NXP Semiconductors MKW01Z128, Reference Manual

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SCR[IER] and SCR[IEF] are used to select the condition which will cause the CMP
module to assert an interrupt to the processor. SCR[CFF] is set on a falling-edge and
SCR[CFR] is set on rising-edge of the comparator output. The optionally filtered CMPO
can be read directly through SCR[COUT].
25.3.1 CMP functional modes
There are the following main sub-blocks to the CMP module:
• The comparator itself
• The filter function
The filter, CR0[FILTER_CNT], can be clocked from an internal clock source only. The
filter is programmable with respect to the number of samples that must agree before a
change in the output is registered. In the simplest case, only one sample must agree. In
this case, the filter acts as a simple sampler.
The comparator filter and sampling features can be combined as shown in the following
table. Individual modes are discussed below.
Table 25-1. Comparator sample/filter controls
Mode # CR1[EN] CR1[WE] CR1[SE]
CR0[FILTER_C
NT]
FPR[FILT_PER] Operation
1 0 X X X X
Disabled
See the Disabled mode (# 1) .
2A 1 0 0 0x00 X
Continuous Mode
See the Continuous mode (#s 2A &
2B) .
2B 1 0 0 X 0x00
3B 1 0 0 0x01 > 0x00 Sampled, Non-Filtered mode
See the Sampled, Non-Filtered
mode (#s 3B)
.
4B 1 0 0 > 0x01 > 0x00 Sampled, Filtered mode
See the Sampled, Filtered mode (#s
4B) .
All other combinations of CR1[EN], CR1[WE], CR1[SE], CR0[FILTER_CNT], and FPR[FILT_PER] are illegal.
For cases where a comparator is used to drive a fault input, for example, for a , it must be
configured to operate in Continuous mode so that an external fault can immediately pass
through the comparator to the target fault circuitry.
Functional description
MKW01Z128 MCU Reference Manual, Rev. 3, 04/2016
492 Freescale Semiconductor, Inc.