Texas Instruments TMS570LC4357

Action-qualifier(AQ)Module
AQCTLA[15:0]
Action-qualifiercontrolA
EPWMA
EPWMB
TBCLK
CTR=PRD
CTR=Zero
CTR=CMPA
CTR=CMPB
CTR_dir
AQCTLB[15:0]
Action-qualifiercontrolB
AQSFRC[15:0]
Action-qualifierS/Wforce
AQCSFRC[3:0](shadow)
continuousS/Wforce
AQCSFRC[3:0](active)
continuousS/Wforce
ePWM Submodules www.ti.com
2016
SPNU563A–March 2018
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Enhanced Pulse Width Modulator (ePWM) Module
The action-qualifier submodule is based on event-driven logic. It can be thought of as a programmable
cross switch with events at the input and actions at the output, all of which are software controlled via the
set of registers shown in Table 35-7.
Figure 35-18. Action-Qualifier Submodule Inputs and Outputs
The possible input events are summarized again in Table 35-8.
Table 35-8. Action-Qualifier Submodule Possible Input Events
Signal Description Registers Compared
CTR = PRD Time-base counter equal to the period value TBCTR = TBPRD
CTR = Zero Time-base counter equal to zero TBCTR = 0x0000
CTR = CMPA Time-base counter equal to the counter-compare A TBCTR = CMPA
CTR = CMPB Time-base counter equal to the counter-compare B TBCTR = CMPB
Software forced event Asynchronous event initiated by software
The software forced action is a useful asynchronous event. This control is handled by registers AQSFRC
and AQCSFRC.
The action-qualifier submodule controls how the two outputs EPWMxA and EPWMxB behave when a
particular event occurs. The event inputs to the action-qualifier submodule are further qualified by the
counter direction (up or down). This allows for independent action on outputs on both the count-up and
count-down phases.
The possible actions imposed on outputs EPWMxA and EPWMxB are:
• Set High:
Set output EPWMxA or EPWMxB to a high level.
• Clear Low:
Set output EPWMxA or EPWMxB to a low level.
• Toggle:
If EPWMxA or EPWMxB is currently pulled high, then pull the output low. If EPWMxA or EPWMxB is
currently pulled low, then pull the output high.