Information

fault input n*
system clock
* where n = 3, 2, 1, 0
synchronizer
fault input n* value
FAULTFn*
0000)
and (FFLTRnEN*)
0
1
rising edge
detector
fault input
polarity
control
Fault filter
(5-bit counter)
CLK
CLK
D D
Q
Q
FLTnPOL
(FFVAL[3:0]
Figure 35-192. Fault input n control block diagram
If the fault control and fault input n are enabled and a rising edge at the fault input n
signal is detected, a fault condition has occurred and the FAULTFn bit is set. The
FAULTF bit is the logic OR of FAULTFn[3:0] bits. See the following figure.
fault interrupt
FAULTIE
FAULTIN
fault input 0 value
fault input 1 value
fault input 2 value
fault input 3 value
FAULTF
FAULTF0
FAULTF1
FAULTF2
FAULTF3
Figure 35-193. FAULTF and FAULTIN bits and fault interrupt
If the fault control is enabled (FAULTM[1:0] ≠ 0:0), a fault condition has occurred and
(FAULTEN = 1), then outputs are forced to their safe values:
• Channel (n) output takes the value of POL(n)
• Channel (n+1) takes the value of POL(n+1)
The fault interrupt is generated when (FAULTF = 1) and (FAULTIE = 1). This interrupt
request remains set until:
• Software clears the FAULTF bit by reading FAULTF bit as 1 and writing 0 to it
• Software clears the FAULTIE bit
• A reset occurs
Note
The fault control must be used only in Combine mode.
Chapter 35 FlexTimer Module (FTM)
K20 Sub-Family Reference Manual, Rev. 2, Feb 2012
Freescale Semiconductor, Inc. 789