If (CnV = 0x0000) then the channel (n) output is a 0% duty cycle CPWM signal.
If (CnV > MOD), then the channel (n) output is a 100% duty cycle CPWM signal,
although the CHnF bit is set when the counter changes from incrementing to
decrementing. Therefore, MOD must be less than 0xFFFF in order to get a 100% duty
cycle CPWM signal.
27.4.8 Registers Updated from Write Buffers
27.4.8.1 MOD Register Update
If (CMOD[1:0] = 0:0) then MOD register is updated when MOD register is written.
If (CMOD[1:0] ≠ 0:0), then MOD register is updated according to the CPWMS bit, that
is:
• If the selected mode is not CPWM then MOD register is updated after MOD register
was written and the TPM counter changes from MOD to zero.
• If the selected mode is CPWM then MOD register is updated after MOD register was
written and the TPM counter changes from MOD to (MOD – 1).
27.4.8.2 CnV Register Update
If (CMOD[1:0] = 0:0) then CnV register is updated when CnV register is written.
If (CMOD[1:0] ≠ 0:0), then CnV register is updated according to the selected mode, that
is:
• If the selected mode is output compare then CnV register is updated on the next TPM
counter increment (end of the prescaler counting) after CnV register was written.
• If the selected mode is EPWM then CnV register is updated after CnV register was
written and the TPM counter changes from MOD to zero.
• If the selected mode is CPWM then CnV register is updated after CnV register was
written and the TPM counter changes from MOD to (MOD – 1).
Chapter 27 Timer/PWM Module (TPM)
KL02 Sub-Family Reference Manual, Rev. 2.1, July 2013
Freescale Semiconductor, Inc.
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