https://github.com/rusefi/alphax-4chan/issues/166

only:alphax_4chan

firmware/config/boards/hellen/alphax-4chan/prepend.txt

@@ -18,6 +18,9 @@
 
 #define show_Hellen_presets true
 #define show_4chan_presets true
+#define ts_show_ign_key_analog_input true
+! todo: insert actual value here!
+#define IGN_KEY_DIVIDER 3
 
 #define TS_TRIGGER_SCOPE_CHANNEL_1_NAME "C2/C3 Crank VR"
 #define TS_TRIGGER_SCOPE_CHANNEL_2_NAME "E5/E6 Cam VR"

firmware/controllers/actuators/main_relay.cpp

@@ -4,6 +4,11 @@
 
 void MainRelayController::onSlowCallback() {
 #if EFI_MAIN_RELAY_CONTROL
+#if defined(IGN_KEY_DIVIDER)
+    if (isAdcChannelValid(engineConfiguration->ignKeyAdcChannel)) {
+      hasIgnitionVoltage = Sensor::getOrZero(SensorType::IgnKeyVoltage) > 5;
+    } else
+#endif // IGN_KEY_DIVIDER
     if (engineConfiguration->ignitionKeyDigitalPin != Gpio::Unassigned) {
         // separate digital input pin just for main relay logic since it's preferred to read voltage from main relay
         // key-on is usually a bit smaller voltage than main relay but sometimes even 1v off!

firmware/hw_layer/mc33816.cpp

@@ -1,6 +1,8 @@
 /*
  * @file mc33816.cpp
  *
+ * TL,DR: GDI
+ *
  * The NXP MC33816 is a programmable gate driver IC for precision solenoid control applications.
  *
  *

firmware/init/sensor/init_vbatt.cpp

@@ -5,23 +5,42 @@
 #include "functional_sensor.h"
 #include "linear_func.h"
 
-static LinearFunc vbattFunc;
 static FunctionalSensor vbattSensor(SensorType::BatteryVoltage, /* timeout = */ MS2NT(100));
+static FunctionalSensor ignBattSensor(SensorType::IgnKeyVoltage, /* timeout = */ MS2NT(100));
 
 void initVbatt() {
-	vbattFunc.configure(0, 0, 1, engineConfiguration->vbattDividerCoeff, 0, 50);
-	vbattSensor.setFunction(vbattFunc);
-
-	if (!isAdcChannelValid(engineConfiguration->vbattAdcChannel)) {
-		return;
+  {
+    static LinearFunc vbattFunc; // static with scoped visibility just to reduce change of code defect
+	  vbattFunc.configure(0, 0, 1, engineConfiguration->vbattDividerCoeff, 0, 50);
+	  vbattSensor.setFunction(vbattFunc);
 	}
 
-	// adcVoltsPerVolt is set to 1.0 because vbatt doesn't go thru the analog input divider
-	AdcSubscription::SubscribeSensor(vbattSensor, engineConfiguration->vbattAdcChannel, /* filter HZ = */ 20, /* adcVoltsPerVolt = */ 1.0f);
+#if defined(IGN_KEY_DIVIDER)
+  {
+    static LinearFunc ignBattFunc; // static with scoped visibility just to reduce change of code defect
+	  ignBattFunc.configure(0, 0, 1, IGN_KEY_DIVIDER, 0, 50);
+	  ignBattSensor.setFunction(ignBattFunc);
+	}
+#endif //	IGN_KEY_DIVIDER
 
-	vbattSensor.Register();
+
+	if (isAdcChannelValid(engineConfiguration->vbattAdcChannel)) {
+	  // adcVoltsPerVolt is set to 1.0 because vbatt doesn't go thru the analog input divider
+	  AdcSubscription::SubscribeSensor(vbattSensor, engineConfiguration->vbattAdcChannel, /* filter HZ = */ 20, /* adcVoltsPerVolt = */ 1.0f);
+	  vbattSensor.Register();
+	}
+
+#if defined(IGN_KEY_DIVIDER)
+	if (isAdcChannelValid(engineConfiguration->ignKeyAdcChannel)) {
+	  AdcSubscription::SubscribeSensor(ignBattSensor, engineConfiguration->ignKeyAdcChannel, /* filter HZ = */ 20, /* adcVoltsPerVolt = */ 1.0f);
+	  ignBattSensor.Register();
+	}
+#endif //	IGN_KEY_DIVIDER
 }
 
 void deinitVbatt() {
 	AdcSubscription::UnsubscribeSensor(vbattSensor, engineConfiguration->vbattAdcChannel);
+#if defined(IGN_KEY_DIVIDER)
+	AdcSubscription::UnsubscribeSensor(ignBattSensor, engineConfiguration->ignKeyAdcChannel);
+#endif //	IGN_KEY_DIVIDER
 }

firmware/integration/rusefi_config.txt

@@ -2213,6 +2213,8 @@ end_struct
 #define SIMULATOR_TUNE_BIN_FILE_NAME "generated/simulator_tune_image.bin"
 
 ! some board files override this value using prepend file
+#define ts_show_ign_key_switch false
+#define ts_show_ign_key_analog_input false
 #define ts_show_hip9011 false
 #define ts_show_tps_sent false
 #define ts_show_inj_diag false

firmware/tunerstudio/rusefi.input

@@ -3783,9 +3783,9 @@ cmd_set_engine_type_default					= "@@TS_IO_TEST_COMMAND_char@@@@ts_command_e_TS_
 ;			Engine->Battery & Alternator
 	dialog = batteryDialog, "Battery Settings",	yAxis
 		field = "vBatt ADC input",						vbattAdcChannel
-		field = "Ignition Key ADC input",               ignKeyAdcChannel
-		field = "Ignition Key Switch",                  ignitionKeyDigitalPin
-		field = "Ignition Key Switch Mode",             ignitionKeyDigitalPinMode
+		field = "Ignition Key ADC input",               ignKeyAdcChannel@@if_ts_show_ign_key_analog_input
+		field = "Ignition Key Switch",                  ignitionKeyDigitalPin@@if_ts_show_ign_key_switch
+		field = "Ignition Key Switch Mode",             ignitionKeyDigitalPinMode@@if_ts_show_ign_key_switch
 		field = "Battery Input Divider Coefficient",	vbattDividerCoeff
 	dialog = alternator, "Alternator Settings",	yAxis
 		field = "Enabled",								isAlternatorControlEnabled