can a state Q_TRAN to SPUER? like Blinky_on back to Blinky_idle in fllowing code

[hehao9051]

/........................................................................../ QState Blinky_idle(Blinky const me, QEvt const const e) { QState status; switch (e->sig) { case Q_ENTRY_SIG: { BSP_ledOff(); status = Q_HANDLED(); break; } case KEY_POWER_SIG: { status = Q_TRAN(&Blinky_off); break; } default: { status = Q_SUPER(&QHsm_top); break; } } return status; } /........................................................................../ QState Blinky_off(Blinky const me, QEvt const const e) { QState status; switch (e->sig) { case Q_ENTRY_SIG: { BSP_ledOff(); status = Q_HANDLED(); break; } case KEY_POWER_SIG: { status = Q_TRAN(&Blinky_idle); break; } case TIMEOUT_SIG: { status = Q_TRAN(&Blinky_on); break; } default: { status = Q_SUPER(&Blinky_idle); break; } } return status; } /........................................................................../ QState Blinky_on(Blinky const me, QEvt const const e) { QState status; switch (e->sig) { case Q_ENTRY_SIG: { BSP_ledOn(); status = Q_HANDLED(); break; } case KEY_POWER_SIG: { status = Q_TRAN(&Blinky_idle); break; } case TIMEOUT_SIG: { status = Q_TRAN(&Blinky_off); break; } default: { status = Q_SUPER(&Blinky_idle); break; } } return status; }

[quantum-leaps]

Of course. A transition can target any state, including the superstate of the source state and the source state itself (transition to self). This question and any other question of this type is "answered" by the QHsmTst state machine (see Figure 2.11 in the PSiCC2 book).

I would also highly recommend that you watch the video "State Machines Part-8: Semantics of Hierarchical State Machines"

[hehao9051]

static QState Blinky_initial(Blinky const me, void const const par) { /.${AOs::Blinky::SM::initial} / (void)par; / unused parameter / QTimeEvt_armX(&me->timeEvt, BSP_TICKS_PER_SEC/2, BSP_TICKS_PER_SEC/2);

QS_FUN_DICTIONARY(&Blinky_off);
QS_FUN_DICTIONARY(&Blinky_on);

return Q_TRAN(&Blinky_off);

}

/.${AOs::Blinky::SM::off} ................................................./ static QState Blinkyidle(Blinky const me, QEvt const const e) { QState status; switch (e->sig) { /.${AOs::Blinky::SM::off} / case Q_ENTRY_SIG: { PRINTF_S("%s\n", "Blinkyidle entry"); status = Q_HANDLED(); break; } case Q_INIT_SIG: { PRINTF_S("%s\n", "Blinkyidle init"); status = Q_HANDLED(); break; } /.${AOs::Blinky::SM::off::TIMEOUT} / case TIMEOUTSIG: { status = Q_TRAN(&Blinkyon); break; } default: { status = Q_SUPER(&QHsmtop); break; } } return status; }

/.${AOs::Blinky::SM::on} ................................................../ static QState Blinkyon(Blinky const me, QEvt const const e) { QState status; switch (e->sig) { /.${AOs::Blinky::SM::on} / case Q_ENTRY_SIG: { BSPledOn(); status = Q_HANDLED(); break; } /.${AOs::Blinky::SM::on::TIMEOUT} / case TIMEOUTSIG: { status = Q_TRAN(&Blinkyoff); break; } default: { status = Q_SUPER(&Blinkyidle); break; } } return status; } /.$enddef${AOs::Blinky} ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^/

/.${AOs::Blinky::SM::off} ................................................./ static QState Blinkyoff(Blinky const me, QEvt const const e) { QState status; switch (e->sig) { /.${AOs::Blinky::SM::off} / case Q_ENTRY_SIG: { BSPledOff(); status = Q_HANDLED(); break; } /.${AOs::Blinky::SM::off::TIMEOUT} / case TIMEOUTSIG: { status = Q_TRAN(&Blinkyidle); break; } default: { status = Q_SUPER(&Blinkyidle); break; } } return status; }

like this code, when Blinky_off Q_TRAN(&Blinky_idle)，in Blinky_off state , there is no Q_ENTRY_SIG event ,only have Q_INIT_SIG, Is that right? I need help. @quantum-leaps

[quantum-leaps]

It's OK not to provide Q_ENTRY_SIG, Q_EXIT_SIG, or Q_INIT_SIG in a state handler. If you don't have anything to do upon entry, exit, or nested initial transition you simply don't provide that. I hope this clarifies the situation. --MME