K60P100M100SF2RM Datasheet, PDF (1045/1809 Pages) Freescale Semiconductor, Inc – K60 Sub-Family Reference Manual

FTM counter
channel (n) input
(after the filter
channel input)
DECAPEN bit
Chapter 39 FlexTimer (FTM)
2
1
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set DECAPEN
DECAP bit
set DECAP
C(n)V
1
3
5
7
9
15
19
CH(n)F bit
clear CH(n)F
C(n+1)V
2
4
6
8
10
16
20
22
24
CH(n+1)F bit
clear CH(n+1)F
problem 1 problem 2
Note
- The commands set DECAPEN, set DECAP, clear CH(n)F, and clear CH(n+1)F are made by the user.
- Problem 1: channel (n) input = 1, set DECAP, not clear CH(n)F, and clear CH(n+1)F.
- Problem 2: channel (n) input = 1, set DECAP, not clear CH(n)F, and not clear CH(n+1)F.
Figure 39-245. Dual Edge Capture – One-Shot Mode for Positive Polarity Pulse Width
Measurement
The following figure shows an example of the dual edge capture – continuous mode used
to measure the positive polarity pulse width. The DECAPEN bit selects the dual edge
capture mode, so it keeps set in all operation mode. While the DECAP bit is set the
configured measurements are made. The CH(n)F bit is set when the first edge of the
positive polarity pulse is detected, that is, the edge selected by ELS(n)B:ELS(n)A bits.
The CH(n+1)F bit is set when the second edge of this pulse is detected, that is, the edge
selected by ELS(n+1)B:ELS(n+1)A bits. The CH(n+1)F bit indicates when two edges of
the pulse were captured and the C(n)V and C(n+1)V registers are ready for reading.
K60 Sub-Family Reference Manual, Rev. 6, Nov 2011
Freescale Semiconductor, Inc.
1045