MC68HC12 MOTOROLA [Motorola, Inc], MC68HC12 Datasheet - Page 369

• Manufacturer Part Number: MC68HC12
• Description: The MC68HC912DT128A microcontroller unit (MCU) is a 16-bit device composed of standard on-chip peripherals including a 16-bit central processing unit
• Manufacturer: MOTOROLA [Motorola, Inc]

19.3 Modes of Operation
MC68HC912DT128A — Rev 4.0
MOTOROLA
Analog to digital conversions are performed in a variety of different
programmable sequences referred to as conversion modes. Each
conversion mode is defined by:
The modes are defined by the settings of three control bits (in ATDCTL5)
and three control values
Sequences are initiated or halted by writing to control registers
ATDCTL4 and ATDCTL5.
For the continuous sequence modes, conversions will not stop until
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How many A/D conversions (one, four or eight) are performed in
a sequence
Which analog input channels are examined during a sequence
The sample time length
Whether sequences are performed continuously or not
Result register assignments
MULT controls whether the sequence examines a single analog
input channel or scans a number of different channels
SCAN determines if sequences are performed continuously
SC determines if we are performing a special conversion i.e.
converting V
CC/CB/CA (in ATDCTL5) define the input channel(s) to be
examined
S8C/S1C (in ATDCTL3/5) define the number of conversions in a
sequence
SMP0/SMP1 (in ATDCTL4) define the length of the sample time.
Another non-continuous conversion sequence is initiated and
finishes
The ATD is powered down (ADPU control bit)
The ATD is reset
Analog-to-Digital Converter
RL
, V
RH
, (V
RL
+V
RH
)/2 (usually used for test purposes).
Analog-to-Digital Converter
Modes of Operation
Technical Data
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