Information

phase A
phase B
FTM counter
increment/decrement
FTM counter
MOD
CNTIN
0x0000
Time
set TOF
clear TOFDIR
-1
set TOF
clear TOFDIR
-1
-1
-1
-1
-1
-1
-1
-1
-1-1
-1
-1
-1
-1
-1-1
-1
-1
-1
-1
-1
-1
-1
-1
Figure 37-254. FTM Counter Overflow in Down Counting for Quadrature Decoder Mode
37.4.25.1 Quadrature Decoder Boundary Conditions
The following figures are examples of motor jittering which causes the FTM counter
transitions as indicated by these figures. It is expected to observe these behaviors in
motor position control applications.
phase A
phase B
FTM counter
MOD
CNTIN
0x0000
Time
Figure 37-255. Motor Position Jittering in a Mid Count Value
Chapter 37 FlexTimer (FTM)
K20 Sub-Family Reference Manual, Rev. 6, Nov 2011
Freescale Semiconductor, Inc. 973