The PWM module of AM263x inherited features from TI classic C28 controllers. With a unique XBAR architecture of AM263x, its ADC SOC triggers are able to trigger not only ADC events but also various of other events like DMA. This part will give some details on how to synchronize PWM modules and how to configure PWM modules to trigger ADC and DMA. More details can be found in Technical Reference Manual.
Figure 2-18 presents a summary of ePWM7, which is used to trigger DMA for resolver excitation signal updating at 200 kHz via DAC. There are couple tabs available for configuration. But, for the DMA trigger purpose, there are only three tabs to be updated.
Figure 2-19 shows details on Time Base. EPWM7 is configured as 200 kHz, Up-Count, and following Sync Out Pulse from ePWM0. It is worth attention that peripherals are operated at 200 MHz while R5F cores are running at 400 MHz.
Figure 2-20 shows details on Event Trigger. The key contents are listed below. ePWM7 is to generate two triggers, ADC SOCA and SOCB. The two triggers are from different source events The one related to CMPA is configured in the Counter Compare tab as shown in Figure 2-21.
EPWM0 is used as Phase A of traction inverter. All EPWM channels are synchronized to EPWM0. It is configured as 10 kHz, Up-Down Count, No Sync In, Sync Out and ADC SOC trigger at counter zero as shown by Figure 2-22 and Figure 2-23.
Dead-Band of EPWM0 is configured as Figure 2-24. Delay value of 200 indicates 1000 ns because of the 200 MHz peripherals clock.