SPRUJ53B April 2024 – September 2024 TMS320F28P550SJ , TMS320F28P559SJ-Q1
The ePWM synchronization scheme allows for increased flexibility of synchronization of the ePWM modules. Each ePWM module has a synchronization input (SYNCI), a synchronization output (SYNCO) and a peripheral synchronization output (SYNCPER). In Figure 19-7, EXTSYNCIN1 is sourced from INPUTXBAR5 and EXTSYNCIN2 is sourced from INPUTXBAR6, which can be configured to select any GPIO as the synchronization input. Refer to Section 19.4.3.4 for a list of all sync inputs including INPUTXBAR5 and INPUTXBAR6. Figure 19-8 shows the sources that can be used for EXTSYNCOUT.
Each ePWM module can be configured to use or ignore the synchronization input. If the TBCTL[PHSEN] bit is set, then the time-base counter (TBCTR) of the ePWM module is automatically loaded with the phase register (TBPHS) contents when one of the following conditions occur:
The delay from internal control module to target modules is given by:
When modifying the TBPHS register during run-time, missed action qualifier events can occur due to sudden jumps in the TBCTR value at the time of the SYNCIN pulse. To recreate the behavior of missed action qualifier events, configure an action qualifier event on a T1 or T2 event on a SYNCIN event. The T1 or T2 action qualifier event must be enabled and disabled during runtime depending on the value of TBPHS.
This feature enables the ePWM module to be automatically synchronized to the time base of another ePWM module. Lead or lag phase control can be added to the waveforms generated by different ePWM modules to synchronize them. In up-down-count mode, the TBCTL[PHSDIR] bit configures the direction of the time-base counter immediately after a synchronization event. The new direction is independent of the direction prior to the synchronization event. The PHSDIR bit is ignored in count-up or count-down modes. See Figure 19-9 through Figure 19-12 for examples.
Clearing the TBCTL[PHSEN] bit configures the ePWM to ignore the synchronization input pulse.