SPRUJD3A July 2025 – October 2025 F28E120SB , F28E120SC
The action-qualifier submodule operation is shown in Figure 15-18 and monitored by way of the registers in Section 15.12.
For convenience, the possible input events are summarized again in Table 15-4.
Figure 15-18 Action-Qualifier
Submodule Inputs and Outputs
| Signal | Description | Registers Compared |
|---|---|---|
| CTR = PRD | Time-base counter equal to the period value | TBCTR = TBPRD |
| CTR = Zero | Time-base counter equal to 0 | TBCTR = 0x00 |
| CTR = CMPA | Time-base counter equal to the counter-compare A | TBCTR = PWMx_CMPA |
| CTR = CMPB | Time-base counter equal to the counter-compare B | TBCTR = PWMx_CMPB |
| Software forced event | Asynchronous event initiated by software |
The software forced action is a useful asynchronous event. This control is handled by the PWMx_AQSFRC and PWMx_AQOTSFRC register.
The action-qualifier submodule controls how the outputs MCPWMx_yA and MCPWMx_yB 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 MCPWMx_yA and MCPWMx_yB are:
Actions are specified independently for either output (MCPWMx_yA or MCPWMx_yB). Any or all events can be configured to generate actions on a given output. For example, both CTR = PWMx_CMPA and CTR = PWMx_CMPB can operate on output MCPWMx_yA. For each PWM pair "x", independent action qualifier events are specified. All qualifier actions are configured using the control registers found in Section 15.12.
For clarity, the illustrations in this chapter use a set of symbolic actions. These symbols are summarized in Figure 15-19. 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 the time positions are programmed by way of the counter-compare A and B registers, respectively. To turn off or disable an action, use the "Do Nothing option"(the default at reset).
Figure 15-19 Possible
Action-Qualifier Actions for MCPWMx_yA and MCPWMx_yB Outputs