handle HLC charging without power and fix AC basic pause transitions

Signed-off-by: Piet Gömpel <pietgoempel@gmail.com>

Author: Pietfried

modules/EVSE/EvseManager/Charger.cpp

@@ -627,14 +627,14 @@ void Charger::run_state_machine() {
                 // In AC mode BASIC, iec_allow is sufficient.  The same is true for HLC mode when nominal PWM is
                 // used as the car can do BASIC and HLC charging any time. In AC HLC with 5 percent mode, we need to
                 // wait for both iec_allow and hlc_allow.
-                if (not power_available()) {
-                    // FIXME: For AC BC, it is ok to wait here. The behaviour we would like to have for AC ISO
-                    // when starting up with no power needs to be defined still. For DC it just continues here without
-                    // power.
+                if (not power_available() and not hlc_use_5percent_current_session) {
+                    //For AC BC: it is ok to wait here.
+                    // For AC and DC ISO, continue in case we are in 5% mode. This allows us to go into
+                    // Charge loop and report 0A/0W to the EV
                     break;
                 }
 
-                // Power is available, PWM is already enabled. Check if we can go to charging
+                // Power is available or we are in HLC, PWM is already enabled. Check if we can go to charging
                 if ((shared_context.iec_allow_close_contactor and not hlc_use_5percent_current_session) or
                     (shared_context.iec_allow_close_contactor and shared_context.hlc_allow_close_contactor and
                      hlc_use_5percent_current_session)) {
@@ -703,18 +703,15 @@ void Charger::run_state_machine() {
                 check_soft_over_current();
 
                 if (not power_available()) {
-
-                    if (shared_context.hlc_charging_active) {
+                    if (shared_context.hlc_charging_active or hlc_use_5percent_current_session) {
+                        // We are in HLC and have no energy
                         // TODO: start timer to stop charging
-                        // FIXME: hlc_charging_active is only set once PowerDelivery.req is received,
-                        // so currently an AC HLC session will stop immediately here if power is not
-                        // available
                     } else {
                         EVLOG_info << "HLC charging not active";
                         // Stop immediately in basic AC mode
-                        shared_context.current_state = EvseState::ChargingPausedEVSE;
+                        set_state(EvseState::StoppingCharging); // Proxy state to ChargingPausedEVSE 
+                        break;
                     }
-                    break;
                 }
 
                 if (initialize_state) {
@@ -800,6 +797,9 @@ void Charger::run_state_machine() {
             if (initialize_state) {
                 if (shared_context.hlc_charging_active and shared_context.flag_transaction_active) {
                     signal_hlc_pause_charging();
+                } else {
+                    // Basic Charging: just turn off PWM
+                    pwm_off();
                 }
                 internal_context.last_charging_paused_evse_reasons = {};
             }
@@ -878,12 +878,7 @@ void Charger::run_state_machine() {
                     }
                     // Car is maybe not unplugged yet, so for HLC(AC/DC) wait in this state. We will go to Finished
                     // once car is unplugged.
-                } else {
-                    // For AC BASIC charging, we reached StoppingCharging because an unplug happend.
-                    pwm_off();
-                    shared_context.current_state = EvseState::Finished;
                 }
-
                 bsp->allow_power_on(false, types::evse_board_support::Reason::PowerOff);
             }
 
@@ -894,7 +889,7 @@ void Charger::run_state_machine() {
                 break;
             }
 
-            if (shared_context.flag_paused_by_evse or stop_charging_on_fatal_error_internal()) {
+            if (not power_available() or shared_context.flag_paused_by_evse or stop_charging_on_fatal_error_internal()) {
                 // Paused was initiated by EVSE, continue to PausedEVSE
                 set_state(EvseState::ChargingPausedEVSE);
                 break;

modules/EVSE/EvseManager/Charger.hpp

@@ -435,7 +435,7 @@ class Charger {
     // after the wake-up sequence.
     static constexpr int STAY_IN_X1_AFTER_TSTEP_EF_MS = 750;
     static constexpr int WAIT_FOR_ENERGY_IN_AUTHLOOP_TIMEOUT_MS = 5000;
-    static constexpr int AC_X1_FALLBACK_TO_NOMINAL_TIMEOUT_MS = 3000;
+    static constexpr int AC_X1_FALLBACK_TO_NOMINAL_TIMEOUT_MS = 10000; // TODO: is this reasonable?
 
     types::evse_manager::EnableDisableSource active_enable_disable_source{
         types::evse_manager::Enable_source::Unspecified, types::evse_manager::Enable_state::Unassigned, 10000};