MC68HC908LK24 MOTOROLA [Motorola, Inc], MC68HC908LK24 Datasheet - Page 335

• Manufacturer Part Number: MC68HC908LK24
• Description: Microcontrollers
• Manufacturer: MOTOROLA [Motorola, Inc]

16.4 Functional Descriptions
16.4.1 ADC Port I/O Pins
MC68HC908LJ24/LK24 — Rev. 2
MOTOROLA
Addr.
$003C
$003D
$003E
$003F
ADC Data Register High
ADC Status and Control
ADC Data Register Low
Register Name
ADC Clock Register
(ADSCR)
(ADCLK)
Register
(ADRH)
(ADRL)
The ADC provides six pins for sampling external sources at pins
PTA4/ADC0–PTA7/ADC3 and PTB6/ADC4–PTB7/ADC5. An analog
multiplexer allows the single ADC converter to select one of ten ADC
channels as ADC voltage in (V
successive approximation register-based analog-to-digital converter.
When the conversion is completed, ADC places the result in the ADC
data register, high and low byte (ADRH and ADRL), and sets a flag or
generates an interrupt.
Figure 16-2
PTA4–PTA7 and PTB6–PTB7 are general-purpose I/O pins that are
shared with the ADC channels. The channel select bits, ADCH[4:0],
define which ADC channel/port pin will be used as the input signal. The
ADC overrides the port I/O logic by forcing that pin as input to the ADC.
The remaining ADC channels/port pins are controlled by the port I/O
Reset:
Reset:
Reset:
Reset:
Read:
Read:
Read:
Read:
Write:
Write:
Write:
Write:
Figure 16-1. ADC I/O Register Summary
Freescale Semiconductor, Inc.
For More Information On This Product,
COCO
ADIV2
Bit 7
ADx
ADx
Analog-to-Digital Converter (ADC)
R
R
0
0
0
0
Go to: www.freescale.com
shows the structure of the ADC module.
= Unimplemented
ADIV1
AIEN
ADx
ADx
R
R
6
0
0
0
0
ADCO
ADIV0
ADx
ADx
R
R
5
0
0
0
0
ADIN
ADICLK
ADCH4
ADx
ADx
R
R
4
1
0
0
0
). V
ADIN
MODE1
ADCH3
ADx
ADx
R
R
R
3
1
0
0
0
Analog-to-Digital Converter (ADC)
is converted by the
= Reserved
MODE0
ADCH2
ADx
ADx
R
R
2
1
0
0
1
Functional Descriptions
ADCH1
ADx
ADx
R
R
1
1
0
0
0
0
Data Sheet
ADCH0
Bit 0
ADx
ADx
R
R
R
1
0
0
0
0
335