[FEATURE] Prearm

src/main/fc/fc_core.c

@@ -295,6 +295,16 @@ static void updateArmingStatus(void)
 	       DISABLE_ARMING_FLAG(ARMING_DISABLED_SERVO_AUTOTRIM);
 	    }
 
+        if (isModeActivationConditionPresent(BOXPREARM)) {
+            if (IS_RC_MODE_ACTIVE(BOXPREARM)) {
+                DISABLE_ARMING_FLAG(ARMING_DISABLED_NO_PREARM);
+            } else {
+                ENABLE_ARMING_FLAG(ARMING_DISABLED_NO_PREARM);
+            }
+        } else {
+            DISABLE_ARMING_FLAG(ARMING_DISABLED_NO_PREARM);
+        }
+
         /* CHECK: Arming switch */
         // If arming is disabled and the ARM switch is on
         // Note that this should be last check so all other blockers could be cleared correctly
@@ -506,6 +516,7 @@ void tryArm(void)
 #else
         beeper(BEEPER_ARMING);
 #endif
+
         statsOnArm();
 
         return;

src/main/fc/fc_msp_box.c

@@ -86,6 +86,7 @@ static const box_t boxes[CHECKBOX_ITEM_COUNT + 1] = {
     { BOXUSER2, "USER2", BOX_PERMANENT_ID_USER2 },
     { BOXLOITERDIRCHN, "LOITER CHANGE", 49 },
     { BOXMSPRCOVERRIDE, "MSP RC OVERRIDE", 50 },
+    { BOXPREARM, "PREARM", 51 },
     { CHECKBOX_ITEM_COUNT, NULL, 0xFF }
 };
 
@@ -163,6 +164,7 @@ void initActiveBoxIds(void)
 
     activeBoxIdCount = 0;
     activeBoxIds[activeBoxIdCount++] = BOXARM;
+    activeBoxIds[activeBoxIdCount++] = BOXPREARM;
 
     if (sensors(SENSOR_ACC) && STATE(ALTITUDE_CONTROL)) {
         activeBoxIds[activeBoxIdCount++] = BOXANGLE;

src/main/fc/rc_modes.c

@@ -134,13 +134,7 @@ void rcModeUpdate(boxBitmask_t *newState)
 
 bool isModeActivationConditionPresent(boxId_e modeId)
 {
-    for (int index = 0; index < MAX_MODE_ACTIVATION_CONDITION_COUNT; index++) {
-        if (modeActivationConditions(index)->modeId == modeId && IS_RANGE_USABLE(&modeActivationConditions(index)->range)) {
-            return true;
-        }
-    }
-
-    return false;
+    return specifiedConditionCountPerMode[modeId] > 0;
 }
 
 bool isRangeActive(uint8_t auxChannelIndex, const channelRange_t *range)

src/main/fc/rc_modes.h

@@ -68,6 +68,7 @@ typedef enum {
     BOXFPVANGLEMIX   = 39,
     BOXLOITERDIRCHN  = 40,
     BOXMSPRCOVERRIDE = 41,
+    BOXPREARM        = 42,
     CHECKBOX_ITEM_COUNT
 } boxId_e;
 

src/main/fc/runtime_config.c

@@ -36,7 +36,7 @@ const char *armingDisableFlagNames[]= {
     "FS", "ANGLE", "CAL", "OVRLD", "NAV", "COMPASS",
     "ACC", "ARMSW", "HWFAIL", "BOXFS", "KILLSW", "RX",
     "THR", "CLI", "CMS", "OSD", "ROLL/PITCH", "AUTOTRIM", "OOM",
-    "SETTINGFAIL", "PWMOUT"
+    "SETTINGFAIL", "PWMOUT", "NOPREARM"
 };
 #endif
 
@@ -57,7 +57,8 @@ const armingFlag_e armDisableReasonsChecklist[] = {
     ARMING_DISABLED_OSD_MENU,
     ARMING_DISABLED_ROLLPITCH_NOT_CENTERED,
     ARMING_DISABLED_SERVO_AUTOTRIM,
-    ARMING_DISABLED_OOM
+    ARMING_DISABLED_OOM,
+    ARMING_DISABLED_NO_PREARM
 };
 
 armingFlag_e isArmingDisabledReason(void)

src/main/fc/runtime_config.h

@@ -23,7 +23,6 @@ typedef enum {
     WAS_EVER_ARMED                                  = (1 << 3),
 
     ARMING_DISABLED_FAILSAFE_SYSTEM                 = (1 << 7),
-
     ARMING_DISABLED_NOT_LEVEL                       = (1 << 8),
     ARMING_DISABLED_SENSORS_CALIBRATING             = (1 << 9),
     ARMING_DISABLED_SYSTEM_OVERLOADED               = (1 << 10),
@@ -44,6 +43,7 @@ typedef enum {
     ARMING_DISABLED_OOM                             = (1 << 25),
     ARMING_DISABLED_INVALID_SETTING                 = (1 << 26),
     ARMING_DISABLED_PWM_OUTPUT_ERROR                = (1 << 27),
+    ARMING_DISABLED_NO_PREARM                       = (1 << 28),
 
     ARMING_DISABLED_ALL_FLAGS                       = (ARMING_DISABLED_FAILSAFE_SYSTEM | ARMING_DISABLED_NOT_LEVEL | ARMING_DISABLED_SENSORS_CALIBRATING | 
                                                        ARMING_DISABLED_SYSTEM_OVERLOADED | ARMING_DISABLED_NAVIGATION_UNSAFE |
@@ -52,7 +52,7 @@ typedef enum {
                                                        ARMING_DISABLED_BOXKILLSWITCH | ARMING_DISABLED_RC_LINK | ARMING_DISABLED_THROTTLE | ARMING_DISABLED_CLI |
                                                        ARMING_DISABLED_CMS_MENU | ARMING_DISABLED_OSD_MENU | ARMING_DISABLED_ROLLPITCH_NOT_CENTERED |
                                                        ARMING_DISABLED_SERVO_AUTOTRIM | ARMING_DISABLED_OOM | ARMING_DISABLED_INVALID_SETTING |
-                                                       ARMING_DISABLED_PWM_OUTPUT_ERROR),
+                                                       ARMING_DISABLED_PWM_OUTPUT_ERROR | ARMING_DISABLED_NO_PREARM),
 } armingFlag_e;
 
 // Arming blockers that can be overriden by emergency arming.
@@ -78,7 +78,7 @@ extern const char *armingDisableFlagNames[];
 #define ARMING_FLAG(mask)           (armingFlags & (mask))
 
 // Returns the 1st flag from ARMING_DISABLED_ALL_FLAGS which is
-// preventing arming, or zero is arming is not disabled.
+// preventing arming, or zero if arming is not disabled.
 armingFlag_e isArmingDisabledReason(void);
 
 typedef enum {

src/main/io/osd.c

@@ -712,6 +712,8 @@ static const char * osdArmingDisabledReasonMessage(void)
             return OSD_MESSAGE_STR(OSD_MSG_CLI_ACTIVE);
         case ARMING_DISABLED_PWM_OUTPUT_ERROR:
             return OSD_MESSAGE_STR(OSD_MSG_PWM_INIT_ERROR);
+        case ARMING_DISABLED_NO_PREARM:
+            return OSD_MESSAGE_STR(OSD_MSG_NO_PREARM);
             // Cases without message
         case ARMING_DISABLED_CMS_MENU:
             FALLTHROUGH;

src/main/io/osd.h

@@ -76,6 +76,7 @@
 #define OSD_MSG_INVALID_SETTING     "INVALID SETTING"
 #define OSD_MSG_CLI_ACTIVE          "CLI IS ACTIVE"
 #define OSD_MSG_PWM_INIT_ERROR      "PWM INIT ERROR"
+#define OSD_MSG_NO_PREARM           "NO PREARM"
 #define OSD_MSG_RTH_FS              "(RTH)"
 #define OSD_MSG_EMERG_LANDING_FS    "(EMERGENCY LANDING)"
 #define OSD_MSG_MOVE_EXIT_FS        "!MOVE STICKS TO EXIT FS!"

src/main/io/osd_dji_hd.c

@@ -500,6 +500,8 @@ static const char * osdArmingDisabledReasonMessage(void)
             return OSD_MESSAGE_STR("CLI");
         case ARMING_DISABLED_PWM_OUTPUT_ERROR:
             return OSD_MESSAGE_STR("PWM ERR");
+        case ARMING_DISABLED_NO_PREARM:
+            return OSD_MESSAGE_STR("NO PREARM");
             // Cases without message
         case ARMING_DISABLED_CMS_MENU:
             FALLTHROUGH;