SPRUIM2H May 2020 – October 2023 AM2431 , AM2432 , AM2434 , AM6411 , AM6412 , AM6421 , AM6422 , AM6441 , AM6442
Table 12-4319 lists the registers used to control and monitor the action-qualifier submodule.
Acronym | Register Description | Address Offset | Shadowed |
---|---|---|---|
EPWM_AQCTLA | Action-Qualifier Control Register For Output A (EPWMxA) | 16h | No |
EPWM_AQCTLB | Action-Qualifier Control Register For Output B (EPWMxB) | 18h | No |
EPWM_AQSFRC | Action-Qualifier Software Force Register | 1Ah | No |
EPWM_AQCSFRC | Action-Qualifier Continuous Software Force | 1Ch | Yes |
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 as shown in Figure 12-2249. The possible input events are summarized again in Table 12-4320.
Signal | Description | Register Bitfield Compared |
---|---|---|
PRD_eq | Time-base counter equal to the period value | TBCNT = TBPRD |
CNT_zero | Time-base counter equal to zero | TBCNT = 0000h |
CMPA_eq | Time-base counter equal to the counter-compare A | TBCNT = CMPA |
CMPB_eq | Time-base counter equal to the counter-compare B | TBCNT = CMPB |
Software forced event | Asynchronous event initiated by software |
The software forced action is a useful asynchronous event. This control is handled by EPWM_AQSFRC and EPWM_AQCSFRC registers.
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:
Actions are specified independently for either output (EPWMxA or EPWMxB). Any or all events can be configured to generate actions on a given output. All qualifier actions are configured via the control registers found at the end of this section.
For clarity, the drawings in this chapter use a set of symbolic actions. These symbols are summarized in Figure 12-2250. Each symbol represents an action as a marker in time. Some actions are fixed in time (zero and period) while the CMPA and CMPB actions are moveable and their time positions are programmed via the counter-compare A and B registers, respectively. To turn off or disable an action, use the "Do Nothing option"; it is the default at reset.