ePWM Submodules
690
SPRUH22I – April 2012 – Revised November 2019
Copyright © 2012–2019, Texas Instruments Incorporated
C28 Enhanced Pulse Width Modulator (ePWM) Module
Table 7-21. Possible Actions On a Trip Event
TZCTL Register bit-field
Settings
EPWMxA
and/or
EPWMxB
Comment
0,0
High-Impedance
Tripped
0,1
Force to High State
Tripped
1,0
Force to Low State
Tripped
1,1
No Change
Do Nothing.
No change is made to the output.
Example 7-7. Trip-Zone Configurations
Scenario A:
A one-shot trip event on TZ1 pulls both EPWM1A, EPWM1B low and also forces EPWM2A and EPWM2B
high.
•
Configure the ePWM1 registers as follows:
–
TZSEL[OSHT1] = 1: enables TZ1 as a one-shot event source for ePWM1
–
TZCTL[TZA] = 2: EPWM1A will be forced low on a trip event.
–
TZCTL[TZB] = 2: EPWM1B will be forced low on a trip event.
•
Configure the ePWM2 registers as follows:
–
TZSEL[OSHT1] = 1: enables TZ1 as a one-shot event source for ePWM2
–
TZCTL[TZA] = 1: EPWM2A will be forced high on a trip event.
–
TZCTL[TZB] = 1: EPWM2B will be forced high on a trip event.
Scenario B:
A cycle-by-cycle event on TZ5 pulls both EPWM1A, EPWM1B low.
A one-shot event on TZ1 or TZ6 puts EPWM2A into a high impedance state.
•
Configure the ePWM1 registers as follows:
–
TZSEL[CBC5] = 1: enables TZ5 as a one-shot event source for ePWM1
–
TZCTL[TZA] = 2: EPWM1A will be forced low on a trip event.
–
TZCTL[TZB] = 2: EPWM1B will be forced low on a trip event.
•
Configure the ePWM2 registers as follows:
–
TZSEL[OSHT1] = 1: enables TZ1 as a one-shot event source for ePWM2
–
TZSEL[OSHT6] = 1: enables TZ6 as a one-shot event source for ePWM2
–
TZCTL[TZA] = 0: EPWM2A will be put into a high-impedance state on a trip event.
–
TZCTL[TZB] = 3: EPWM2B will ignore the trip event.
7.2.7.4
Generating Trip Event Interrupts
and
illustrate the trip-zone submodule control and interrupt logic, respectively.
DCAEVT1/2 and DCBEVT1/2 signals are described in further detail in