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0x0000
0xFFFF
CTR=CMPA
TBCTR[15:0]
CMPA
(value)
CMPB
(value)
TBPHS
(value)
TBPRD
(value)
CTR=CMPB
EPWMxSYNCI
TBCTR[15:0]
0x0000
0xFFFF
CTR=CMPA
CMPA
(value)
CMPB
(value)
TBPHS
(value)
TBPRD
(value)
CTR=CMPB
EPWMxSYNCI
Counter-Compare (CC) Submodule
• Up-down-count mode: used to generate a symmetrical PWM waveform.
To best illustrate the operation of the first three modes, the timing diagrams in Figure 2-13 through
Figure 2-16 show when events are generated and how the EPWMxSYNCI signal interacts.
Figure 2-13. Counter-Compare Event Waveforms in Up-Count Mode
NOTE: An EPWMxSYNCI external synchronization event can cause a discontinuity in the TBCTR count
sequence. This can lead to a compare event being skipped. This skipping is considered normal operation
and must be taken into account.
Figure 2-14. Counter-Compare Events in Down-Count Mode
SPRU791D – November 2004 – Revised October 2007 ePWM Submodules 35
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