Detach midrc (input) from servo center (output).

This fixes incorrect servo center position when midrc was not 1500.
Most likely only experienced by futaba plane or servo/tilt users.

src/main/config/config.c

@@ -197,6 +197,7 @@ void resetEscAndServoConfig(escAndServoConfig_t *escAndServoConfig)
     escAndServoConfig->minthrottle = 1150;
     escAndServoConfig->maxthrottle = 1850;
     escAndServoConfig->mincommand = 1000;
+    escAndServoConfig->servoCenterPulse = 1500;
 }
 
 void resetFlight3DConfig(flight3DConfig_t *flight3DConfig)

src/main/flight/mixer.c

@@ -473,14 +473,14 @@ static void airplaneMixer(void)
         int16_t lFlap = determineServoMiddleOrForwardFromChannel(2);
 
         lFlap = constrain(lFlap, servoConf[2].min, servoConf[2].max);
-        lFlap = rxConfig->midrc - lFlap;
+        lFlap = escAndServoConfig->servoCenterPulse - lFlap;
         if (slow_LFlaps < lFlap)
             slow_LFlaps += airplaneConfig->flaps_speed;
         else if (slow_LFlaps > lFlap)
             slow_LFlaps -= airplaneConfig->flaps_speed;
 
         servo[2] = ((int32_t)servoConf[2].rate * slow_LFlaps) / 100L;
-        servo[2] += rxConfig->midrc;
+        servo[2] += escAndServoConfig->servoCenterPulse;
     }
 
     if (FLIGHT_MODE(PASSTHRU_MODE)) {   // Direct passthru from RX

src/main/io/escservo.h

@@ -18,7 +18,10 @@
 #pragma once
 
 typedef struct escAndServoConfig_s {
+
+    // PWM values, in milliseconds, common range is 1000-2000 (1 to 2ms)
     uint16_t minthrottle;                   // Set the minimum throttle command sent to the ESC (Electronic Speed Controller). This is the minimum value that allow motors to run at a idle speed.
     uint16_t maxthrottle;                   // This is the maximum value for the ESCs at full power this value can be increased up to 2000
     uint16_t mincommand;                    // This is the value for the ESCs when they are not armed. In some cases, this value must be lowered down to 900 for some specific ESCs
+    uint16_t servoCenterPulse;              // This is the value for servos when they should be in the middle. e.g. 1500.
 } escAndServoConfig_t;

src/main/io/serial_cli.c

@@ -226,6 +226,7 @@ const clivalue_t valueTable[] = {
     { "min_throttle",               VAR_UINT16 | MASTER_VALUE,  &masterConfig.escAndServoConfig.minthrottle, PWM_RANGE_ZERO, PWM_RANGE_MAX },
     { "max_throttle",               VAR_UINT16 | MASTER_VALUE,  &masterConfig.escAndServoConfig.maxthrottle, PWM_RANGE_ZERO, PWM_RANGE_MAX },
     { "min_command",                VAR_UINT16 | MASTER_VALUE,  &masterConfig.escAndServoConfig.mincommand, PWM_RANGE_ZERO, PWM_RANGE_MAX },
+    { "servo_center_pulse",         VAR_UINT16 | MASTER_VALUE,  &masterConfig.escAndServoConfig.servoCenterPulse, PWM_RANGE_ZERO, PWM_RANGE_MAX },
 
     { "3d_deadband_low",            VAR_UINT16 | MASTER_VALUE,  &masterConfig.flight3DConfig.deadband3d_low, PWM_RANGE_ZERO, PWM_RANGE_MAX }, // FIXME upper limit should match code in the mixer, 1500 currently
     { "3d_deadband_high",           VAR_UINT16 | MASTER_VALUE,  &masterConfig.flight3DConfig.deadband3d_high, PWM_RANGE_ZERO, PWM_RANGE_MAX }, // FIXME lower limit should match code in the mixer, 1500 currently,

src/main/main.c

@@ -305,7 +305,7 @@ void init(void)
         pwm_params.idlePulse = masterConfig.flight3DConfig.neutral3d;
     if (pwm_params.motorPwmRate > 500)
         pwm_params.idlePulse = 0; // brushed motors
-    pwm_params.servoCenterPulse = masterConfig.rxConfig.midrc;
+    pwm_params.servoCenterPulse = masterConfig.escAndServoConfig.servoCenterPulse;
 
     pwmRxInit(masterConfig.inputFilteringMode);
 

src/main/rx/rx.h

@@ -68,11 +68,11 @@ typedef struct rxConfig_s {
     uint8_t rcmap[MAX_MAPPABLE_RX_INPUTS];  // mapping of radio channels to internal RPYTA+ order
     uint8_t serialrx_provider;              // type of UART-based receiver (0 = spek 10, 1 = spek 11, 2 = sbus). Must be enabled by FEATURE_RX_SERIAL first.
     uint8_t spektrum_sat_bind;              // number of bind pulses for Spektrum satellite receivers
+    uint8_t rssi_channel;
+    uint8_t rssi_scale;
     uint16_t midrc;                         // Some radios have not a neutral point centered on 1500. can be changed here
     uint16_t mincheck;                      // minimum rc end
     uint16_t maxcheck;                      // maximum rc end
-    uint8_t rssi_channel;
-    uint8_t rssi_scale;
 } rxConfig_t;
 
 #define REMAPPABLE_CHANNEL_COUNT (sizeof(((rxConfig_t *)0)->rcmap) / sizeof(((rxConfig_t *)0)->rcmap[0]))