diff --git a/Makefile b/Makefile
index 2ab2c34f09..8350e13854 100644
--- a/Makefile
+++ b/Makefile
@@ -760,6 +760,7 @@ COMMON_SRC = \
             io/gps.c \
             io/ledstrip.c \
             io/osd.c \
+            io/osd_slave.c \
             io/transponder_ir.c \
             sensors/sonar.c \
             sensors/barometer.c \
@@ -851,6 +852,7 @@ SPEED_OPTIMISED_SRC := $(SPEED_OPTIMISED_SRC) \
             io/dashboard.c \
             io/displayport_max7456.c \
             io/osd.c \
+            io/osd_slave.c
 
 SIZE_OPTIMISED_SRC := $(SIZE_OPTIMISED_SRC) \
             drivers/serial_escserial.c \
diff --git a/src/main/config/parameter_group_ids.h b/src/main/config/parameter_group_ids.h
index f4b4ad4577..f497cf1cab 100644
--- a/src/main/config/parameter_group_ids.h
+++ b/src/main/config/parameter_group_ids.h
@@ -112,6 +112,7 @@
 #define PG_OSD_VIDEO_CONFIG 2046
 #define PG_OSD_ELEMENT_CONFIG 2045
 
+
 // 4095 is currently the highest number that can be used for a PGN due to the top 4 bits of the 16 bit value being reserved for the version when the PG is stored in an EEPROM.
 #define PG_RESERVED_FOR_TESTING_1 4095
 #define PG_RESERVED_FOR_TESTING_2 4094
diff --git a/src/main/drivers/max7456.c b/src/main/drivers/max7456.c
old mode 100755
new mode 100644
index 032ffc1814..fddb404ac7
--- a/src/main/drivers/max7456.c
+++ b/src/main/drivers/max7456.c
@@ -389,6 +389,8 @@ void max7456ReInit(void)
 
 void max7456Init(const vcdProfile_t *pVcdProfile)
 {
+    max7456HardwareReset();
+
 #ifdef MAX7456_SPI_CS_PIN
     max7456CsPin = IOGetByTag(IO_TAG(MAX7456_SPI_CS_PIN));
 #endif
@@ -612,4 +614,25 @@ void max7456WriteNvm(uint8_t char_address, const uint8_t *font_data)
     max7456Lock = false;
 }
 
+#ifdef MAX7456_NRST_PIN
+static IO_t max7456ResetPin        = IO_NONE;
+#endif
+
+void max7456HardwareReset(void)
+{
+#ifdef MAX7456_NRST_PIN
+#define IO_RESET_CFG      IO_CONFIG(GPIO_Mode_OUT, GPIO_Speed_2MHz, GPIO_OType_PP, GPIO_PuPd_DOWN)
+
+    max7456ResetPin = IOGetByTag(IO_TAG(MAX7456_NRST_PIN));
+    IOInit(max7456ResetPin, OWNER_OSD, 0);
+    IOConfigGPIO(max7456ResetPin, IO_RESET_CFG);
+
+
+    // RESET
+    IOLo(max7456ResetPin);
+    delay(100);
+    IOHi(max7456ResetPin);
+#endif
+}
+
 #endif
diff --git a/src/main/drivers/max7456.h b/src/main/drivers/max7456.h
index 3b7eb066b9..9dbed4ccb5 100755
--- a/src/main/drivers/max7456.h
+++ b/src/main/drivers/max7456.h
@@ -35,6 +35,7 @@
 extern uint16_t maxScreenSize;
 
 struct vcdProfile_s;
+void    max7456HardwareReset(void);
 void    max7456Init(const struct vcdProfile_s *vcdProfile);
 void    max7456DrawScreen(void);
 void    max7456WriteNvm(uint8_t char_address, const uint8_t *font_data);
diff --git a/src/main/fc/fc_init.c b/src/main/fc/fc_init.c
index 8c76f38683..0baea1564c 100644
--- a/src/main/fc/fc_init.c
+++ b/src/main/fc/fc_init.c
@@ -91,6 +91,7 @@
 #include "io/asyncfatfs/asyncfatfs.h"
 #include "io/transponder_ir.h"
 #include "io/osd.h"
+#include "io/osd_slave.h"
 #include "io/displayport_msp.h"
 #include "io/vtx.h"
 #include "io/vtx_smartaudio.h"
@@ -155,6 +156,21 @@ void processLoopback(void)
 #endif
 }
 
+
+#ifdef BUS_SWITCH_PIN
+void busSwitchInit(void)
+{
+static IO_t busSwitchResetPin        = IO_NONE;
+
+    busSwitchResetPin = IOGetByTag(IO_TAG(BUS_SWITCH_PIN));
+    IOInit(busSwitchResetPin, OWNER_SYSTEM, 0);
+    IOConfigGPIO(busSwitchResetPin, IOCFG_OUT_PP);
+
+    // ENABLE
+    IOLo(busSwitchResetPin);
+}
+#endif
+
 void init(void)
 {
 #ifdef USE_HAL_DRIVER
@@ -255,6 +271,10 @@ void init(void)
 
     timerInit();  // timer must be initialized before any channel is allocated
 
+#ifdef BUS_SWITCH_PIN
+    busSwitchInit();
+#endif
+
 #if defined(AVOID_UART1_FOR_PWM_PPM)
     serialInit(feature(FEATURE_SOFTSERIAL),
             feature(FEATURE_RX_PPM) || feature(FEATURE_RX_PARALLEL_PWM) ? SERIAL_PORT_USART1 : SERIAL_PORT_NONE);
@@ -440,11 +460,11 @@ void init(void)
     cmsInit();
 #endif
 
-#if ( defined(OSD) || (defined(USE_MSP_DISPLAYPORT) && defined(CMS)) )
+#if (defined(OSD) || (defined(USE_MSP_DISPLAYPORT) && defined(CMS)) || defined(USE_OSD_SLAVE))
     displayPort_t *osdDisplayPort = NULL;
 #endif
 
-#ifdef OSD
+#if defined(OSD) && !defined(USE_OSD_SLAVE)
     //The OSD need to be initialised after GYRO to avoid GYRO initialisation failure on some targets
 
     if (feature(FEATURE_OSD)) {
@@ -459,6 +479,15 @@ void init(void)
     }
 #endif
 
+#if defined(USE_OSD_SLAVE) && !defined(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(CMS) && defined(USE_MSP_DISPLAYPORT)
     // If BFOSD is not active, then register MSP_DISPLAYPORT as a CMS device.
     if (!osdDisplayPort)
@@ -588,6 +617,10 @@ void init(void)
     latchActiveFeatures();
     motorControlEnable = true;
 
+#ifdef USE_OSD_SLAVE
+    osdSlaveTasksInit();
+#else
     fcTasksInit();
+#endif
     systemState |= SYSTEM_STATE_READY;
 }
diff --git a/src/main/fc/fc_msp.c b/src/main/fc/fc_msp.c
index ddbcb2b4b7..67f7ea802b 100755
--- a/src/main/fc/fc_msp.c
+++ b/src/main/fc/fc_msp.c
@@ -78,6 +78,7 @@
 #include "io/ledstrip.h"
 #include "io/motors.h"
 #include "io/osd.h"
+#include "io/osd_slave.h"
 #include "io/serial.h"
 #include "io/serial_4way.h"
 #include "io/servos.h"
@@ -2010,6 +2011,57 @@ mspResult_e mspFcProcessCommand(mspPacket_t *cmd, mspPacket_t *reply, mspPostPro
     return ret;
 }
 
+void mspFcProcessReply(mspPacket_t *reply)
+{
+    sbuf_t *src = &reply->buf;
+    UNUSED(src); // potentially unused depending on compile options.
+
+    switch (reply->cmd) {
+        case MSP_DISPLAYPORT: {
+#ifdef USE_OSD_SLAVE
+            int subCmd = sbufReadU8(src);
+
+            switch (subCmd) {
+                case 0: // HEARTBEAT
+                    //debug[0]++;
+                    osdSlaveHeartbeat();
+                    break;
+                case 1: // RELEASE
+                    //debug[1]++;
+                    break;
+                case 2: // CLEAR
+                    //debug[2]++;
+                    osdSlaveClearScreen();
+                    break;
+                case 3: {
+                    //debug[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
+                    const uint8_t reserved = sbufReadU8(src);
+                    UNUSED(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();
+                }
+            }
+#endif
+            break;
+        }
+    }
+}
+
 /*
  * Return a pointer to the process command function
  */
diff --git a/src/main/fc/fc_msp.h b/src/main/fc/fc_msp.h
index f25e02fc11..7992a9f15c 100644
--- a/src/main/fc/fc_msp.h
+++ b/src/main/fc/fc_msp.h
@@ -31,3 +31,4 @@ const box_t *findBoxByPermanentId(uint8_t permenantId);
 
 void mspFcInit(void);
 mspResult_e mspFcProcessCommand(mspPacket_t *cmd, mspPacket_t *reply, mspPostProcessFnPtr *mspPostProcessFn);
+void mspFcProcessReply(mspPacket_t *reply);
diff --git a/src/main/fc/fc_tasks.c b/src/main/fc/fc_tasks.c
index 72c57be184..1dcb60b40c 100644
--- a/src/main/fc/fc_tasks.c
+++ b/src/main/fc/fc_tasks.c
@@ -59,6 +59,7 @@
 #include "io/gps.h"
 #include "io/ledstrip.h"
 #include "io/osd.h"
+#include "io/osd_slave.h"
 #include "io/serial.h"
 #include "io/transponder_ir.h"
 #include "io/vtx_tramp.h" // Will be gone
@@ -96,6 +97,13 @@ static void taskUpdateAccelerometer(timeUs_t currentTimeUs)
     accUpdate(&accelerometerConfigMutable()->accelerometerTrims);
 }
 
+bool taskSerialCheck(timeUs_t currentTimeUs, timeDelta_t currentDeltaTimeUs) {
+    UNUSED(currentTimeUs);
+    UNUSED(currentDeltaTimeUs);
+
+    return mspSerialWaiting();
+}
+
 static void taskHandleSerial(timeUs_t currentTimeUs)
 {
     UNUSED(currentTimeUs);
@@ -106,7 +114,11 @@ static void taskHandleSerial(timeUs_t currentTimeUs)
         return;
     }
 #endif
-    mspSerialProcess(ARMING_FLAG(ARMED) ? MSP_SKIP_NON_MSP_DATA : MSP_EVALUATE_NON_MSP_DATA, mspFcProcessCommand);
+#ifdef USE_OSD_SLAVE
+    mspSerialProcess(MSP_SKIP_NON_MSP_DATA, mspFcProcessCommand, mspFcProcessReply);
+#else
+    mspSerialProcess(ARMING_FLAG(ARMED) ? MSP_SKIP_NON_MSP_DATA : MSP_EVALUATE_NON_MSP_DATA, mspFcProcessCommand, mspFcProcessReply);
+#endif
 }
 
 void taskBatteryAlerts(timeUs_t currentTimeUs)
@@ -208,6 +220,32 @@ void taskVtxControl(uint32_t currentTime)
 }
 #endif
 
+#ifdef USE_OSD_SLAVE
+void osdSlaveTasksInit(void)
+{
+    schedulerInit();
+    setTaskEnabled(TASK_SERIAL, true);
+
+    bool useBatteryVoltage = batteryConfig()->voltageMeterSource != VOLTAGE_METER_NONE;
+    setTaskEnabled(TASK_BATTERY_VOLTAGE, useBatteryVoltage);
+    bool useBatteryCurrent = batteryConfig()->currentMeterSource != CURRENT_METER_NONE;
+    setTaskEnabled(TASK_BATTERY_CURRENT, useBatteryCurrent);
+
+    bool useBatteryAlerts = (batteryConfig()->useVBatAlerts || batteryConfig()->useConsumptionAlerts);
+    setTaskEnabled(TASK_BATTERY_ALERTS, (useBatteryVoltage || useBatteryCurrent) && useBatteryAlerts);
+
+#ifdef TRANSPONDER
+    setTaskEnabled(TASK_TRANSPONDER, feature(FEATURE_TRANSPONDER));
+#endif
+
+    setTaskEnabled(TASK_OSD_SLAVE, true);
+
+#ifdef STACK_CHECK
+    setTaskEnabled(TASK_STACK_CHECK, true);
+#endif
+}
+#endif
+
 void fcTasksInit(void)
 {
     schedulerInit();
@@ -281,6 +319,9 @@ void fcTasksInit(void)
 #ifdef OSD
     setTaskEnabled(TASK_OSD, feature(FEATURE_OSD));
 #endif
+#ifdef USE_OSD_SLAVE
+    setTaskEnabled(TASK_OSD_SLAVE, true);
+#endif
 #ifdef USE_BST
     setTaskEnabled(TASK_BST_MASTER_PROCESS, true);
 #endif
@@ -348,8 +389,14 @@ 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_DISPATCH] = {
@@ -457,6 +504,15 @@ cfTask_t cfTasks[TASK_COUNT] = {
         .staticPriority = TASK_PRIORITY_LOW,
     },
 #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,
+    },
+#endif
 #ifdef TELEMETRY
     [TASK_TELEMETRY] = {
         .taskName = "TELEMETRY",
diff --git a/src/main/fc/fc_tasks.h b/src/main/fc/fc_tasks.h
index 16db100bb6..5abc2b26d1 100644
--- a/src/main/fc/fc_tasks.h
+++ b/src/main/fc/fc_tasks.h
@@ -20,3 +20,4 @@
 #define LOOPTIME_SUSPEND_TIME 3  // Prevent too long busy wait times
 
 void fcTasksInit(void);
+void osdSlaveTasksInit(void);
diff --git a/src/main/io/displayport_max7456.c b/src/main/io/displayport_max7456.c
index e1a83fd67e..65f1464baf 100644
--- a/src/main/io/displayport_max7456.c
+++ b/src/main/io/displayport_max7456.c
@@ -33,6 +33,7 @@
 
 #include "io/displayport_max7456.h"
 #include "io/osd.h"
+#include "io/osd_slave.h"
 
 displayPort_t max7456DisplayPort;
 
@@ -41,9 +42,12 @@ PG_REGISTER(displayPortProfile_t, displayPortProfileMax7456, PG_DISPLAY_PORT_MAX
 
 static int grab(displayPort_t *displayPort)
 {
+    // FIXME this should probably not have a dependency on the OSD or OSD slave code
     UNUSED(displayPort);
+#ifdef OSD
     osdResetAlarms();
     refreshTimeout = 0;
+#endif
 
     return 0;
 }
diff --git a/src/main/io/displayport_msp.c b/src/main/io/displayport_msp.c
index 9c5d00fc46..b8b1a72847 100644
--- a/src/main/io/displayport_msp.c
+++ b/src/main/io/displayport_msp.c
@@ -79,8 +79,8 @@ static int clearScreen(displayPort_t *displayPort)
 
 static int drawScreen(displayPort_t *displayPort)
 {
-    UNUSED(displayPort);
-    return 0;
+    const uint8_t subcmd[] = { 4 };
+    return output(displayPort, MSP_DISPLAYPORT, subcmd, sizeof(subcmd));
 }
 
 static int screenSize(const displayPort_t *displayPort)
@@ -90,7 +90,7 @@ static int screenSize(const displayPort_t *displayPort)
 
 static int write(displayPort_t *displayPort, uint8_t col, uint8_t row, const char *string)
 {
-#define MSP_OSD_MAX_STRING_LENGTH 30
+#define MSP_OSD_MAX_STRING_LENGTH 30 // FIXME move this
     uint8_t buf[MSP_OSD_MAX_STRING_LENGTH + 4];
 
     int len = strlen(string);
diff --git a/src/main/io/osd_slave.c b/src/main/io/osd_slave.c
new file mode 100644
index 0000000000..5898e4c9ec
--- /dev/null
+++ b/src/main/io/osd_slave.c
@@ -0,0 +1,153 @@
+/*
+ * This file is part of Cleanflight.
+ *
+ * Cleanflight is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * Cleanflight is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with Cleanflight.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+/*
+ Created by Dominic Clifton
+  */
+
+#include <stdbool.h>
+#include <stdint.h>
+
+#include "platform.h"
+
+#ifdef USE_OSD_SLAVE
+
+#include "build/debug.h"
+#include "build/version.h"
+
+#include "common/printf.h"
+#include "common/utils.h"
+
+#include "drivers/max7456_symbols.h"
+#include "drivers/display.h"
+#include "drivers/system.h"
+
+#include "io/osd_slave.h"
+
+//#define OSD_SLAVE_DEBUG
+
+static displayPort_t *osdDisplayPort;
+
+static void osdDrawLogo(int x, int y)
+{
+    char fontOffset = 160;
+    for (int row = 0; row < 4; row++) {
+        for (int column = 0; column < 24; column++) {
+            if (fontOffset != 255) // FIXME magic number
+                displayWriteChar(osdDisplayPort, x + column, y + row, fontOffset++);
+        }
+    }
+}
+
+bool displayDrawScreenQueued = false;
+bool receivingScreen = false;
+bool stalled = false;
+
+void osdSlaveDrawScreen(void)
+{
+    displayDrawScreenQueued = true;
+}
+
+static uint32_t timeoutAt = 0;
+
+void osdSlaveClearScreen(void)
+{
+    displayClearScreen(osdDisplayPort);
+    receivingScreen = true;
+}
+
+void osdSlaveWriteChar(const uint8_t x, const uint8_t y, const uint8_t c)
+{
+    displayWriteChar(osdDisplayPort, x, y, c);
+}
+
+void osdSlaveWrite(const uint8_t x, const uint8_t y, const char *s)
+{
+    displayWrite(osdDisplayPort, x, y, s);
+}
+
+void osdSlaveHeartbeat(void)
+{
+    timeoutAt = micros() + (1000 * 1000);
+    stalled = false;
+}
+
+void osdSlaveInit(displayPort_t *osdDisplayPortToUse)
+{
+    if (!osdDisplayPortToUse)
+        return;
+
+    osdDisplayPort = osdDisplayPortToUse;
+
+    displayClearScreen(osdDisplayPort);
+
+    osdDrawLogo(3, 1);
+
+    char string_buffer[30];
+    sprintf(string_buffer, "V%s", FC_VERSION_STRING);
+    displayWrite(osdDisplayPort, 20, 6, string_buffer);
+    displayWrite(osdDisplayPort, 13, 6, "OSD");
+
+    displayResync(osdDisplayPort);
+
+    displayDrawScreenQueued = true;
+}
+
+bool osdSlaveCheck(timeUs_t currentTimeUs, timeDelta_t currentDeltaTimeUs)
+{
+    UNUSED(currentTimeUs);
+    UNUSED(currentDeltaTimeUs);
+
+    if (!stalled && (cmp32(currentTimeUs, timeoutAt) > 0)) {
+        stalled = true;
+
+        displayWrite(osdDisplayPort, 8, 12, "WAITING FOR FC");
+        displayResync(osdDisplayPort);
+    }
+
+    return receivingScreen || displayDrawScreenQueued || stalled;
+}
+
+/*
+ * Called periodically by the scheduler
+ */
+void osdSlaveUpdate(timeUs_t currentTimeUs)
+{
+    UNUSED(currentTimeUs);
+
+#ifdef MAX7456_DMA_CHANNEL_TX
+    // don't touch buffers if DMA transaction is in progress
+    if (displayIsTransferInProgress(osdDisplayPort)) {
+        return;
+    }
+#endif // MAX7456_DMA_CHANNEL_TX
+
+#ifdef OSD_SLAVE_DEBUG
+    char buff[32];
+    for (int i = 0; i < 4; i ++) {
+        sprintf(buff, "%5d", debug[i]);
+        displayWrite(osdDisplayPort, i * 8, 0, buff);
+    }
+#endif
+
+    if (displayDrawScreenQueued || stalled) {
+        displayDrawScreen(osdDisplayPort);
+        displayDrawScreenQueued = false;
+        receivingScreen = false;
+    }
+}
+#endif // OSD_SLAVE
diff --git a/src/main/io/osd_slave.h b/src/main/io/osd_slave.h
new file mode 100644
index 0000000000..c7974f84dc
--- /dev/null
+++ b/src/main/io/osd_slave.h
@@ -0,0 +1,40 @@
+/*
+ * This file is part of Cleanflight.
+ *
+ * Cleanflight is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * Cleanflight is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with Cleanflight.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#pragma once
+
+#ifdef USE_OSD_SLAVE
+#include "common/time.h"
+
+struct displayPort_s;
+
+// init
+void osdSlaveInit(struct displayPort_s *osdDisplayPort);
+
+// task api
+bool osdSlaveCheck(timeUs_t currentTimeUs, timeDelta_t currentDeltaTimeUs);
+void osdSlaveUpdate(timeUs_t currentTimeUs);
+
+// msp api
+void osdSlaveHeartbeat(void);
+void osdSlaveClearScreen(void);
+void osdSlaveWriteChar(const uint8_t x, const uint8_t y, const uint8_t c);
+void osdSlaveWrite(const uint8_t x, const uint8_t y, const char *s);
+
+void osdSlaveDrawScreen(void);
+
+#endif
diff --git a/src/main/msp/msp.h b/src/main/msp/msp.h
index b322ee7df6..5e6a14ac58 100644
--- a/src/main/msp/msp.h
+++ b/src/main/msp/msp.h
@@ -35,3 +35,4 @@ typedef struct mspPacket_s {
 struct serialPort_s;
 typedef void (*mspPostProcessFnPtr)(struct serialPort_s *port); // msp post process function, used for gracefully handling reboots, etc.
 typedef mspResult_e (*mspProcessCommandFnPtr)(mspPacket_t *cmd, mspPacket_t *reply, mspPostProcessFnPtr *mspPostProcessFn);
+typedef void (*mspProcessReplyFnPtr)(mspPacket_t *cmd);
diff --git a/src/main/msp/msp_serial.c b/src/main/msp/msp_serial.c
index 74f34fd95e..c1f2ece980 100644
--- a/src/main/msp/msp_serial.c
+++ b/src/main/msp/msp_serial.c
@@ -23,6 +23,7 @@
 
 #include "common/streambuf.h"
 #include "common/utils.h"
+#include "build/debug.h"
 
 #include "io/serial.h"
 
@@ -82,7 +83,19 @@ static bool mspSerialProcessReceivedData(mspPort_t *mspPort, uint8_t c)
     } else if (mspPort->c_state == MSP_HEADER_START) {
         mspPort->c_state = (c == 'M') ? MSP_HEADER_M : MSP_IDLE;
     } else if (mspPort->c_state == MSP_HEADER_M) {
-        mspPort->c_state = (c == '<') ? MSP_HEADER_ARROW : MSP_IDLE;
+        mspPort->c_state = MSP_IDLE;
+        switch(c) {
+            case '<': // COMMAND
+                mspPort->packetType = MSP_PACKET_COMMAND;
+                mspPort->c_state = MSP_HEADER_ARROW;
+                break;
+            case '>': // REPLY
+                mspPort->packetType = MSP_PACKET_REPLY;
+                mspPort->c_state = MSP_HEADER_ARROW;
+                break;
+            default:
+                break;
+        }
     } else if (mspPort->c_state == MSP_HEADER_ARROW) {
         if (c > MSP_PORT_INBUF_SIZE) {
             mspPort->c_state = MSP_IDLE;
@@ -173,12 +186,29 @@ static mspPostProcessFnPtr mspSerialProcessReceivedCommand(mspPort_t *msp, mspPr
     return mspPostProcessFn;
 }
 
+
+static void mspSerialProcessReceivedReply(mspPort_t *msp, mspProcessReplyFnPtr mspProcessReplyFn)
+{
+    mspPacket_t reply = {
+        .buf = {
+            .ptr = msp->inBuf,
+            .end = msp->inBuf + msp->dataSize,
+        },
+        .cmd = msp->cmdMSP,
+        .result = 0,
+    };
+
+    mspProcessReplyFn(&reply);
+
+    msp->c_state = MSP_IDLE;
+}
+
 /*
  * Process MSP commands from serial ports configured as MSP ports.
  *
  * Called periodically by the scheduler.
  */
-void mspSerialProcess(mspEvaluateNonMspData_e evaluateNonMspData, mspProcessCommandFnPtr mspProcessCommandFn)
+void mspSerialProcess(mspEvaluateNonMspData_e evaluateNonMspData, mspProcessCommandFnPtr mspProcessCommandFn, mspProcessReplyFnPtr mspProcessReplyFn)
 {
     for (uint8_t portIndex = 0; portIndex < MAX_MSP_PORT_COUNT; portIndex++) {
         mspPort_t * const mspPort = &mspPorts[portIndex];
@@ -196,7 +226,11 @@ void mspSerialProcess(mspEvaluateNonMspData_e evaluateNonMspData, mspProcessComm
             }
 
             if (mspPort->c_state == MSP_COMMAND_RECEIVED) {
-                mspPostProcessFn = mspSerialProcessReceivedCommand(mspPort, mspProcessCommandFn);
+                if (mspPort->packetType == MSP_PACKET_COMMAND) {
+                    mspPostProcessFn = mspSerialProcessReceivedCommand(mspPort, mspProcessCommandFn);
+                } else if (mspPort->packetType == MSP_PACKET_REPLY) {
+                    mspSerialProcessReceivedReply(mspPort, mspProcessReplyFn);
+                }
                 break; // process one command at a time so as not to block.
             }
         }
@@ -207,6 +241,21 @@ void mspSerialProcess(mspEvaluateNonMspData_e evaluateNonMspData, mspProcessComm
     }
 }
 
+bool mspSerialWaiting(void)
+{
+    for (uint8_t portIndex = 0; portIndex < MAX_MSP_PORT_COUNT; portIndex++) {
+        mspPort_t * const mspPort = &mspPorts[portIndex];
+        if (!mspPort->port) {
+            continue;
+        }
+
+        if (serialRxBytesWaiting(mspPort->port)) {
+            return true;
+        }
+    }
+    return false;
+}
+
 void mspSerialInit(void)
 {
     memset(mspPorts, 0, sizeof(mspPorts));
@@ -215,7 +264,7 @@ void mspSerialInit(void)
 
 int mspSerialPush(uint8_t cmd, const uint8_t *data, int datalen)
 {
-    static uint8_t pushBuf[30];
+    static uint8_t pushBuf[34];
     int ret = 0;
 
     mspPacket_t push = {
diff --git a/src/main/msp/msp_serial.h b/src/main/msp/msp_serial.h
index c6faf448df..a1decd84b5 100644
--- a/src/main/msp/msp_serial.h
+++ b/src/main/msp/msp_serial.h
@@ -32,6 +32,11 @@ typedef enum {
     MSP_COMMAND_RECEIVED
 } mspState_e;
 
+typedef enum {
+    MSP_PACKET_COMMAND,
+    MSP_PACKET_REPLY
+} mspPacketType_e;
+
 typedef enum {
     MSP_EVALUATE_NON_MSP_DATA,
     MSP_SKIP_NON_MSP_DATA
@@ -58,12 +63,14 @@ typedef struct mspPort_s {
     uint8_t checksum;
     uint8_t cmdMSP;
     mspState_e c_state;
+    mspPacketType_e packetType;
     uint8_t inBuf[MSP_PORT_INBUF_SIZE];
 } mspPort_t;
 
 
 void mspSerialInit(void);
-void mspSerialProcess(mspEvaluateNonMspData_e evaluateNonMspData, mspProcessCommandFnPtr mspProcessCommandFn);
+bool mspSerialWaiting(void);
+void mspSerialProcess(mspEvaluateNonMspData_e evaluateNonMspData, mspProcessCommandFnPtr mspProcessCommandFn, mspProcessReplyFnPtr mspProcessReplyFn);
 void mspSerialAllocatePorts(void);
 void mspSerialReleasePortIfAllocated(struct serialPort_s *serialPort);
 int mspSerialPush(uint8_t cmd, const uint8_t *data, int datalen);
diff --git a/src/main/scheduler/scheduler.h b/src/main/scheduler/scheduler.h
index 96fc785689..69641c4920 100644
--- a/src/main/scheduler/scheduler.h
+++ b/src/main/scheduler/scheduler.h
@@ -95,6 +95,9 @@ typedef enum {
 #ifdef OSD
     TASK_OSD,
 #endif
+#ifdef USE_OSD_SLAVE
+    TASK_OSD_SLAVE,
+#endif
 #ifdef USE_BST
     TASK_BST_MASTER_PROCESS,
 #endif
diff --git a/src/main/target/SPRACINGF3EVO/target.h b/src/main/target/SPRACINGF3EVO/target.h
index aee30e440d..eb3f85c1c5 100755
--- a/src/main/target/SPRACINGF3EVO/target.h
+++ b/src/main/target/SPRACINGF3EVO/target.h
@@ -145,6 +145,10 @@
 #define CURRENT_METER_ADC_PIN   PA5
 #endif
 
+#define OSD
+#define USE_OSD_OVER_MSP_DISPLAYPORT
+#undef USE_DASHBOARD
+
 #define TRANSPONDER
 
 #define ENABLE_BLACKBOX_LOGGING_ON_SDCARD_BY_DEFAULT
diff --git a/src/main/target/SPRACINGF3OSD/config.c b/src/main/target/SPRACINGF3OSD/config.c
new file mode 100644
index 0000000000..52d3b5b40d
--- /dev/null
+++ b/src/main/target/SPRACINGF3OSD/config.c
@@ -0,0 +1,36 @@
+/*
+ * This file is part of Cleanflight.
+ *
+ * Cleanflight is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * Cleanflight is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with Cleanflight.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <stdbool.h>
+#include <stdint.h>
+
+#include <platform.h>
+
+#include "drivers/serial.h"
+
+#include "io/serial.h"
+
+#include "config/feature.h"
+
+#include "fc/config.h"
+
+#ifdef TARGET_CONFIG
+void targetConfiguration(void)
+{
+    serialConfigMutable()->portConfigs[1].functionMask = FUNCTION_MSP; // To connect to FC.
+}
+#endif
diff --git a/src/main/target/SPRACINGF3OSD/target.c b/src/main/target/SPRACINGF3OSD/target.c
new file mode 100644
index 0000000000..ebd888f4bb
--- /dev/null
+++ b/src/main/target/SPRACINGF3OSD/target.c
@@ -0,0 +1,36 @@
+/*
+ * This file is part of Cleanflight.
+ *
+ * Cleanflight is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * Cleanflight is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with Cleanflight.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <stdint.h>
+
+#include <platform.h>
+#include "drivers/io.h"
+
+#include "drivers/timer.h"
+#include "drivers/timer_def.h"
+#include "drivers/dma.h"
+
+const timerHardware_t timerHardware[USABLE_TIMER_CHANNEL_COUNT] = {
+
+    DEF_TIM(TIM3,  CH3, PB0,  TIM_USE_MOTOR, 1 ), // DMA1_Channel2
+    DEF_TIM(TIM3,  CH4, PB1,  TIM_USE_MOTOR, 1 ), // DMA1_Channel4
+    DEF_TIM(TIM16, CH1, PB4,  TIM_USE_MOTOR, 1 ), // DMA1_Channel3 or DMA1_Channel6 with Remap (need remap to free SPI1_TX for Flash)
+    DEF_TIM(TIM17, CH1, PB5,  TIM_USE_MOTOR, 1 ), // DMA1_Channel1 or DMA1_Channel7 with Remap (need remap, ADC1 is on DMA1_Channel1)
+
+    DEF_TIM(TIM1,  CH1, PA8,  TIM_USE_TRANSPONDER, 0 ),
+};
+
diff --git a/src/main/target/SPRACINGF3OSD/target.h b/src/main/target/SPRACINGF3OSD/target.h
new file mode 100644
index 0000000000..6414d2f902
--- /dev/null
+++ b/src/main/target/SPRACINGF3OSD/target.h
@@ -0,0 +1,115 @@
+/*
+ * This file is part of Cleanflight.
+ *
+ * Cleanflight is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * Cleanflight is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with Cleanflight.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#pragma once
+
+#define TARGET_BOARD_IDENTIFIER "SOF3"
+#define TARGET_CONFIG
+
+#define CONFIG_FASTLOOP_PREFERRED_ACC ACC_DEFAULT
+
+#define LED0                    PA15
+
+#define USE_EXTI
+
+
+#define GYRO
+#define USE_FAKE_GYRO
+
+#define ACC
+#define USE_FAKE_ACC
+
+#define REMAP_TIM16_DMA
+#define REMAP_TIM17_DMA
+
+#define USE_VCP
+#define USE_UART1
+#define USE_UART3
+#define SERIAL_PORT_COUNT       3
+
+#define UART1_TX_PIN            PA9
+#define UART1_RX_PIN            PA10
+
+#define BUS_SWITCH_PIN          PB3 // connects and disconnects UART1 from external devices
+
+#define UART3_TX_PIN            PB10
+#define UART3_RX_PIN            PB11
+
+#define USE_I2C
+#define USE_I2C_DEVICE_1
+#define I2C_DEVICE              (I2CDEV_1)
+
+#define USE_SPI
+#define USE_SPI_DEVICE_1 // Flash Chip
+#define USE_SPI_DEVICE_2 // MAX7456
+
+#define SPI1_NSS_PIN            PA4
+#define SPI1_SCK_PIN            PA5
+#define SPI1_MISO_PIN           PA6
+#define SPI1_MOSI_PIN           PA7
+
+#define SPI2_NSS_PIN            PB12
+#define SPI2_SCK_PIN            PB13
+#define SPI2_MISO_PIN           PB14
+#define SPI2_MOSI_PIN           PB15
+
+#define USE_MAX7456
+#define MAX7456_SPI_INSTANCE    SPI2
+#define MAX7456_SPI_CS_PIN      SPI2_NSS_PIN
+#define MAX7456_NRST_PIN        PB2
+
+#define MAX7456_DMA_CHANNEL_TX              DMA1_Channel5
+#define MAX7456_DMA_CHANNEL_RX              DMA1_Channel4
+#define MAX7456_DMA_IRQ_HANDLER_ID          DMA1_CH4_HANDLER
+
+#define BOARD_HAS_VOLTAGE_DIVIDER
+#define BOARD_HAS_CURRENT_SENSOR
+
+#define USE_ADC
+#define ADC_INSTANCE            ADC1
+#define VBAT_ADC_PIN            PA2
+#define CURRENT_METER_ADC_PIN   PA3
+#define VOLTAGE_12V_ADC_PIN     PA0
+#define VOLTAGE_5V_ADC_PIN      PA1
+
+#define TRANSPONDER
+
+#define USE_OSD_SLAVE
+
+#undef OSD
+#undef GPS
+#undef BLACKBOX
+#undef TELEMETRY
+#undef USE_SERVOS
+#undef VTX_COMMON
+#undef VTX_CONTROL
+#undef VTX_SMARTAUDIO
+#undef VTX_TRAMP
+#undef USE_MSP_DISPLAYPORT
+
+
+#define DEFAULT_FEATURES        (FEATURE_TRANSPONDER)
+
+// IO - assuming 303 in 64pin package, TODO
+#define TARGET_IO_PORTA 0xffff
+#define TARGET_IO_PORTB 0xffff
+#define TARGET_IO_PORTC 0xffff
+#define TARGET_IO_PORTD (BIT(2))
+#define TARGET_IO_PORTF (BIT(0)|BIT(1)|BIT(4))
+
+#define USABLE_TIMER_CHANNEL_COUNT 12 // 2xPPM, 6xPWM, UART3 RX/TX, LED Strip, IR.
+#define USED_TIMERS  (TIM_N(1) | TIM_N(2) | TIM_N(3) | TIM_N(8) | TIM_N(15) | TIM_N(16))
diff --git a/src/main/target/SPRACINGF3OSD/target.mk b/src/main/target/SPRACINGF3OSD/target.mk
new file mode 100644
index 0000000000..b9712bcf01
--- /dev/null
+++ b/src/main/target/SPRACINGF3OSD/target.mk
@@ -0,0 +1,6 @@
+F3_TARGETS  += $(TARGET)
+FEATURES    = VCP SDCARD
+
+TARGET_SRC = \
+            drivers/accgyro_fake.c \
+            drivers/max7456.c
diff --git a/src/main/target/SPRACINGF4EVO/target.h b/src/main/target/SPRACINGF4EVO/target.h
index 8427804efd..fde111b64c 100644
--- a/src/main/target/SPRACINGF4EVO/target.h
+++ b/src/main/target/SPRACINGF4EVO/target.h
@@ -31,7 +31,7 @@
 #define BEEPER                  PC15
 #define BEEPER_INVERTED
 
-#define INVERTER_PIN_UART2     PB2
+#define INVERTER_PIN_UART2      PB2
 
 #define USE_EXTI
 #define MPU_INT_EXTI            PC13
@@ -154,6 +154,8 @@
 
 #define BOARD_HAS_VOLTAGE_DIVIDER
 
+#define OSD
+#define USE_OSD_OVER_MSP_DISPLAYPORT
 
 #define LED_STRIP
 #define TRANSPONDER