PXN20RM Datasheet, PDF (837/1376 Pages) Freescale Semiconductor, Inc – PXN20 Microcontroller

Field
UCPRE
Enhanced Modular Input/Output Subsystem (eMIOS200)
Table 28-10. EMIOS_CCR[n] Field Descriptions (continued)
Description
Prescaler Bits. The UCPRE bits select the clock divider value for the internal prescaler of unified channel.
UCPRE
00
01
10
11
Divide Ratio
1
2
3
4
UCPREN
DMA
IF
Prescaler Enable Bit. The UCPREN bit enables the prescaler counter.
0 Prescaler disabled (no clock) and prescaler counter is loaded with UCPRE value.
1 Prescaler enabled.
Direct Memory Access Bit. The DMA bit selects whether the FLAG generation is used as an interrupt or as a
DMA request.
0 FLAG assigned to interrupt request.
1 FLAG assigned to DMA request.
Input Filter Bits. The IF bits control the programmable input filter, selecting the minimum input pulse width that
can pass through the filter. For output modes, these bits have no meaning.
FCK
FEN
FORCMA
IF¹
Minimum Input Pulse Width
[FLT_CLK Periods]
0000
Bypassed²
0001
02
0010
04
0100
08
1000
16
All others
Reserved
1 _{Filter latency is three clock edges.}
2 _{The input signal is synchronized before arriving to the digital filter.}
Filter Clock Select Bit. The FCK bit selects the clock source for the programmable input filter.
0 Prescaled clock.
1 Main clock.
FLAG Enable Bit. The FEN bit allows the unified channel FLAG bit to generate an interrupt signal or a DMA
request signal (the type of signal to be generated is defined by the DMA bit).
0 Disable (FLAG does not generate an interrupt or DMA request).
1 Enable (FLAG generates an interrupt or DMA request).
Force Match A Bit. For output modes, the FORCMA bit is equivalent to a successful comparison on
comparator A (except that the FLAG bit is not set). This bit is cleared by reset and is always read as 0. This
bit is valid for every output operation mode which uses comparator A, otherwise it has no effect.
0 Has no effect.
1 Force a match at comparator A.
For input modes, the FORCMA bit is not used and writing to it has no effect.
Freescale Semiconductor
PXN20 Microcontroller Reference Manual, Rev. 1
28-15