Datasheet

DOWN

TBCTR

TBCTRDirection

EPWMxA/EPWMxB

Case2:

CMPA =3,25%Duty

Case3:

CMPA =2,50%Duty

Case3:

CMPA =1,75%Duty

Case4:

CMPA =0,100%Duty

Case1:

CMPA =4,0%Duty

EPWMxA/EPWMxB

Mode:Up-DownCount

TBPRD=4

CAU=SET,CAD=CLEAR

0%-100%Duty

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ePWM Submodules

Figure 34-20. Up-Down-Count Mode Symmetrical Waveform

The PWM waveforms in Figure 34-21 through Figure 34-26 show some common action-qualifier

configurations. The C-code samples in Example 34-1 through Example 34-6 shows how to configure an

ePWM module for each case. Some conventions used in the figures and examples are as follows:

• TBPRD, CMPA, and CMPB refer to the value written in their respective registers. The active register,

not the shadow register, is used by the hardware.

• CMPx, refers to either CMPA or CMPB.

• EPWMxA and EPWMxB refer to the output signals from ePWMx

• Up-Down means Count-up-and-down mode, Up means up-count mode and Dwn means down-count

mode

• Sym = Symmetric, Asym = Asymmetric

Example 34-1 contains a code sample showing initialization and run time for the waveforms in Figure 34-

21.

1737

SPNU562–May 2014 Enhanced Pulse Width Modulator (ePWM) Module

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