Note
The hardware average function can perform conversions on a
channel while the MCU is in Wait or Normal Stop modes. The
ADC interrupt wakes the MCU when the hardware average is
completed if SC1n[AIEN] was set.
28.4.5 Automatic compare function
The compare function can be configured to check whether the result is less than or
greater-than-or-equal-to a single compare value, or, if the result falls within or outside a
range determined by two compare values. The compare mode is determined by
SC2[ACFGT], SC2[ACREN], and the values in the compare value registers, CV1 and
CV2. After the input is sampled and converted, the compare values in CV1 and CV2 are
used as described in the following table. There are six Compare modes as shown in the
following table.
Table 28-78. Compare modes
SC2[AC
FGT]
SC2[AC
REN]
ADCCV1
relative to
ADCCV2
Function Compare mode description
0 0 — Less than threshold Compare true if the result is less than the
CV1 registers.
1 0 — Greater than or equal to threshold Compare true if the result is greater than or
equal to CV1 registers.
0 1 Less than or
equal
Outside range, not inclusive Compare true if the result is less than CV1
Or the result is greater than CV2.
0 1 Greater than Inside range, not inclusive Compare true if the result is less than CV1
And the result is greater than CV2.
1 1 Less than or
equal
Inside range, inclusive Compare true if the result is greater than or
equal to CV1 And the result is less than or
equal to CV2.
1 1 Greater than Outside range, inclusive Compare true if the result is greater than or
equal to CV1 Or the result is less than or
equal to CV2.
With SC2[ACREN] =1, and if the value of CV1 is less than or equal to the value of CV2,
then setting SC2[ACFGT] will select a trigger-if-inside-compare-range inclusive-of-
endpoints function. Clearing SC2[ACFGT] will select a trigger-if-outside-compare-
range, not-inclusive-of-endpoints function.
If CV1 is greater than CV2, setting SC2[ACFGT] will select a trigger-if-outside-
compare-range, inclusive-of-endpoints function. Clearing SC2[ACFGT] will select a
trigger-if-inside-compare-range, not-inclusive-of-endpoints function.
Chapter 28 Analog-to-Digital Converter (ADC)
KL25 Sub-Family Reference Manual, Rev. 3, September 2012
Freescale Semiconductor, Inc. 493
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