diff --git a/src/main/fc/config.c b/src/main/fc/config.c
index 4b623a101..f23792f45 100644
--- a/src/main/fc/config.c
+++ b/src/main/fc/config.c
@@ -61,9 +61,7 @@
 #include "sensors/battery.h"
 #include "sensors/gyro.h"
 
-#ifndef USE_OSD_SLAVE
 pidProfile_t *currentPidProfile;
-#endif
 
 #ifndef RX_SPI_DEFAULT_PROTOCOL
 #define RX_SPI_DEFAULT_PROTOCOL 0
@@ -89,7 +87,6 @@ PG_RESET_TEMPLATE(systemConfig_t, systemConfig,
     .boardIdentifier = TARGET_BOARD_IDENTIFIER
 );
 
-#ifndef USE_OSD_SLAVE
 uint8_t getCurrentPidProfileIndex(void)
 {
     return systemConfig()->pidProfileIndex;
@@ -109,7 +106,6 @@ uint16_t getCurrentMinthrottle(void)
 {
     return motorConfig()->minthrottle;
 }
-#endif // USE_OSD_SLAVE
 
 void resetConfigs(void)
 {
@@ -122,7 +118,6 @@ void resetConfigs(void)
 
 static void activateConfig(void)
 {
-#ifndef USE_OSD_SLAVE
     loadPidProfile();
     loadControlRateProfile();
 
@@ -139,7 +134,6 @@ static void activateConfig(void)
     accInitFilters();
 
     imuConfigure(throttleCorrectionConfig()->throttle_correction_angle, throttleCorrectionConfig()->throttle_correction_value);
-#endif // USE_OSD_SLAVE
 
 #ifdef USE_LED_STRIP
     reevaluateLedConfig();
@@ -148,7 +142,7 @@ static void activateConfig(void)
 
 static void validateAndFixConfig(void)
 {
-#if !defined(USE_QUAD_MIXER_ONLY) && !defined(USE_OSD_SLAVE)
+#if !defined(USE_QUAD_MIXER_ONLY)
     // Reset unsupported mixer mode to default.
     // This check will be gone when motor/servo mixers are loaded dynamically
     // by configurator as a part of configuration procedure.
@@ -177,7 +171,6 @@ static void validateAndFixConfig(void)
         featureDisable(FEATURE_GPS);
     }
 
-#ifndef USE_OSD_SLAVE
     if (systemConfig()->activeRateProfile >= CONTROL_RATE_PROFILE_COUNT) {
         systemConfigMutable()->activeRateProfile = 0;
     }
@@ -304,7 +297,6 @@ static void validateAndFixConfig(void)
             removeModeActivationCondition(BOXGPSRESCUE);
         }
     }
-#endif // USE_OSD_SLAVE
 
 #if defined(USE_ESC_SENSOR)
     if (!findSerialPortConfig(FUNCTION_ESC_SENSOR)) {
@@ -409,7 +401,6 @@ static void validateAndFixConfig(void)
 #endif
 }
 
-#ifndef USE_OSD_SLAVE
 void validateAndFixGyroConfig(void)
 {
 #ifdef USE_GYRO_DATA_ANALYSE
@@ -511,13 +502,10 @@ void validateAndFixGyroConfig(void)
         }
     }
 }
-#endif // USE_OSD_SLAVE
 
 bool readEEPROM(void)
 {
-#ifndef USE_OSD_SLAVE
     suspendRxSignal();
-#endif
 
     // Sanity check, read flash
     bool success = loadEEPROM();
@@ -526,9 +514,7 @@ bool readEEPROM(void)
 
     activateConfig();
 
-#ifndef USE_OSD_SLAVE
     resumeRxSignal();
-#endif
 
     return success;
 }
@@ -537,15 +523,11 @@ void writeEEPROM(void)
 {
     validateAndFixConfig();
 
-#ifndef USE_OSD_SLAVE
     suspendRxSignal();
-#endif
 
     writeConfigToEEPROM();
 
-#ifndef USE_OSD_SLAVE
     resumeRxSignal();
-#endif
 }
 
 void writeEEPROMWithFeatures(uint32_t features)
@@ -580,7 +562,6 @@ void saveConfigAndNotify(void)
     beeperConfirmationBeeps(1);
 }
 
-#ifndef USE_OSD_SLAVE
 void changePidProfile(uint8_t pidProfileIndex)
 {
     if (pidProfileIndex < MAX_PROFILE_COUNT) {
@@ -590,4 +571,3 @@ void changePidProfile(uint8_t pidProfileIndex)
 
     beeperConfirmationBeeps(pidProfileIndex + 1);
 }
-#endif
diff --git a/src/main/fc/fc_hardfaults.c b/src/main/fc/fc_hardfaults.c
index e575c4a2e..c6f78289e 100644
--- a/src/main/fc/fc_hardfaults.c
+++ b/src/main/fc/fc_hardfaults.c
@@ -127,13 +127,11 @@ void HardFault_Handler(void)
 {
     LED2_ON;
 
-#ifndef USE_OSD_SLAVE
     // fall out of the sky
     uint8_t requiredStateForMotors = SYSTEM_STATE_CONFIG_LOADED | SYSTEM_STATE_MOTORS_READY;
     if ((systemState & requiredStateForMotors) == requiredStateForMotors) {
         stopMotors();
     }
-#endif
 
 #ifdef USE_TRANSPONDER
     // prevent IR LEDs from burning out.
diff --git a/src/main/fc/fc_init.c b/src/main/fc/fc_init.c
index 7b83feaea..6136711b2 100644
--- a/src/main/fc/fc_init.c
+++ b/src/main/fc/fc_init.c
@@ -551,11 +551,11 @@ void init(void)
     cmsInit();
 #endif
 
-#if (defined(USE_OSD) || (defined(USE_MSP_DISPLAYPORT) && defined(USE_CMS)) || defined(USE_OSD_SLAVE))
+#if (defined(USE_OSD) || (defined(USE_MSP_DISPLAYPORT) && defined(USE_CMS)))
     displayPort_t *osdDisplayPort = NULL;
 #endif
 
-#if defined(USE_OSD) && !defined(USE_OSD_SLAVE)
+#if defined(USE_OSD)
     //The OSD need to be initialised after GYRO to avoid GYRO initialisation failure on some targets
 
     if (featureIsEnabled(FEATURE_OSD)) {
@@ -570,15 +570,6 @@ void init(void)
     }
 #endif
 
-#if defined(USE_OSD_SLAVE) && !defined(USE_OSD)
-#if defined(USE_MAX7456)
-    // If there is a max7456 chip for the OSD then use it
-    osdDisplayPort = max7456DisplayPortInit(vcdProfile());
-    // osdInit  will register with CMS by itself.
-    osdSlaveInit(osdDisplayPort);
-#endif
-#endif
-
 #if defined(USE_CMS) && defined(USE_MSP_DISPLAYPORT)
     // If BFOSD is not active, then register MSP_DISPLAYPORT as a CMS device.
     if (!osdDisplayPort)
diff --git a/src/main/fc/fc_tasks.c b/src/main/fc/fc_tasks.c
index 8427ab146..90052d8bb 100644
--- a/src/main/fc/fc_tasks.c
+++ b/src/main/fc/fc_tasks.c
@@ -119,16 +119,6 @@ static void taskMain(timeUs_t currentTimeUs)
 #endif
 }
 
-#ifdef USE_OSD_SLAVE
-static bool taskSerialCheck(timeUs_t currentTimeUs, timeDelta_t currentDeltaTimeUs)
-{
-    UNUSED(currentTimeUs);
-    UNUSED(currentDeltaTimeUs);
-
-    return mspSerialWaiting();
-}
-#endif
-
 static void taskHandleSerial(timeUs_t currentTimeUs)
 {
     UNUSED(currentTimeUs);
@@ -145,11 +135,7 @@ static void taskHandleSerial(timeUs_t currentTimeUs)
         return;
     }
 #endif
-#ifndef OSD_SLAVE
     bool evaluateMspData = ARMING_FLAG(ARMED) ? MSP_SKIP_NON_MSP_DATA : MSP_EVALUATE_NON_MSP_DATA;
-#else
-    bool evaluateMspData = osdSlaveIsLocked ?  MSP_SKIP_NON_MSP_DATA : MSP_EVALUATE_NON_MSP_DATA;;
-#endif
     mspSerialProcess(evaluateMspData, mspFcProcessCommand, mspFcProcessReply);
 }
 
@@ -163,7 +149,6 @@ static void taskBatteryAlerts(timeUs_t currentTimeUs)
     batteryUpdateAlarms();
 }
 
-#ifndef USE_OSD_SLAVE
 static void taskUpdateAccelerometer(timeUs_t currentTimeUs)
 {
     accUpdate(currentTimeUs, &accelerometerConfigMutable()->accelerometerTrims);
@@ -190,7 +175,6 @@ static void taskUpdateRxMain(timeUs_t currentTimeUs)
     updateRcCommands();
     updateArmingStatus();
 }
-#endif
 
 #ifdef USE_BARO
 static void taskUpdateBaro(timeUs_t currentTimeUs)
@@ -248,11 +232,7 @@ void fcTasksInit(void)
     setTaskEnabled(TASK_BATTERY_VOLTAGE, useBatteryVoltage);
     const bool useBatteryCurrent = batteryConfig()->currentMeterSource != CURRENT_METER_NONE;
     setTaskEnabled(TASK_BATTERY_CURRENT, useBatteryCurrent);
-#ifdef USE_OSD_SLAVE
-    const bool useBatteryAlerts = batteryConfig()->useVBatAlerts || batteryConfig()->useConsumptionAlerts;
-#else
     const bool useBatteryAlerts = batteryConfig()->useVBatAlerts || batteryConfig()->useConsumptionAlerts || featureIsEnabled(FEATURE_OSD);
-#endif
     setTaskEnabled(TASK_BATTERY_ALERTS, (useBatteryVoltage || useBatteryCurrent) && useBatteryAlerts);
 
 #ifdef USE_TRANSPONDER
@@ -263,9 +243,6 @@ void fcTasksInit(void)
     setTaskEnabled(TASK_STACK_CHECK, true);
 #endif
 
-#ifdef USE_OSD_SLAVE
-    setTaskEnabled(TASK_OSD_SLAVE, osdSlaveInitialized());
-#else
     if (sensors(SENSOR_GYRO)) {
         rescheduleTask(TASK_GYROPID, gyro.targetLooptime);
         setTaskEnabled(TASK_GYROPID, true);
@@ -284,21 +261,27 @@ void fcTasksInit(void)
 #ifdef USE_BEEPER
     setTaskEnabled(TASK_BEEPER, true);
 #endif
+
 #ifdef USE_GPS
     setTaskEnabled(TASK_GPS, featureIsEnabled(FEATURE_GPS));
 #endif
+
 #ifdef USE_MAG
     setTaskEnabled(TASK_COMPASS, sensors(SENSOR_MAG));
 #endif
+
 #ifdef USE_BARO
     setTaskEnabled(TASK_BARO, sensors(SENSOR_BARO));
 #endif
+
 #if defined(USE_BARO) || defined(USE_GPS)
     setTaskEnabled(TASK_ALTITUDE, sensors(SENSOR_BARO) || featureIsEnabled(FEATURE_GPS));
 #endif
+
 #ifdef USE_DASHBOARD
     setTaskEnabled(TASK_DASHBOARD, featureIsEnabled(FEATURE_DASHBOARD));
 #endif
+
 #ifdef USE_TELEMETRY
     if (featureIsEnabled(FEATURE_TELEMETRY)) {
         setTaskEnabled(TASK_TELEMETRY, true);
@@ -311,27 +294,35 @@ void fcTasksInit(void)
         }
     }
 #endif
+
 #ifdef USE_LED_STRIP
     setTaskEnabled(TASK_LEDSTRIP, featureIsEnabled(FEATURE_LED_STRIP));
 #endif
+
 #ifdef USE_TRANSPONDER
     setTaskEnabled(TASK_TRANSPONDER, featureIsEnabled(FEATURE_TRANSPONDER));
 #endif
+
 #ifdef USE_OSD
     setTaskEnabled(TASK_OSD, featureIsEnabled(FEATURE_OSD) && osdInitialized());
 #endif
+
 #ifdef USE_BST
     setTaskEnabled(TASK_BST_MASTER_PROCESS, true);
 #endif
+
 #ifdef USE_ESC_SENSOR
     setTaskEnabled(TASK_ESC_SENSOR, featureIsEnabled(FEATURE_ESC_SENSOR));
 #endif
+
 #ifdef USE_ADC_INTERNAL
     setTaskEnabled(TASK_ADC_INTERNAL, true);
 #endif
+
 #ifdef USE_PINIOBOX
     setTaskEnabled(TASK_PINIOBOX, true);
 #endif
+
 #ifdef USE_CMS
 #ifdef USE_MSP_DISPLAYPORT
     setTaskEnabled(TASK_CMS, true);
@@ -339,18 +330,20 @@ void fcTasksInit(void)
     setTaskEnabled(TASK_CMS, featureIsEnabled(FEATURE_OSD) || featureIsEnabled(FEATURE_DASHBOARD));
 #endif
 #endif
+
 #ifdef USE_VTX_CONTROL
 #if defined(USE_VTX_RTC6705) || defined(USE_VTX_SMARTAUDIO) || defined(USE_VTX_TRAMP)
     setTaskEnabled(TASK_VTXCTRL, true);
 #endif
 #endif
+
 #ifdef USE_CAMERA_CONTROL
     setTaskEnabled(TASK_CAMCTRL, true);
 #endif
+
 #ifdef USE_RCDEVICE
     setTaskEnabled(TASK_RCDEVICE, rcdeviceIsEnabled());
 #endif
-#endif
 }
 
 cfTask_t cfTasks[TASK_COUNT] = {
@@ -373,14 +366,8 @@ cfTask_t cfTasks[TASK_COUNT] = {
     [TASK_SERIAL] = {
         .taskName = "SERIAL",
         .taskFunc = taskHandleSerial,
-#ifdef USE_OSD_SLAVE
-        .checkFunc = taskSerialCheck,
-        .desiredPeriod = TASK_PERIOD_HZ(100),
-        .staticPriority = TASK_PRIORITY_REALTIME,
-#else
         .desiredPeriod = TASK_PERIOD_HZ(100),       // 100 Hz should be enough to flush up to 115 bytes @ 115200 baud
         .staticPriority = TASK_PRIORITY_LOW,
-#endif
     },
 
     [TASK_BATTERY_ALERTS] = {
@@ -421,17 +408,6 @@ cfTask_t cfTasks[TASK_COUNT] = {
     },
 #endif
 
-#ifdef USE_OSD_SLAVE
-    [TASK_OSD_SLAVE] = {
-        .taskName = "OSD_SLAVE",
-        .checkFunc = osdSlaveCheck,
-        .taskFunc = osdSlaveUpdate,
-        .desiredPeriod = TASK_PERIOD_HZ(60),        // 60 Hz
-        .staticPriority = TASK_PRIORITY_HIGH,
-    },
-
-#else
-
     [TASK_GYROPID] = {
         .taskName = "PID",
         .subTaskName = "GYRO",
@@ -621,5 +597,4 @@ cfTask_t cfTasks[TASK_COUNT] = {
         .staticPriority = TASK_PRIORITY_IDLE
     },
 #endif
-#endif
 };
diff --git a/src/main/flight/pid.h b/src/main/flight/pid.h
index 3c78df75e..fb3444d83 100644
--- a/src/main/flight/pid.h
+++ b/src/main/flight/pid.h
@@ -147,9 +147,7 @@ typedef struct pidProfile_s {
     uint8_t abs_control_error_limit;        // Limit to the accumulated error
 } pidProfile_t;
 
-#ifndef USE_OSD_SLAVE
 PG_DECLARE_ARRAY(pidProfile_t, MAX_PROFILE_COUNT, pidProfiles);
-#endif
 
 typedef struct pidConfig_s {
     uint8_t pid_process_denom;              // Processing denominator for PID controller vs gyro sampling rate
diff --git a/src/main/interface/msp.c b/src/main/interface/msp.c
index a6a272a9a..f58272680 100644
--- a/src/main/interface/msp.c
+++ b/src/main/interface/msp.c
@@ -142,8 +142,6 @@ enum {
 
 static uint8_t rebootMode;
 
-#ifndef USE_OSD_SLAVE
-
 typedef enum {
     MSP_SDCARD_STATE_NOT_PRESENT = 0,
     MSP_SDCARD_STATE_FATAL       = 1,
@@ -162,7 +160,6 @@ typedef enum {
 } mspFlashFsFlags_e;
 
 #define RATEPROFILE_MASK (1 << 7)
-#endif //USE_OSD_SLAVE
 
 #define RTC_NOT_SUPPORTED 0xff
 
@@ -242,9 +239,7 @@ static void mspRebootFn(serialPort_t *serialPort)
 {
     UNUSED(serialPort);
 
-#ifndef USE_OSD_SLAVE
     stopPwmAllMotors();
-#endif
 
     switch (rebootMode) {
     case MSP_REBOOT_FIRMWARE:
@@ -270,7 +265,6 @@ static void mspRebootFn(serialPort_t *serialPort)
     while (true) ;
 }
 
-#ifndef USE_OSD_SLAVE
 static void serializeSDCardSummaryReply(sbuf_t *dst)
 {
 #ifdef USE_SDCARD
@@ -434,7 +428,6 @@ static void serializeDataflashReadReply(sbuf_t *dst, uint32_t address, const uin
     }
 }
 #endif // USE_FLASHFS
-#endif // USE_OSD_SLAVE
 
 /*
  * Returns true if the command was processd, false otherwise.
@@ -469,14 +462,10 @@ static bool mspCommonProcessOutCommand(uint8_t cmdMSP, sbuf_t *dst, mspPostProce
 #else
         sbufWriteU16(dst, 0); // No other build targets currently have hardware revision detection.
 #endif
-#ifdef USE_OSD_SLAVE
-        sbufWriteU8(dst, 1);  // 1 == OSD
-#else
 #if defined(USE_OSD) && defined(USE_MAX7456)
         sbufWriteU8(dst, 2);  // 2 == FC with OSD
 #else
         sbufWriteU8(dst, 0);  // 0 == FC
-#endif
 #endif
         // Board communication capabilities (uint8)
         // Bit 0: 1 iff the board has VCP
@@ -523,11 +512,7 @@ static bool mspCommonProcessOutCommand(uint8_t cmdMSP, sbuf_t *dst, mspPostProce
     case MSP_ANALOG:
         sbufWriteU8(dst, (uint8_t)constrain(getBatteryVoltage(), 0, 255));
         sbufWriteU16(dst, (uint16_t)constrain(getMAhDrawn(), 0, 0xFFFF)); // milliamp hours drawn from battery
-#ifdef USE_OSD_SLAVE
-        sbufWriteU16(dst, 0); // rssi
-#else
         sbufWriteU16(dst, getRssi());
-#endif
         sbufWriteU16(dst, (int16_t)constrain(getAmperage(), -0x8000, 0x7FFF)); // send current in 0.01 A steps, range is -320A to 320A
         break;
 
@@ -699,7 +684,7 @@ static bool mspCommonProcessOutCommand(uint8_t cmdMSP, sbuf_t *dst, mspPostProce
 
     case MSP_OSD_CONFIG: {
 #define OSD_FLAGS_OSD_FEATURE           (1 << 0)
-#define OSD_FLAGS_OSD_SLAVE             (1 << 1)
+//#define OSD_FLAGS_OSD_SLAVE             (1 << 1)
 #define OSD_FLAGS_RESERVED_1            (1 << 2)
 #define OSD_FLAGS_RESERVED_2            (1 << 3)
 #define OSD_FLAGS_OSD_HARDWARE_MAX_7456 (1 << 4)
@@ -708,9 +693,6 @@ static bool mspCommonProcessOutCommand(uint8_t cmdMSP, sbuf_t *dst, mspPostProce
 #if defined(USE_OSD)
         osdFlags |= OSD_FLAGS_OSD_FEATURE;
 #endif
-#if defined(USE_OSD_SLAVE)
-        osdFlags |= OSD_FLAGS_OSD_SLAVE;
-#endif
 #ifdef USE_MAX7456
         osdFlags |= OSD_FLAGS_OSD_HARDWARE_MAX_7456;
 #endif
@@ -769,38 +751,6 @@ static bool mspCommonProcessOutCommand(uint8_t cmdMSP, sbuf_t *dst, mspPostProce
     return true;
 }
 
-#ifdef USE_OSD_SLAVE
-static bool mspProcessOutCommand(uint8_t cmdMSP, sbuf_t *dst)
-{
-    switch (cmdMSP) {
-    case MSP_STATUS_EX:
-    case MSP_STATUS:
-        sbufWriteU16(dst, getTaskDeltaTime(TASK_SERIAL));
-#ifdef USE_I2C
-        sbufWriteU16(dst, i2cGetErrorCounter());
-#else
-        sbufWriteU16(dst, 0);
-#endif
-        sbufWriteU16(dst, 0); // sensors
-        sbufWriteU32(dst, 0); // flight modes
-        sbufWriteU8(dst, 0); // profile
-        sbufWriteU16(dst, constrain(averageSystemLoadPercent, 0, 100));
-        if (cmdMSP == MSP_STATUS_EX) {
-            sbufWriteU8(dst, 1); // max profiles
-            sbufWriteU8(dst, 0); // control rate profile
-        } else {
-            sbufWriteU16(dst, 0); // gyro cycle time
-        }
-        break;
-
-    default:
-        return false;
-    }
-    return true;
-}
-
-#else
-
 static bool mspProcessOutCommand(uint8_t cmdMSP, sbuf_t *dst)
 {
     bool unsupportedCommand = false;
@@ -1435,16 +1385,11 @@ static bool mspProcessOutCommand(uint8_t cmdMSP, sbuf_t *dst)
     }
     return !unsupportedCommand;
 }
-#endif // USE_OSD_SLAVE
 
 static mspResult_e mspFcProcessOutCommandWithArg(uint8_t cmdMSP, sbuf_t *src, sbuf_t *dst, mspPostProcessFnPtr *mspPostProcessFn)
 {
-#if defined(USE_OSD_SLAVE)
-        UNUSED(dst);
-#endif
 
     switch (cmdMSP) {
-#if !defined(USE_OSD_SLAVE)
     case MSP_BOXNAMES:
         {
             const int page = sbufBytesRemaining(src) ? sbufReadU8(src) : 0;
@@ -1457,7 +1402,6 @@ static mspResult_e mspFcProcessOutCommandWithArg(uint8_t cmdMSP, sbuf_t *src, sb
             serializeBoxReply(dst, page, &serializeBoxPermanentIdFn);
         }
         break;
-#endif
     case MSP_REBOOT:
         if (sbufBytesRemaining(src)) {
             rebootMode = sbufReadU8(src);
@@ -1555,34 +1499,6 @@ static void mspFcDataFlashReadCommand(sbuf_t *dst, sbuf_t *src)
 }
 #endif
 
-#ifdef USE_OSD_SLAVE
-static mspResult_e mspProcessInCommand(uint8_t cmdMSP, sbuf_t *src)
-{
-    UNUSED(cmdMSP);
-    UNUSED(src);
-
-    switch(cmdMSP) {
-    case MSP_RESET_CONF:
-        resetEEPROM();
-        readEEPROM();
-        break;
-    case MSP_EEPROM_WRITE:
-        if (featureMaskIsCopied) {
-            writeEEPROMWithFeatures(featureMaskCopy);
-        } else {
-            writeEEPROM();
-        }
-        readEEPROM();
-        break;
-    default:
-        // we do not know how to handle the (valid) message, indicate error MSP $M!
-        return MSP_RESULT_ERROR;
-    }
-    return MSP_RESULT_ACK;
-}
-
-#else
-
 static mspResult_e mspProcessInCommand(uint8_t cmdMSP, sbuf_t *src)
 {
     uint32_t i;
@@ -2403,7 +2319,6 @@ static mspResult_e mspProcessInCommand(uint8_t cmdMSP, sbuf_t *src)
     }
     return MSP_RESULT_ACK;
 }
-#endif // USE_OSD_SLAVE
 
 static mspResult_e mspCommonProcessInCommand(uint8_t cmdMSP, sbuf_t *src, mspPostProcessFnPtr *mspPostProcessFn)
 {
@@ -2507,7 +2422,7 @@ static mspResult_e mspCommonProcessInCommand(uint8_t cmdMSP, sbuf_t *src, mspPos
         batteryConfigMutable()->currentMeterSource = sbufReadU8(src);
         break;
 
-#if defined(USE_OSD) || defined (USE_OSD_SLAVE)
+#if defined(USE_OSD)
     case MSP_SET_OSD_CONFIG:
         {
             const uint8_t addr = sbufReadU8(src);
@@ -2581,7 +2496,7 @@ static mspResult_e mspCommonProcessInCommand(uint8_t cmdMSP, sbuf_t *src, mspPos
 #else
         return MSP_RESULT_ERROR;
 #endif
-#endif // OSD || USE_OSD_SLAVE
+#endif // OSD
 
     default:
         return mspProcessInCommand(cmdMSP, src);
@@ -2630,7 +2545,6 @@ void mspFcProcessReply(mspPacket_t *reply)
     UNUSED(src); // potentially unused depending on compile options.
 
     switch (reply->cmd) {
-#ifndef OSD_SLAVE
     case MSP_ANALOG:
         {
             uint8_t batteryVoltage = sbufReadU8(src);
@@ -2648,50 +2562,10 @@ void mspFcProcessReply(mspPacket_t *reply)
 #endif
         }
         break;
-#endif
-
-#ifdef USE_OSD_SLAVE
-    case MSP_DISPLAYPORT:
-        {
-            osdSlaveIsLocked = true; // lock it as soon as a MSP_DISPLAYPORT message is received to prevent accidental CLI/DFU mode.
-
-            const int subCmd = sbufReadU8(src);
-
-            switch (subCmd) {
-            case 0: // HEARTBEAT
-                osdSlaveHeartbeat();
-                break;
-            case 1: // RELEASE
-                break;
-            case 2: // CLEAR
-                osdSlaveClearScreen();
-                break;
-            case 3:
-                {
-#define MSP_OSD_MAX_STRING_LENGTH 30 // FIXME move this
-                    const uint8_t y = sbufReadU8(src); // row
-                    const uint8_t x = sbufReadU8(src); // column
-                    sbufReadU8(src); // reserved
-                    char buf[MSP_OSD_MAX_STRING_LENGTH + 1];
-                    const int len = MIN(sbufBytesRemaining(src), MSP_OSD_MAX_STRING_LENGTH);
-                    sbufReadData(src, &buf, len);
-                    buf[len] = 0;
-                    osdSlaveWrite(x, y, buf);
-                }
-                break;
-            case 4:
-                osdSlaveDrawScreen();
-                break;
-            }
-        }
-        break;
-#endif
     }
 }
 
 void mspInit(void)
 {
-#ifndef USE_OSD_SLAVE
     initActiveBoxIds();
-#endif
 }
diff --git a/src/main/interface/msp_box.c b/src/main/interface/msp_box.c
index ea1d5c9c5..fa03a3111 100644
--- a/src/main/interface/msp_box.c
+++ b/src/main/interface/msp_box.c
@@ -44,7 +44,6 @@
 #include "pg/piniobox.h"
 
 
-#ifndef USE_OSD_SLAVE
 // permanent IDs must uniquely identify BOX meaning, DO NOT REUSE THEM!
 static const box_t boxes[CHECKBOX_ITEM_COUNT] = {
     { BOXARM, "ARM", 0 },
@@ -343,4 +342,3 @@ int packFlightModeFlags(boxBitmask_t *mspFlightModeFlags)
     // return count of used bits
     return mspBoxIdx;
 }
-#endif // USE_OSD_SLAVE
diff --git a/src/main/io/displayport_max7456.c b/src/main/io/displayport_max7456.c
index ba0288a76..e076a7c82 100644
--- a/src/main/io/displayport_max7456.c
+++ b/src/main/io/displayport_max7456.c
@@ -166,11 +166,7 @@ static const displayPortVTable_t max7456VTable = {
 displayPort_t *max7456DisplayPortInit(const vcdProfile_t *vcdProfile)
 {
     if (
-#ifdef USE_OSD_SLAVE
-        !max7456Init(max7456Config(), vcdProfile, false)
-#else
         !max7456Init(max7456Config(), vcdProfile, systemConfig()->cpu_overclock)
-#endif
     ) {
         return NULL;
     }
diff --git a/src/main/scheduler/scheduler.h b/src/main/scheduler/scheduler.h
index a94c0fc85..477d7cd6b 100644
--- a/src/main/scheduler/scheduler.h
+++ b/src/main/scheduler/scheduler.h
@@ -104,9 +104,6 @@ typedef enum {
 #ifdef USE_OSD
     TASK_OSD,
 #endif
-#ifdef USE_OSD_SLAVE
-    TASK_OSD_SLAVE,
-#endif
 #ifdef USE_BST
     TASK_BST_MASTER_PROCESS,
 #endif