ADC status and control register (ADSCR)
ADC data register (ADR)
ADC clock register (ADCLK)
Address:
SSAD
DDAD
For maximum noise immunity, route V
bypass capacitors as close as possible to the package. Routing V
close and parallel to V
For maximum noise immunity, route V
bypass capacitors as close as possible to the package. Routing V
close and parallel to V
Reset:
Read:
Write:
/V
/ V
REFL
REFH
$003C
COCO
Figure 3-3. ADC Status and Control Register (ADSCR)
Bit 7
R
R
0
pin to the same voltage potential as V
MC68HC908GR8A • MC68HC908GR4A Data Sheet, Rev. 5
pin to the same voltage potential as V
ADIN
= Reserved
SSAD
DDAD
AIEN
)
6
0
DDAD
REFL
REFL
as its ground pin and V
as its power pin and V
SSAD
)/ADC Voltage Reference High Pin (V
ADCO
may improve common mode noise rejection.
may improve common mode noise rejection.
5
0
)/ADC Voltage Reference Low Pin (V
NOTE
NOTE
ADCH4
4
1
SSAD
DDAD
/V
/V
ADCH3
REFH
REFL
REFH
3
1
REFL
SS
carefully and place
as its upper voltage reference pin.
DD
as its lower voltage reference pin.
carefully and place
.
ADCH2
.
2
1
ADCH1
1
1
REFH
REFH
REFH
)
ADCH0
Bit 0
REFL
1
)
I/O Signals
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