Information

FTMx_SC field descriptions (continued)
Field Description
If another FTM overflow occurs between the read and write operations, the write operation has no effect;
therefore, TOF remains set indicating an overflow has occurred. In this case, a TOF interrupt request is
not lost due to the clearing sequence for a previous TOF.
0 FTM counter has not overflowed.
1 FTM counter has overflowed.
6
TOIE
Timer Overflow Interrupt Enable
Enables FTM overflow interrupts.
0 Disable TOF interrupts. Use software polling.
1 Enable TOF interrupts. An interrupt is generated when TOF equals one.
5
CPWMS
Center-Aligned PWM Select
Selects CPWM mode. This mode configures the FTM to operate in Up-Down Counting mode.
This field is write protected. It can be written only when MODE[WPDIS] = 1.
0 FTM counter operates in Up Counting mode.
1 FTM counter operates in Up-Down Counting mode.
4–3
CLKS
Clock Source Selection
Selects one of the three FTM counter clock sources.
This field is write protected. It can be written only when MODE[WPDIS] = 1.
00 No clock selected. This in effect disables the FTM counter.
01 System clock
10 Fixed frequency clock
11 External clock
2–0
PS
Prescale Factor Selection
Selects one of 8 division factors for the clock source selected by CLKS. The new prescaler factor affects
the clock source on the next system clock cycle after the new value is updated into the register bits.
This field is write protected. It can be written only when MODE[WPDIS] = 1.
000 Divide by 1
001 Divide by 2
010 Divide by 4
011 Divide by 8
100 Divide by 16
101 Divide by 32
110 Divide by 64
111 Divide by 128
35.3.4 Counter (FTMx_CNT)
The CNT register contains the FTM counter value.
Memory map and register definition
K20 Sub-Family Reference Manual, Rev. 2, Feb 2012
698 Freescale Semiconductor, Inc.