Copter: initial creation of motor_interlock

ArduCopter/AP_State.pde

@@ -139,3 +139,10 @@ void set_pre_arm_rc_check(bool b)
     }
 }
 
+void set_motor_interlock(bool b)
+{
+    if(ap.motor_interlock != b) {
+        ap.motor_interlock = b;
+    }
+}
+

ArduCopter/ArduCopter.pde

@@ -357,6 +357,7 @@ static union {
         uint8_t system_time_set     : 1; // 28      // true if the system time has been set from the GPS
         uint8_t gps_base_pos_set    : 1; // 29      // true when the gps base position has been set (used for RTK gps only)
         enum HomeState home_state   : 2; // 30,31   // home status (unset, set, locked)
+        uint8_t motor_interlock     : 1; // 32      // motor interlock status, final control for motors on/off
     };
     uint32_t value;
 } ap;

ArduCopter/defines.h

@@ -66,6 +66,7 @@ enum aux_sw_func {
     AUXSW_RELAY,                   // Relay pin on/off (only supports first relay)
     AUXSW_LANDING_GEAR,            // Landing gear controller
     AUXSW_LOST_COPTER_SOUND,       // Play lost copter sound
+    AUXSW_MOTOR_INTERLOCK,         // Motor On/Off switch
 };
 
 // Frame types

ArduCopter/motors.pde

@@ -686,6 +686,10 @@ static void init_disarm_motors()
     gcs_send_text_P(SEVERITY_HIGH, PSTR("DISARMING MOTORS"));
 #endif
 
+    // always force Motor Interlock to false
+    set_motor_interlock(false);
+
+    // send disarm command to motors
     motors.armed(false);
 
     // save compass offsets learned by the EKF

ArduCopter/switches.pde

@@ -545,6 +545,13 @@ static void do_aux_switch_function(int8_t ch_function, uint8_t ch_flag)
                 break;
         }
         break;
+
+    case AUXSW_MOTOR_INTERLOCK:
+        // Turn on when above LOW, because channel will also be used for speed
+        // control signal in tradheli
+        set_motor_interlock(ch_flag == AUX_SWITCH_HIGH || ch_flag == AUX_SWITCH_MIDDLE);
+        break;
+                
     }
 }