VIM
Event Trigger
Module Logic
CTR=Zero
CTR=PRD
CTR=CMPA
EPWMxINTn
CTR=CMPB
CTR_dir
Direction
qualifier
CTRU=CMPA
ETSEL reg
EPWMxSOCA
/n
/n
/n
EPWMxSOCB
ADC
clear
count
count
clear
count
clear
CTRD=CMPA
CTRU=CMPB
CTRD=CMPB
ETPS reg
ETFLG reg
ETCLR reg
ETFRC reg
CTR=Zero or PRD
DCAEVT1.soc
DCBEVT1.soc
From Digital Compare
(DC) Submodule
ePWM Submodules
2045
SPNU563A – March 2018
Copyright © 2018, Texas Instruments Incorporated
Enhanced Pulse Width Modulator (ePWM) Module
The event-trigger submodule monitors various event conditions (the left side inputs to event-trigger
submodule shown in
) and can be configured to prescale these events before issuing an
Interrupt request or an ADC start of conversion. The event-trigger prescaling logic can issue Interrupt
requests and ADC start of conversion at:
•
Every event
•
Every second event
•
Every third event
Figure 35-40. Event-Trigger Submodule Showing Event Inputs and Prescaled Outputs
The key registers used to configure the event-trigger submodule are listed in
.
Table 35-20. Event-Trigger Submodule Registers
Register Name
Address Offset
Shadowed
Description
ETSEL
30h
No
Event-trigger Selection Register
ETFLG
34h
No
Event-trigger Flag Register
ETPS
36h
No
Event-trigger Prescale Register
ETFRC
38h
No
Event-trigger Force Register
ETCLR
3Ah
No
Event-trigger Clear Register
•
ETSEL—This selects which of the possible events will trigger an interrupt or start an ADC conversion
•
ETPS—This programs the event prescaling options mentioned above.
•
ETFLG—These are flag bits indicating status of the selected and prescaled events.
•
ETCLR—These bits allow you to clear the flag bits in the ETFLG register via software.
•
ETFRC—These bits allow software forcing of an event. Useful for debugging or s/w intervention.
A more detailed look at how the various register bits interact with the Interrupt and ADC start of
conversion logic are shown in
, and
.