mc68hc908gr8vp Freescale Semiconductor, Inc, mc68hc908gr8vp Datasheet - Page 58

• Manufacturer Part Number: mc68hc908gr8vp
• Description: M68hc08 Microcontrollers Microcontroller
• Manufacturer: Freescale Semiconductor, Inc

Analog-to-Digital Converter (ADC)
5.6 I/O Signals
The ADC module has six pins shared with port B, PTB5/AD5–PTB0/ATD0.
5.6.1 ADC Analog Power Pin (V
The ADC analog portion uses V
potential as V
5.6.2 ADC Analog Ground Pin (V
The ADC analog portion uses V
potential as V
5.6.3 ADC Voltage In (V
V
5.7 I/O Registers
These I/O registers control and monitor ADC operation:
5.7.1 ADC Status and Control Register
Function of the ADC status and control register (ADSCR) is described here.
COCO — Conversions Complete Bit
58
ADIN
•
•
•
When the AIEN bit is a logic 0, the COCO is a read-only bit which is set each time a conversion is
completed except in the continuous conversion mode where it is set after the first conversion. This bit
is cleared whenever the ADSCR is written or whenever the ADR is read.
If the AIEN bit is a logic 1, the COCO is a read/write bit which selects the CPU to service the ADC
interrupt request. Reset clears this bit.
1 = Conversion completed (AIEN = 0)
0 = Conversion not completed (AIEN = 0), or CPU interrupt (AIEN = 1)
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)
DD
SS
Address:
capacitors as close as possible to the package.
For maximum noise immunity, route V
Reset:
Read:
.
Write:
. External filtering may be necessary to ensure clean V
$0003C
COCO
Figure 5-2. ADC Status and Control Register (ADSCR)
Bit 7
0
ADIN
MC68HC908GR8 • MC68HC908GR4 Data Sheet, Rev. 7
DDAD
SSAD
AIEN
)
6
0
DDAD
as its ground pin. Connect the V
as its power pin. Connect the V
SSAD
ADCO
5
0
)/ADC Voltage Reference High Pin (V
)/ADC Voltage Reference Low Pin (V
NOTE
ADCH4
4
1
DDAD
ADCH3
carefully and place bypass
3
1
ADCH2
DDAD
2
1
SSAD
DDAD
pin to the same voltage
pin to the same voltage
ADCH1
for good results.
1
1
Freescale Semiconductor
ADCH0
REFH
Bit 0
REFL
1
)
)