diff --git a/radio/src/lcd_common.cpp b/radio/src/lcd_common.cpp
index 8cb854bfc..972f0597b 100644
--- a/radio/src/lcd_common.cpp
+++ b/radio/src/lcd_common.cpp
@@ -136,11 +136,11 @@ void lcdPutPattern(coord_t x, coord_t y, const uint8_t * pattern, uint8_t width,
 void lcd_putcAtt(coord_t x, coord_t y, const unsigned char c, LcdFlags flags)
 {
   const pm_uchar * q;
-  uint32_t fontsize = FONTSIZE(flags);
 
   lcdNextPos = x-1;
 
 #if !defined(BOOT)
+  uint32_t fontsize = FONTSIZE(flags);
   unsigned char c_remapped = 0;
 
   if (fontsize == DBLSIZE || (flags&BOLD)) {
diff --git a/radio/src/opentx.cpp b/radio/src/opentx.cpp
index 3cef91742..e78afb887 100644
--- a/radio/src/opentx.cpp
+++ b/radio/src/opentx.cpp
@@ -2289,20 +2289,7 @@ void perMain()
 #endif
 
 #if defined(PCBTARANIS)
-  uint8_t requiredTrainerMode = g_model.trainerMode;
-  if (requiredTrainerMode != currentTrainerMode) {
-    currentTrainerMode = requiredTrainerMode;
-    if (requiredTrainerMode) {
-      // slave
-      stop_trainer_capture();
-      init_trainer_ppm();
-    }
-    else {
-      // master
-      stop_trainer_ppm();
-      init_trainer_capture();
-    }
-  }
+  checkTrainerSettings();
 #endif
 
 #if defined(PCBTARANIS) && !defined(SIMU)
@@ -2609,7 +2596,7 @@ ISR(TIMER3_CAPT_vect) // G: High frequency noise can cause stack overflo with IS
   else {
     if (ppmInState>0 && ppmInState<=8) {
       if (val>800 && val<2200) { // if valid pulse-width range
-        ppmInValid = 100;
+        ppmInValid = PPM_IN_VALID_TIMEOUT;
         g_ppmIns[ppmInState++ - 1] = (int16_t)(val - 1500) * (uint8_t)(g_eeGeneral.PPM_Multiplier+10)/10; //+-500 != 512, but close enough.
       }
       else {
diff --git a/radio/src/opentx.h b/radio/src/opentx.h
index c4786ba0a..d7af3bec1 100644
--- a/radio/src/opentx.h
+++ b/radio/src/opentx.h
@@ -1123,6 +1123,7 @@ extern uint8_t            g_beepVal[5];
 
 extern uint8_t            ppmInState; //0=unsync 1..8= wait for value i-1
 extern uint8_t            ppmInValid;
+#define PPM_IN_VALID_TIMEOUT 100
 extern int16_t            g_ppmIns[NUM_TRAINER];
 extern int32_t            chans[NUM_CHNOUT];
 extern int16_t            ex_chans[NUM_CHNOUT]; // Outputs (before LIMITS) of the last perMain
diff --git a/radio/src/sbus.cpp b/radio/src/sbus.cpp
index 086659833..2d8879f52 100755
--- a/radio/src/sbus.cpp
+++ b/radio/src/sbus.cpp
@@ -36,7 +36,7 @@
 
 #include "opentx.h"
 
-Fifo<28> sbusFifo;
+Fifo<32> sbusFifo;
 uint8_t SbusFrame[28] ;
 uint16_t SbusTimer ;
 uint8_t SbusIndex = 0 ;
@@ -59,6 +59,8 @@ void processSbusFrame(uint8_t *sbus, int16_t *pulses)
     inputbitsavailable -= 11;
     inputbits >>= 11;
   }
+
+  ppmInValid = PPM_IN_VALID_TIMEOUT;
 }
 
 #define SBUS_DELAY 1000 // 500uS
diff --git a/radio/src/targets/simu/simpgmspace.h b/radio/src/targets/simu/simpgmspace.h
index f4c34239b..162fafef2 100644
--- a/radio/src/targets/simu/simpgmspace.h
+++ b/radio/src/targets/simu/simpgmspace.h
@@ -406,6 +406,7 @@ inline void GPIO_Init(GPIO_TypeDef* GPIOx, GPIO_InitTypeDef* GPIO_InitStruct) {
 #define GPIO_ResetBits(GPIOx, pin) GPIOx->BSRRL &= ~pin
 #define GPIO_ReadInputDataBit(GPIOx, pin) (GPIOx->BSRRL & pin)
 #define RCC_AHB1PeriphClockCmd(...)
+#define RCC_APB2PeriphClockCmd(...)
 #endif
 
 #define configure_pins(...)
diff --git a/radio/src/targets/sky9x/board_sky9x.cpp b/radio/src/targets/sky9x/board_sky9x.cpp
index 93d3fa4d7..42d283499 100644
--- a/radio/src/targets/sky9x/board_sky9x.cpp
+++ b/radio/src/targets/sky9x/board_sky9x.cpp
@@ -257,7 +257,7 @@ extern "C" void TC3_IRQHandler() //capture ppm in at 2MHz
   else {
     if (ppmInState>0 && ppmInState<=16) {
       if (val>800 && val<2200) { // if valid pulse-width range
-        ppmInValid = 100;
+        ppmInValid = PPM_IN_VALID_TIMEOUT;
         g_ppmIns[ppmInState++ - 1] = (int16_t)(val - 1500)*(g_eeGeneral.PPM_Multiplier+10)/10; //+-500 != 512, but close enough.
       }
       else {
diff --git a/radio/src/targets/taranis/board_taranis.h b/radio/src/targets/taranis/board_taranis.h
index 2c7df163e..5d6f2d0bd 100644
--- a/radio/src/targets/taranis/board_taranis.h
+++ b/radio/src/targets/taranis/board_taranis.h
@@ -263,7 +263,10 @@ void hapticOff(void);
 void uart3Init(unsigned int mode, unsigned int protocol);
 void uart3Putc(const char c);
 #define telemetrySecondPortInit(protocol) uart3Init(UART_MODE_TELEMETRY, protocol)
-void uart3SbusInit();
-void uart3Stop();
+void uart3SbusInit(void);
+void uart3Stop(void);
+
+#define USART_FLAG_ERRORS (USART_FLAG_ORE | USART_FLAG_NE | USART_FLAG_FE | USART_FLAG_PE)
+
 
 #endif
diff --git a/radio/src/targets/taranis/trainer_driver.cpp b/radio/src/targets/taranis/trainer_driver.cpp
index 51336cf6d..2167f636f 100644
--- a/radio/src/targets/taranis/trainer_driver.cpp
+++ b/radio/src/targets/taranis/trainer_driver.cpp
@@ -38,7 +38,7 @@
 
 uint16_t * TrainerPulsePtr;
 extern uint16_t ppmStream[NUM_MODULES+1][20];
-extern Fifo<28> sbusFifo;
+extern Fifo<32> sbusFifo;
 
 #define setupTrainerPulses() setupPulsesPPM(TRAINER_MODULE)
 
@@ -141,7 +141,7 @@ extern "C" void TIM3_IRQHandler()
     else {
       if (ppmInState>0 && ppmInState<=16) {
         if (val>800 && val<2200) {
-          ppmInValid = 100;
+          ppmInValid = PPM_IN_VALID_TIMEOUT;
           g_ppmIns[ppmInState++ - 1] = (int16_t)(val - 1500)*(g_eeGeneral.PPM_Multiplier+10)/10; //+-500 != 512, but close enough.
         }
         else {
@@ -208,21 +208,41 @@ void stop_cppm_on_heartbeat_capture(void)
   }
 }
 
-void init_sbus_on_heartbeat_capture(void)
+void init_sbus_on_heartbeat_capture()
 {
   EXTERNAL_MODULE_ON();
 
-  RCC->APB2ENR |= RCC_APB2ENR_USART6EN ;          // Enable clock
-  RCC->AHB1ENR |= RCC_AHB1ENR_GPIOCEN ;           // Enable portC clock
-  // GPIOC->MODER = (GPIOC->MODER & 0xFFFFBFFF ) | 0x00008000 ;      // Alternate func.
-  // GPIOC->AFR[0] = (GPIOC->AFR[0] & 0x0FFFFFFF ) | 0x80000000 ;    // Alternate func.
-  configure_pins( 0x0080, PIN_PERIPHERAL | PIN_PORTC | PIN_PER_8 ) ;
-  USART6->BRR = PERI2_FREQUENCY / 100000 ;
-  USART6->CR1 = USART_CR1_UE | USART_CR1_RXNEIE | USART_CR1_RE | USART_CR1_M | USART_CR1_PCE ;
-  USART6->CR2 = 0 ;
-  USART6->CR3 = 0 ;
-  (void) USART6->DR ;
-  NVIC_EnableIRQ(USART6_IRQn) ;
+  USART_InitTypeDef USART_InitStructure;
+  GPIO_InitTypeDef GPIO_InitStructure;
+
+  RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOC, ENABLE);
+
+  GPIO_PinAFConfig(GPIOC, GPIO_PinSource7, GPIO_AF_USART6);
+
+  GPIO_InitStructure.GPIO_Pin = GPIO_Pin_7;
+  GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF;
+  GPIO_InitStructure.GPIO_OType = GPIO_OType_PP;
+  GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_UP;
+  GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
+  GPIO_Init(GPIOC, &GPIO_InitStructure);
+
+  RCC_APB2PeriphClockCmd(RCC_APB2Periph_USART6, ENABLE);
+
+  USART_InitStructure.USART_BaudRate = 100000;
+  USART_InitStructure.USART_WordLength = USART_WordLength_9b;
+  USART_InitStructure.USART_StopBits = USART_StopBits_1;
+  USART_InitStructure.USART_Parity = USART_Parity_Even;
+  USART_InitStructure.USART_HardwareFlowControl = USART_HardwareFlowControl_None;
+  USART_InitStructure.USART_Mode = USART_Mode_Rx;
+
+  USART_Init(USART6, &USART_InitStructure);
+
+  USART_Cmd(USART6, ENABLE);
+
+  USART_ITConfig(USART6, USART_IT_RXNE, ENABLE);
+
+  NVIC_SetPriority(USART6_IRQn, 7);
+  NVIC_EnableIRQ(USART6_IRQn);
 }
 
 void stop_sbus_on_heartbeat_capture(void)
diff --git a/radio/src/targets/taranis/uart3_driver.cpp b/radio/src/targets/taranis/uart3_driver.cpp
index 2a30bd6d4..08a4fbe96 100644
--- a/radio/src/targets/taranis/uart3_driver.cpp
+++ b/radio/src/targets/taranis/uart3_driver.cpp
@@ -39,7 +39,7 @@
 uint8_t uart3Mode = UART_MODE_NONE;
 Fifo<512> uart3TxFifo;
 extern Fifo<512> telemetryFifo;
-extern Fifo<28> sbusFifo;
+extern Fifo<32> sbusFifo;
 
 void uart3Setup(unsigned int baudrate)
 {
@@ -73,8 +73,8 @@ void uart3Setup(unsigned int baudrate)
   USART_ITConfig(UART3, USART_IT_RXNE, DISABLE);
   USART_ITConfig(UART3, USART_IT_TXE, DISABLE);
 
-  NVIC_EnableIRQ(USART3_IRQn);
   NVIC_SetPriority(USART3_IRQn, 7);
+  NVIC_EnableIRQ(USART3_IRQn);
 }
 
 void uart3Init(unsigned int mode, unsigned int protocol)
@@ -128,8 +128,6 @@ void uart3Stop()
   USART_DeInit(USART3);
 }
 
-#define USART_FLAG_ERRORS (USART_FLAG_ORE | USART_FLAG_NE | USART_FLAG_FE | USART_FLAG_PE)
-
 extern "C" void USART3_IRQHandler(void)
 {
   // Send