diff --git a/radio/src/datastructs.h b/radio/src/datastructs.h
index 2267af0b8..833abd52c 100644
--- a/radio/src/datastructs.h
+++ b/radio/src/datastructs.h
@@ -661,7 +661,7 @@ PACK(struct TrainerData {
 
 #if defined(PCBHORUS)
   #define EXTRA_GENERAL_FIELDS \
-    NOBACKUP(uint8_t serial2Mode); \
+    NOBACKUP(uint8_t auxSerialMode); \
     uint32_t switchConfig; \
     uint16_t potsConfig; /* two bits per pot */ \
     uint8_t slidersConfig; /* 1 bit per slider */ \
@@ -680,7 +680,7 @@ PACK(struct TrainerData {
     #define BLUETOOTH_FIELDS
   #endif
   #define EXTRA_GENERAL_FIELDS \
-    uint8_t  serial2Mode:4; \
+    uint8_t  auxSerialMode:4; \
     uint8_t  slidersConfig:4; \
     uint8_t  potsConfig; /* two bits per pot */\
     uint8_t  backlightColor; \
diff --git a/radio/src/debug.cpp b/radio/src/debug.cpp
index e0fda135a..f7a0bd1f5 100644
--- a/radio/src/debug.cpp
+++ b/radio/src/debug.cpp
@@ -47,7 +47,7 @@ void debugPrintf(const char * format, ...)
 #if defined(DEBUG_TRACE_BUFFER)
 static struct TraceElement traceBuffer[TRACE_BUFFER_LEN];
 static uint8_t traceBufferPos;
-extern Fifo<uint8_t, 512> serial2TxFifo;
+extern Fifo<uint8_t, 512> auxSerialTxFifo;
 gtime_t filltm(const gtime_t *t, struct gtm *tp);
 
 void trace_event(enum TraceEvent event, uint32_t data)
@@ -93,7 +93,7 @@ void dumpTraceBuffer()
     if (traceBuffer[n].time == 0 && traceBuffer[n].time_ms == 0) break;
 #if !defined(SIMU)
     if ((n % 5) == 0) {
-      while (!serial2TxFifo.isEmpty()) {
+      while (!auxSerialTxFifo.isEmpty()) {
         RTOS_WAIT_TICKS(1);
       }
     }
diff --git a/radio/src/debug.h b/radio/src/debug.h
index 640d36a4a..2fee847ee 100644
--- a/radio/src/debug.h
+++ b/radio/src/debug.h
@@ -34,7 +34,7 @@
 extern "C" {
 #endif
 
-uint8_t serial2TracesEnabled();
+uint8_t auxSerialTracesEnabled();
 
 #if defined(SIMU)
   typedef void (*traceCallbackFunc)(const char * text);
diff --git a/radio/src/gui/212x64/radio_hardware.cpp b/radio/src/gui/212x64/radio_hardware.cpp
index 44c550b30..16868612d 100644
--- a/radio/src/gui/212x64/radio_hardware.cpp
+++ b/radio/src/gui/212x64/radio_hardware.cpp
@@ -235,9 +235,9 @@ void menuRadioHardware(event_t event)
 
 #if defined(AUX_SERIAL)
       case ITEM_RADIO_HARDWARE_UART3_MODE:
-        g_eeGeneral.serial2Mode = editChoice(HW_SETTINGS_COLUMN, y, STR_UART3MODE, STR_UART3MODES, g_eeGeneral.serial2Mode, 0, UART_MODE_MAX, attr, event);
+        g_eeGeneral.auxSerialMode = editChoice(HW_SETTINGS_COLUMN, y, STR_UART3MODE, STR_UART3MODES, g_eeGeneral.auxSerialMode, 0, UART_MODE_MAX, attr, event);
         if (attr && checkIncDec_Ret) {
-          serial2Init(g_eeGeneral.serial2Mode, modelTelemetryProtocol());
+          auxSerialInit(g_eeGeneral.auxSerialMode, modelTelemetryProtocol());
         }
         break;
 #endif
diff --git a/radio/src/gui/480x272/radio_hardware.cpp b/radio/src/gui/480x272/radio_hardware.cpp
index 8886e8366..86c2ad01c 100644
--- a/radio/src/gui/480x272/radio_hardware.cpp
+++ b/radio/src/gui/480x272/radio_hardware.cpp
@@ -218,9 +218,9 @@ bool menuRadioHardware(event_t event)
 #if defined(AUX_SERIAL)
       case ITEM_RADIO_HARDWARE_UART3_MODE:
         lcdDrawText(MENUS_MARGIN_LEFT, y, STR_UART3MODE);
-        g_eeGeneral.serial2Mode = editChoice(HW_SETTINGS_COLUMN+50, y, STR_UART3MODES, g_eeGeneral.serial2Mode, 0, UART_MODE_MAX, attr, event);
+        g_eeGeneral.auxSerialMode = editChoice(HW_SETTINGS_COLUMN+50, y, STR_UART3MODES, g_eeGeneral.auxSerialMode, 0, UART_MODE_MAX, attr, event);
         if (attr && checkIncDec_Ret) {
-          serial2Init(g_eeGeneral.serial2Mode, modelTelemetryProtocol());
+          auxSerialInit(g_eeGeneral.auxSerialMode, modelTelemetryProtocol());
         }
         break;
 #endif
diff --git a/radio/src/gui/gui_common.cpp b/radio/src/gui/gui_common.cpp
index e36c706d5..9cc017a76 100644
--- a/radio/src/gui/gui_common.cpp
+++ b/radio/src/gui/gui_common.cpp
@@ -686,7 +686,7 @@ bool isRfProtocolAvailable(int protocol)
 bool isTelemetryProtocolAvailable(int protocol)
 {
 #if defined(PCBTARANIS)
-  if (protocol == PROTOCOL_TELEMETRY_FRSKY_D_SECONDARY && g_eeGeneral.serial2Mode != UART_MODE_TELEMETRY) {
+  if (protocol == PROTOCOL_TELEMETRY_FRSKY_D_SECONDARY && g_eeGeneral.auxSerialMode != UART_MODE_TELEMETRY) {
     return false;
   }
 #endif
diff --git a/radio/src/lua/api_general.cpp b/radio/src/lua/api_general.cpp
index 25b074cff..64610142c 100644
--- a/radio/src/lua/api_general.cpp
+++ b/radio/src/lua/api_general.cpp
@@ -1363,10 +1363,10 @@ static int luaSerialWrite(lua_State * L)
   }
   #endif
   #if defined(AUX_SERIAL)
-  if (serial2Mode == UART_MODE_LUA) {
+  if (auxSerialMode == UART_MODE_LUA) {
     size_t wr_len = len;
     const char* p = str;
-    while(wr_len--) serial2Putc(*p++);
+    while(wr_len--) auxSerialPutc(*p++);
   }
   #endif
 #else
diff --git a/radio/src/myeeprom.h b/radio/src/myeeprom.h
index ccbfd0109..aefdbd371 100644
--- a/radio/src/myeeprom.h
+++ b/radio/src/myeeprom.h
@@ -36,10 +36,10 @@
 
 #if defined(PCBHORUS)
   #define IS_TRAINER_EXTERNAL_MODULE()    false
-  #define HAS_WIRELESS_TRAINER_HARDWARE() (g_eeGeneral.serial2Mode==UART_MODE_SBUS_TRAINER)
+  #define HAS_WIRELESS_TRAINER_HARDWARE() (g_eeGeneral.auxSerialMode==UART_MODE_SBUS_TRAINER)
 #elif defined(PCBTARANIS)
   #define IS_TRAINER_EXTERNAL_MODULE()      (g_model.trainerData.mode == TRAINER_MODE_MASTER_SBUS_EXTERNAL_MODULE || g_model.trainerData.mode == TRAINER_MODE_MASTER_CPPM_EXTERNAL_MODULE)
-  #define HAS_WIRELESS_TRAINER_HARDWARE()   (g_eeGeneral.serial2Mode==UART_MODE_SBUS_TRAINER)
+  #define HAS_WIRELESS_TRAINER_HARDWARE()   (g_eeGeneral.auxSerialMode==UART_MODE_SBUS_TRAINER)
 #else
   #define IS_TRAINER_EXTERNAL_MODULE()    false
 #endif
diff --git a/radio/src/opentx.cpp b/radio/src/opentx.cpp
index 84f84134b..f0b1c3a9a 100644
--- a/radio/src/opentx.cpp
+++ b/radio/src/opentx.cpp
@@ -1812,7 +1812,7 @@ void opentxInit()
 #endif  // #if !defined(EEPROM)
 
 #if defined(AUX_SERIAL)
-  serial2Init(g_eeGeneral.serial2Mode, modelTelemetryProtocol());
+  auxSerialInit(g_eeGeneral.auxSerialMode, modelTelemetryProtocol());
 #endif
 
 #if defined(PCBTARANIS)
diff --git a/radio/src/serial.cpp b/radio/src/serial.cpp
index beab793a4..953a865f5 100644
--- a/radio/src/serial.cpp
+++ b/radio/src/serial.cpp
@@ -31,8 +31,8 @@ void serialPutc(char c) {
     usbSerialPutc(c);
 #endif
 #if defined(AUX_SERIAL)
-  if (serial2TracesEnabled())
-    serial2Putc(c);
+  if (auxSerialTracesEnabled())
+    auxSerialPutc(c);
 #endif
 }
 
diff --git a/radio/src/storage/conversions/conversions_216_218.cpp b/radio/src/storage/conversions/conversions_216_218.cpp
index 9839b58f0..f5b5d444a 100644
--- a/radio/src/storage/conversions/conversions_216_218.cpp
+++ b/radio/src/storage/conversions/conversions_216_218.cpp
@@ -796,7 +796,7 @@ PACK(typedef struct {
   int8_t   varioRepeat;
   int8_t   backgroundVolume;
 
-  TARANIS_FIELD(uint8_t serial2Mode:6)
+  TARANIS_FIELD(uint8_t auxSerialMode:6)
   TARANIS_FIELD(uint8_t slidersConfig:2)
   TARANIS_FIELD(uint8_t potsConfig)
   TARANIS_FIELD(uint8_t backlightColor)
@@ -867,7 +867,7 @@ void convertRadioData_217_to_218(RadioData &settings)
   ConvertSpecialFunctions_217_to_218((CustomFunctionData_v218 *)settings.customFn, settings_v217.customFn);
 
 #if defined(PCBTARANIS)
-  settings.serial2Mode = settings_v217.serial2Mode;
+  settings.auxSerialMode = settings_v217.auxSerialMode;
   settings.slidersConfig = settings_v217.slidersConfig;
   settings.potsConfig = settings_v217.potsConfig;
   settings.backlightColor = settings_v217.backlightColor;
diff --git a/radio/src/storage/conversions/conversions_218_219.cpp b/radio/src/storage/conversions/conversions_218_219.cpp
index 72017865d..d2703bcb7 100644
--- a/radio/src/storage/conversions/conversions_218_219.cpp
+++ b/radio/src/storage/conversions/conversions_218_219.cpp
@@ -273,11 +273,11 @@ void convertRadioData_218_to_219(RadioData & settings)
 #if defined(PCBHORUS)
   RadioData_v218 settings_v218 = (RadioData_v218 &)settings;
 
-  memcpy(&settings.chkSum, &settings_v218.chkSum, offsetof(RadioData, serial2Mode) - offsetof(RadioData, chkSum));
+  memcpy(&settings.chkSum, &settings_v218.chkSum, offsetof(RadioData, auxSerialMode) - offsetof(RadioData, chkSum));
   memcpy(&settings.calib[NUM_STICKS + 5], &settings_v218.calib[NUM_STICKS + 3], sizeof(CalibData) * (STORAGE_NUM_SLIDERS + STORAGE_NUM_MOUSE_ANALOGS));
   memclear(&settings.calib[NUM_STICKS + 3], sizeof(CalibData) * 2);
 
-  settings.serial2Mode = settings_v218.serial2Mode;
+  settings.auxSerialMode = settings_v218.auxSerialMode;
   settings.switchConfig = settings_v218.switchConfig;
   settings.potsConfig = settings_v218.potsConfig;
   settings.slidersConfig = settings_v218.slidersConfig;
diff --git a/radio/src/storage/conversions/datastructs_218.h b/radio/src/storage/conversions/datastructs_218.h
index a54425842..ce0725471 100644
--- a/radio/src/storage/conversions/datastructs_218.h
+++ b/radio/src/storage/conversions/datastructs_218.h
@@ -506,7 +506,7 @@ static inline void check_struct_218()
 #if defined(PCBHORUS)
 #define EXTRA_GENERAL_FIELDS_218 \
     EXTRA_GENERAL_FIELDS_GENERAL_218 \
-    uint8_t  serial2Mode:4; \
+    uint8_t  auxSerialMode:4; \
     uint8_t  slidersConfig:4; \
     uint32_t switchConfig; \
     uint8_t  potsConfig; /* two bits per pot */ \
@@ -526,7 +526,7 @@ static inline void check_struct_218()
 #endif
 #define EXTRA_GENERAL_FIELDS_218 \
     EXTRA_GENERAL_FIELDS_GENERAL_218 \
-    uint8_t  serial2Mode:4; \
+    uint8_t  auxSerialMode:4; \
     uint8_t  slidersConfig:4; \
     uint8_t  potsConfig; /* two bits per pot */\
     uint8_t  backlightColor; \
diff --git a/radio/src/targets/common/arm/stm32/serial2_driver.cpp b/radio/src/targets/common/arm/stm32/aux_serial_driver.cpp
similarity index 82%
rename from radio/src/targets/common/arm/stm32/serial2_driver.cpp
rename to radio/src/targets/common/arm/stm32/aux_serial_driver.cpp
index 0fbd4605e..8d49dd53d 100644
--- a/radio/src/targets/common/arm/stm32/serial2_driver.cpp
+++ b/radio/src/targets/common/arm/stm32/aux_serial_driver.cpp
@@ -20,11 +20,11 @@
 
 #include "opentx.h"
 
-uint8_t serial2Mode = 0;
-Fifo<uint8_t, 512> serial2TxFifo;
-DMAFifo<32> serial2RxFifo __DMA (AUX_SERIAL_DMA_Stream_RX);
+uint8_t auxSerialMode = 0;
+Fifo<uint8_t, 512> auxSerialTxFifo;
+DMAFifo<32> auxSerialRxFifo __DMA (AUX_SERIAL_DMA_Stream_RX);
 
-void uart3Setup(unsigned int baudrate, bool dma)
+void auxSerialSetup(unsigned int baudrate, bool dma)
 {
   USART_InitTypeDef USART_InitStructure;
   GPIO_InitTypeDef GPIO_InitStructure;
@@ -49,14 +49,14 @@ void uart3Setup(unsigned int baudrate, bool dma)
 
   if (dma) {
     DMA_InitTypeDef DMA_InitStructure;
-    serial2RxFifo.clear();
+    auxSerialRxFifo.clear();
     USART_ITConfig(AUX_SERIAL_USART, USART_IT_RXNE, DISABLE);
     USART_ITConfig(AUX_SERIAL_USART, USART_IT_TXE, DISABLE);
     DMA_InitStructure.DMA_Channel = AUX_SERIAL_DMA_Channel_RX;
     DMA_InitStructure.DMA_PeripheralBaseAddr = CONVERT_PTR_UINT(&AUX_SERIAL_USART->DR);
-    DMA_InitStructure.DMA_Memory0BaseAddr = CONVERT_PTR_UINT(serial2RxFifo.buffer());
+    DMA_InitStructure.DMA_Memory0BaseAddr = CONVERT_PTR_UINT(auxSerialRxFifo.buffer());
     DMA_InitStructure.DMA_DIR = DMA_DIR_PeripheralToMemory;
-    DMA_InitStructure.DMA_BufferSize = serial2RxFifo.size();
+    DMA_InitStructure.DMA_BufferSize = auxSerialRxFifo.size();
     DMA_InitStructure.DMA_PeripheralInc = DMA_PeripheralInc_Disable;
     DMA_InitStructure.DMA_MemoryInc = DMA_MemoryInc_Enable;
     DMA_InitStructure.DMA_PeripheralDataSize = DMA_PeripheralDataSize_Byte;
@@ -81,66 +81,69 @@ void uart3Setup(unsigned int baudrate, bool dma)
   }
 }
 
-void serial2Init(unsigned int mode, unsigned int protocol)
+void auxSerialInit(unsigned int mode, unsigned int protocol)
 {
-  serial2Stop();
+  auxSerialStop();
 
-  serial2Mode = mode;
+  auxSerialMode = mode;
 
   switch (mode) {
     case UART_MODE_TELEMETRY_MIRROR:
 #if defined(CROSSFIRE)
       if (protocol == PROTOCOL_TELEMETRY_CROSSFIRE) {
-        uart3Setup(CROSSFIRE_TELEM_MIRROR_BAUDRATE, false);
+        auxSerialSetup(CROSSFIRE_TELEM_MIRROR_BAUDRATE, false);
         break;
       }
 #endif
-      uart3Setup(FRSKY_SPORT_BAUDRATE, false);
+      auxSerialSetup(FRSKY_SPORT_BAUDRATE, false);
       break;
+
 #if defined(DEBUG) || defined(CLI)
     case UART_MODE_DEBUG:
-      uart3Setup(DEBUG_BAUDRATE, false);
+      auxSerialSetup(DEBUG_BAUDRATE, false);
       break;
 #endif
+
     case UART_MODE_TELEMETRY:
       if (protocol == PROTOCOL_TELEMETRY_FRSKY_D_SECONDARY) {
-        uart3Setup(FRSKY_D_BAUDRATE, true);
+        auxSerialSetup(FRSKY_D_BAUDRATE, true);
       }
       break;
+
     case UART_MODE_LUA:
-      uart3Setup(DEBUG_BAUDRATE, false);
+      auxSerialSetup(DEBUG_BAUDRATE, false);
   }
 }
 
-void serial2Putc(char c)
+void auxSerialPutc(char c)
 {
 #if !defined(SIMU)
   int n = 0;
-  while (serial2TxFifo.isFull()) {
+  while (auxSerialTxFifo.isFull()) {
     delay_ms(1);
     if (++n > 100) return;
   }
-  serial2TxFifo.push(c);
+  auxSerialTxFifo.push(c);
   USART_ITConfig(AUX_SERIAL_USART, USART_IT_TXE, ENABLE);
 #endif
 }
 
-void serial2SbusInit()
+void auxSerialSbusInit()
 {
-  uart3Setup(SBUS_BAUDRATE, true);
+  auxSerialSetup(SBUS_BAUDRATE, true);
   AUX_SERIAL_USART->CR1 |= USART_CR1_M | USART_CR1_PCE ;
 }
 
-void serial2Stop()
+void auxSerialStop()
 {
   DMA_DeInit(AUX_SERIAL_DMA_Stream_RX);
   USART_DeInit(AUX_SERIAL_USART);
 }
 
-uint8_t serial2TracesEnabled()
+uint8_t auxSerialTracesEnabled()
 {
 #if defined(DEBUG)
-  return (serial2Mode == UART_MODE_DEBUG);
+  return (auxSerialMode == UART_MODE_DEBUG);
 #else
   return false;
 #endif
@@ -153,7 +156,7 @@ extern "C" void AUX_SERIAL_USART_IRQHandler(void)
   // Send
   if (USART_GetITStatus(AUX_SERIAL_USART, USART_IT_TXE) != RESET) {
     uint8_t txchar;
-    if (serial2TxFifo.pop(txchar)) {
+    if (auxSerialTxFifo.pop(txchar)) {
       /* Write one byte to the transmit data register */
       USART_SendData(AUX_SERIAL_USART, txchar);
     }
@@ -169,7 +172,7 @@ extern "C" void AUX_SERIAL_USART_IRQHandler(void)
     while (status & (USART_FLAG_RXNE | USART_FLAG_ERRORS)) {
       uint8_t data = AUX_SERIAL_USART->DR;
       if (!(status & USART_FLAG_ERRORS)) {
-        switch (serial2Mode) {
+        switch (auxSerialMode) {
           case UART_MODE_DEBUG:
             cliRxFifo.push(data);
             break;
diff --git a/radio/src/targets/common/arm/stm32/bootloader/CMakeLists.txt b/radio/src/targets/common/arm/stm32/bootloader/CMakeLists.txt
index 87bbe0ccb..fec7b825f 100644
--- a/radio/src/targets/common/arm/stm32/bootloader/CMakeLists.txt
+++ b/radio/src/targets/common/arm/stm32/bootloader/CMakeLists.txt
@@ -116,7 +116,7 @@ else()
       ${BOOTLOADER_SRC}
       ../../../../../${STM32LIB_DIR}/STM32F4xx_StdPeriph_Driver/src/stm32f4xx_usart.c
       ../../../../../serial.cpp
-      ../serial2_driver.cpp
+      ../aux_serial_driver.cpp
       )
   endif()
 endif()
diff --git a/radio/src/targets/common/arm/stm32/bootloader/boot.cpp b/radio/src/targets/common/arm/stm32/bootloader/boot.cpp
index 46d1fadd9..9555001f6 100644
--- a/radio/src/targets/common/arm/stm32/bootloader/boot.cpp
+++ b/radio/src/targets/common/arm/stm32/bootloader/boot.cpp
@@ -231,10 +231,11 @@ int main()
   delaysInit(); // needed for lcdInit()
 
 #if defined(DEBUG)
-  serial2Init(UART_MODE_DEBUG, 0); // default serial mode (None if DEBUG not defined)
+  auxSerialInit(UART_MODE_DEBUG, 0); // default serial mode (None if DEBUG not defined)
 #endif
 
   __enable_irq();
+
   TRACE("\nBootloader started :)");
 
   lcdInit();
diff --git a/radio/src/targets/horus/CMakeLists.txt b/radio/src/targets/horus/CMakeLists.txt
index d59086cc9..14fd9c4e9 100644
--- a/radio/src/targets/horus/CMakeLists.txt
+++ b/radio/src/targets/horus/CMakeLists.txt
@@ -118,7 +118,7 @@ if(INTERNAL_GPS)
   message("Horus: Internal GPS enabled")
 endif()
 
-set(AUX_SERIAL_DRIVER ../common/arm/stm32/serial2_driver.cpp)
+set(AUX_SERIAL_DRIVER ../common/arm/stm32/aux_serial_driver.cpp)
 
 set(GVAR_SCREEN model_gvars.cpp)
 
diff --git a/radio/src/targets/horus/board.cpp b/radio/src/targets/horus/board.cpp
index 239ba0adc..c30c9b8ff 100644
--- a/radio/src/targets/horus/board.cpp
+++ b/radio/src/targets/horus/board.cpp
@@ -178,7 +178,7 @@ void boardInit()
   delaysInit();
 
 #if defined(DEBUG)
-  serial2Init(0, 0); // default serial mode (None if DEBUG not defined)
+  auxSerialInit(0, 0); // default serial mode (None if DEBUG not defined)
 #endif
 
   __enable_irq();
@@ -261,7 +261,7 @@ void checkTrainerSettings()
         stop_trainer_ppm();
         break;
       case TRAINER_MODE_MASTER_BATTERY_COMPARTMENT:
-        serial2Stop();
+        auxSerialStop();
     }
 
     currentTrainerMode = requiredTrainerMode;
@@ -270,8 +270,8 @@ void checkTrainerSettings()
         init_trainer_ppm();
         break;
       case TRAINER_MODE_MASTER_BATTERY_COMPARTMENT:
-        if (g_eeGeneral.serial2Mode == UART_MODE_SBUS_TRAINER) {
-          serial2SbusInit();
+        if (g_eeGeneral.auxSerialMode == UART_MODE_SBUS_TRAINER) {
+          auxSerialSbusInit();
           break;
         }
         // no break
diff --git a/radio/src/targets/horus/board.h b/radio/src/targets/horus/board.h
index fecd0cde0..719c5c124 100644
--- a/radio/src/targets/horus/board.h
+++ b/radio/src/targets/horus/board.h
@@ -631,18 +631,18 @@ void gpsSendByte(uint8_t byte);
 // Second serial port driver
 #define AUX_SERIAL
 #define DEBUG_BAUDRATE                 115200
-extern uint8_t serial2Mode;
-void serial2Init(unsigned int mode, unsigned int protocol);
-void serial2Putc(char c);
-#define serial2TelemetryInit(protocol) serial2Init(UART_MODE_TELEMETRY, protocol)
-void serial2SbusInit(void);
-void serial2Stop(void);
+extern uint8_t auxSerialMode;
+void auxSerialInit(unsigned int mode, unsigned int protocol);
+void auxSerialPutc(char c);
+#define auxSerialTelemetryInit(protocol) auxSerialInit(UART_MODE_TELEMETRY, protocol)
+void auxSerialSbusInit(void);
+void auxSerialStop(void);
 #define USART_FLAG_ERRORS              (USART_FLAG_ORE | USART_FLAG_NE | USART_FLAG_FE | USART_FLAG_PE)
 
 // BT driver
 #define BT_TX_FIFO_SIZE    64
 #define BT_RX_FIFO_SIZE    128
-#define BLUETOOTH_BOOTLOADER_BAUDRATE   230400
+#define BLUETOOTH_BOOTLOADER_BAUDRATE  230400
 #define BLUETOOTH_FACTORY_BAUDRATE     57600
 #define BLUETOOTH_DEFAULT_BAUDRATE     115200
 void bluetoothInit(uint32_t baudrate, bool enable);
@@ -657,7 +657,7 @@ void checkTrainerSettings(void);
 #include "fifo.h"
 #include "dmafifo.h"
 extern DMAFifo<512> telemetryFifo;
-extern DMAFifo<32> serial2RxFifo;
+extern DMAFifo<32> auxSerialRxFifo;
 #endif
 
 #if NUM_PWMSTICKS > 0
diff --git a/radio/src/targets/sky9x/CMakeLists.txt b/radio/src/targets/sky9x/CMakeLists.txt
index 74a77d511..944910749 100644
--- a/radio/src/targets/sky9x/CMakeLists.txt
+++ b/radio/src/targets/sky9x/CMakeLists.txt
@@ -121,7 +121,7 @@ set(TARGET_SRC
   haptic_driver.cpp
   sdcard_driver.cpp
   massstorage.cpp
-  serial2_driver.cpp
+  aux_serial_driver.cpp
   audio_driver.cpp
   trainer_driver.cpp
   )
diff --git a/radio/src/targets/sky9x/serial2_driver.cpp b/radio/src/targets/sky9x/aux_serial_driver.cpp
similarity index 92%
rename from radio/src/targets/sky9x/serial2_driver.cpp
rename to radio/src/targets/sky9x/aux_serial_driver.cpp
index e2ee724fc..9d8f1978c 100644
--- a/radio/src/targets/sky9x/serial2_driver.cpp
+++ b/radio/src/targets/sky9x/aux_serial_driver.cpp
@@ -28,7 +28,7 @@
 /** Pins description corresponding to Rxd,Txd, (UART pins) */
 #define SECOND_SERIAL_PINS        {PINS_UART}
 
-Fifo<uint8_t, 512> serial2RxFifo;
+Fifo<uint8_t, 512> auxSerialRxFifo;
 
 #if !defined(SIMU)
 /*
@@ -37,7 +37,7 @@ Fifo<uint8_t, 512> serial2RxFifo;
  * This function is synchronous (i.e. uses polling).
  * c  Character to send.
  */
-void serial2Putc(const unsigned char c)
+void auxSerialPutc(const unsigned char c)
 {
   Uart *pUart = SECOND_SERIAL_UART;
 
@@ -48,7 +48,7 @@ void serial2Putc(const unsigned char c)
   pUart->UART_THR = c;
 }
 
-uint8_t serial2TracesEnabled()
+uint8_t auxSerialTracesEnabled()
 {
   return false;
 }
@@ -101,7 +101,7 @@ extern "C" void UART0_IRQHandler()
 {
   if ( SECOND_SERIAL_UART->UART_SR & UART_SR_RXRDY )
   {
-    serial2RxFifo.push(SECOND_SERIAL_UART->UART_RHR);
+    auxSerialRxFifo.push(SECOND_SERIAL_UART->UART_RHR);
   }
 }
 
@@ -110,14 +110,14 @@ extern "C" void UART0_IRQHandler()
 #endif
 
 #if defined(TELEMETRY_FRSKY)
-void serial2TelemetryInit(unsigned int /*protocol*/)
+void auxSerialTelemetryInit(unsigned int /*protocol*/)
 {
   SECOND_UART_Configure(FRSKY_D_BAUDRATE, Master_frequency);
 }
 
 bool telemetrySecondPortReceive(uint8_t & data)
 {
-  return serial2RxFifo.pop(data);
+  return auxSerialRxFifo.pop(data);
 }
 #endif
 
diff --git a/radio/src/targets/sky9x/board.h b/radio/src/targets/sky9x/board.h
index 2bc85ebf1..e46da5850 100644
--- a/radio/src/targets/sky9x/board.h
+++ b/radio/src/targets/sky9x/board.h
@@ -388,8 +388,8 @@ void rxPdcUsart( void (*pChProcess)(uint8_t x) );
 void sportSendBuffer(const uint8_t * buffer, uint32_t size);
 
 // Second UART driver
-void serial2TelemetryInit(unsigned int protocol);
-void serial2Putc(const unsigned char c);
+void auxSerialTelemetryInit(unsigned int protocol);
+void auxSerialPutc(const unsigned char c);
 #if defined(__cplusplus)
 bool telemetrySecondPortReceive(uint8_t & data);
 #endif
diff --git a/radio/src/targets/taranis/CMakeLists.txt b/radio/src/targets/taranis/CMakeLists.txt
index c56b3463b..16c076681 100644
--- a/radio/src/targets/taranis/CMakeLists.txt
+++ b/radio/src/targets/taranis/CMakeLists.txt
@@ -23,7 +23,7 @@ if(PCB STREQUAL X9E)
     top_lcd_driver.cpp
     startup_stm32f40_41xxx.s
     )
-  set(AUX_SERIAL_DRIVER ../common/arm/stm32/serial2_driver.cpp)
+  set(AUX_SERIAL_DRIVER ../common/arm/stm32/aux_serial_driver.cpp)
   if(STICKS STREQUAL HORUS)
     add_definitions(-DHORUS_STICKS)
   endif()
@@ -48,7 +48,7 @@ elseif(PCB STREQUAL X9D+)
   set(BITMAPS_TARGET taranis_bitmaps)
   set(FONTS_TARGET taranis_fonts)
   set(LCD_DRIVER lcd_driver_spi.cpp)
-  set(AUX_SERIAL_DRIVER ../common/arm/stm32/serial2_driver.cpp)
+  set(AUX_SERIAL_DRIVER ../common/arm/stm32/aux_serial_driver.cpp)
   set(GVAR_SCREEN model_gvars.cpp)
   set(STATUS_LEDS NO)
 elseif(PCB STREQUAL X9D)
@@ -65,7 +65,7 @@ elseif(PCB STREQUAL X9D)
   set(BITMAPS_TARGET taranis_bitmaps)
   set(FONTS_TARGET taranis_fonts)
   set(LCD_DRIVER lcd_driver_aspi.cpp)
-  set(AUX_SERIAL_DRIVER ../common/arm/stm32/serial2_driver.cpp)
+  set(AUX_SERIAL_DRIVER ../common/arm/stm32/aux_serial_driver.cpp)
   set(GVAR_SCREEN model_gvars.cpp)
   set(STATUS_LEDS NO)
 elseif(PCB STREQUAL X7)
diff --git a/radio/src/targets/taranis/board.cpp b/radio/src/targets/taranis/board.cpp
index 8b093e04c..cb28e03f6 100644
--- a/radio/src/targets/taranis/board.cpp
+++ b/radio/src/targets/taranis/board.cpp
@@ -228,7 +228,7 @@ void boardInit()
   usbInit();
 
 #if defined(DEBUG) && defined(AUX_SERIAL_GPIO)
-  serial2Init(0, 0); // default serial mode (None if DEBUG not defined)
+  auxSerialInit(0, 0); // default serial mode (None if DEBUG not defined)
   TRACE("\nTaranis board started :)");
 #endif
 
@@ -369,7 +369,7 @@ void checkTrainerSettings()
         break;
 #if defined(TRAINER_BATTERY_COMPARTMENT)
       case TRAINER_MODE_MASTER_BATTERY_COMPARTMENT:
-        serial2Stop();
+        auxSerialStop();
 #endif
     }
 
@@ -386,8 +386,8 @@ void checkTrainerSettings()
          break;
 #if defined(TRAINER_BATTERY_COMPARTMENT)
       case TRAINER_MODE_MASTER_BATTERY_COMPARTMENT:
-        if (g_eeGeneral.serial2Mode == UART_MODE_SBUS_TRAINER) {
-          serial2SbusInit();
+        if (g_eeGeneral.auxSerialMode == UART_MODE_SBUS_TRAINER) {
+          auxSerialSbusInit();
           break;
         }
         // no break
diff --git a/radio/src/targets/taranis/board.h b/radio/src/targets/taranis/board.h
index 84137477f..6d26506b9 100644
--- a/radio/src/targets/taranis/board.h
+++ b/radio/src/targets/taranis/board.h
@@ -773,12 +773,12 @@ void hapticOff(void);
 #if defined(AUX_SERIAL_GPIO)
 #define DEBUG_BAUDRATE                  115200
 #define AUX_SERIAL
-extern uint8_t serial2Mode;
-void serial2Init(unsigned int mode, unsigned int protocol);
-void serial2Putc(char c);
-#define serial2TelemetryInit(protocol) serial2Init(UART_MODE_TELEMETRY, protocol)
-void serial2SbusInit(void);
-void serial2Stop(void);
+extern uint8_t auxSerialMode;
+void auxSerialInit(unsigned int mode, unsigned int protocol);
+void auxSerialPutc(char c);
+#define auxSerialTelemetryInit(protocol) auxSerialInit(UART_MODE_TELEMETRY, protocol)
+void auxSerialSbusInit(void);
+void auxSerialStop(void);
 #endif
 
 // BT driver
@@ -876,7 +876,7 @@ void checkTrainerSettings(void);
 #endif
 
 extern Fifo<uint8_t, TELEMETRY_FIFO_SIZE> telemetryFifo;
-extern DMAFifo<32> serial2RxFifo;
+extern DMAFifo<32> auxSerialRxFifo;
 #endif
 
 // Gyro driver
diff --git a/radio/src/targets/taranis/telemetry_driver.cpp b/radio/src/targets/taranis/telemetry_driver.cpp
index 98d98e755..8a3bfb3f6 100644
--- a/radio/src/targets/taranis/telemetry_driver.cpp
+++ b/radio/src/targets/taranis/telemetry_driver.cpp
@@ -186,8 +186,8 @@ uint8_t telemetryGetByte(uint8_t * byte)
 {
 #if defined(AUX_SERIAL)
   if (telemetryProtocol == PROTOCOL_TELEMETRY_FRSKY_D_SECONDARY) {
-    if (serial2Mode == UART_MODE_TELEMETRY)
-      return serial2RxFifo.pop(*byte);
+    if (auxSerialMode == UART_MODE_TELEMETRY)
+      return auxSerialRxFifo.pop(*byte);
     else
       return false;
   }
diff --git a/radio/src/targets/taranis/trainer_driver.cpp b/radio/src/targets/taranis/trainer_driver.cpp
index 1e13deeb1..04cee785e 100644
--- a/radio/src/targets/taranis/trainer_driver.cpp
+++ b/radio/src/targets/taranis/trainer_driver.cpp
@@ -311,7 +311,7 @@ int sbusGetByte(uint8_t * byte)
 #endif
 #if defined(AUX_SERIAL_USART)
     case TRAINER_MODE_MASTER_BATTERY_COMPARTMENT:
-      return serial2RxFifo.pop(*byte);
+      return auxSerialRxFifo.pop(*byte);
 #endif
     default:
       return false;
diff --git a/radio/src/telemetry/crossfire.cpp b/radio/src/telemetry/crossfire.cpp
index e3168cda6..f6bf04f21 100644
--- a/radio/src/telemetry/crossfire.cpp
+++ b/radio/src/telemetry/crossfire.cpp
@@ -185,8 +185,8 @@ void processCrossfireTelemetryFrame()
 void processCrossfireTelemetryData(uint8_t data)
 {
 #if defined(AUX_SERIAL)
-  if (g_eeGeneral.serial2Mode == UART_MODE_TELEMETRY_MIRROR) {
-    serial2Putc(data);
+  if (g_eeGeneral.auxSerialMode == UART_MODE_TELEMETRY_MIRROR) {
+    auxSerialPutc(data);
   }
 #endif
 
diff --git a/radio/src/telemetry/frsky.cpp b/radio/src/telemetry/frsky.cpp
index 3ff91a6a1..6ae34863a 100644
--- a/radio/src/telemetry/frsky.cpp
+++ b/radio/src/telemetry/frsky.cpp
@@ -28,8 +28,8 @@ void processFrskyTelemetryData(uint8_t data)
 #endif
 
 #if defined(AUX_SERIAL)
-  if (g_eeGeneral.serial2Mode == UART_MODE_TELEMETRY_MIRROR) {
-    serial2Putc(data);
+  if (g_eeGeneral.auxSerialMode == UART_MODE_TELEMETRY_MIRROR) {
+    auxSerialPutc(data);
   }
 #endif
 
diff --git a/radio/src/telemetry/telemetry.cpp b/radio/src/telemetry/telemetry.cpp
index 796a8d09e..36d260a21 100644
--- a/radio/src/telemetry/telemetry.cpp
+++ b/radio/src/telemetry/telemetry.cpp
@@ -288,7 +288,7 @@ void telemetryInit(uint8_t protocol)
 #if defined(AUX_SERIAL) || defined(PCBSKY9X)
   else if (protocol == PROTOCOL_TELEMETRY_FRSKY_D_SECONDARY) {
     telemetryPortInit(0, TELEMETRY_SERIAL_DEFAULT);
-    serial2TelemetryInit(PROTOCOL_TELEMETRY_FRSKY_D_SECONDARY);
+    auxSerialTelemetryInit(PROTOCOL_TELEMETRY_FRSKY_D_SECONDARY);
   }
 #endif