If one of the ePWM modules is not used in HRPWM mode, then it can be dedicated to run the SFO diagnostics for the modules that are running HRPWM mode. Here the single MEP_SF value obtained can be applied to other ePWM modules. This assumes that all HRPWM module’s MEP steps are similar but may not be identical. The ePWM module that is not active in HRPWM mode is still fully operational in conventional PWM mode and can be used to drive PWM pins. The SFO function only makes use of the MEP diagnostics logic. The other ePWM modules operating in HRPWM mode incur only a 3-cycle minimum duty limitation. If the application requires all ePWM modules to have HRPWM capability (i.e., MEP is operational), then the
SFO_MepEn(n) function should run for each of the active ePWM modules with HRPWM capability.
· In the above case, a 6-cycle MEP inactivity zone exists at the start of the PWM period. See Section 2.3.3
on duty cycle range limitation.
· If all ePWM modules are using the same TBCLK prescaler, then it is also possible to run the
SFO_MepEn(n) function for only one ePWM module and to use the SFO return value for the othermodules. In this case only one ePWM module incurs the 6-cycle limitation, and remaining modules incur only a 3-cycle minimum duty limitation. See “Duty cycle limitation” section. This assumes that all HRPWM module’s MEP steps are similar but may not be identical.
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还想问下，如果我有一个占空比变化或者频率变化的pwm信号，我想用28335测这个信号的占空比或者频率，我是用一般的GPIO实现还是用eCAP实现呢？
