diff --git a/radio/src/mixer_scheduler.h b/radio/src/mixer_scheduler.h
index 768a38507..afc96d8cc 100644
--- a/radio/src/mixer_scheduler.h
+++ b/radio/src/mixer_scheduler.h
@@ -19,8 +19,9 @@
  * GNU General Public License for more details.
  */
 
-#ifndef _MIXER_SCHEDULER_H_
-#define _MIXER_SCHEDULER_H_
+#pragma once
+
+#include <stdint.h>
 
 #define MIXER_SCHEDULER_DEFAULT_PERIOD_US  4000u // 4ms
 #define MIXER_SCHEDULER_JOYSTICK_PERIOD_US 2000u // 2ms
@@ -85,5 +86,3 @@ static inline bool mixerSchedulerWaitForTrigger(uint8_t timeout)
 #define mixerSchedulerISRTrigger()
 
 #endif
-
-#endif
diff --git a/radio/src/pulses/pulses.cpp b/radio/src/pulses/pulses.cpp
index 44f5bdf52..dd1ae356c 100755
--- a/radio/src/pulses/pulses.cpp
+++ b/radio/src/pulses/pulses.cpp
@@ -33,6 +33,7 @@
 #include "intmodule_pulses_driver.h"
 #endif
 
+#include "extmodule_serial_driver.h"
 #include "extmodule_driver.h"
 
 #if defined(CROSSFIRE)
@@ -720,8 +721,8 @@ void extmoduleSendNextFrame()
 
 #if defined(PXX1) && defined(HARDWARE_EXTERNAL_MODULE_SIZE_SML)
     case PROTOCOL_CHANNELS_PXX1_SERIAL:
-      extmoduleSendBuffer(extmodulePulsesData.pxx_uart.getData(),
-                          extmodulePulsesData.pxx_uart.getSize());
+      ExtmoduleSerialDriver.sendBuffer(extmodulePulsesData.pxx_uart.getData(),
+                                       extmodulePulsesData.pxx_uart.getSize());
       break;
 #endif
 
diff --git a/radio/src/targets/common/arm/stm32/heartbeat_driver.cpp b/radio/src/targets/common/arm/stm32/heartbeat_driver.cpp
index 56b93b1a0..bba0f6106 100644
--- a/radio/src/targets/common/arm/stm32/heartbeat_driver.cpp
+++ b/radio/src/targets/common/arm/stm32/heartbeat_driver.cpp
@@ -19,8 +19,8 @@
  * GNU General Public License for more details.
  */
 
-#include "opentx.h"
 #include "mixer_scheduler.h"
+#include "board.h"
 
 #if defined(INTMODULE_HEARTBEAT_GPIO)
 
diff --git a/radio/src/targets/taranis/CMakeLists.txt b/radio/src/targets/taranis/CMakeLists.txt
index 4cb342fcd..b7a15b978 100644
--- a/radio/src/targets/taranis/CMakeLists.txt
+++ b/radio/src/targets/taranis/CMakeLists.txt
@@ -548,7 +548,6 @@ set(FIRMWARE_TARGET_SRC
   board.cpp
   i2c_driver.cpp
   ../common/arm/stm32/pwr_driver.cpp
-  ../common/arm/stm32/heartbeat_driver.cpp
   ../common/arm/loadboot.cpp
   )
 
diff --git a/radio/src/trainer.cpp b/radio/src/trainer.cpp
index 8b88a57df..651cf4031 100644
--- a/radio/src/trainer.cpp
+++ b/radio/src/trainer.cpp
@@ -141,18 +141,23 @@ void checkTrainerSettings()
         break;
     }
 
+#if defined(INTMODULE_HEARTBEAT_GPIO)
 #if defined(TRAINER_MODULE_CPPM) || defined(TRAINER_MODULE_SBUS)
-    if (requiredTrainerMode == TRAINER_MODE_MASTER_CPPM_EXTERNAL_MODULE || requiredTrainerMode == TRAINER_MODE_MASTER_SBUS_EXTERNAL_MODULE)
+    if (requiredTrainerMode == TRAINER_MODE_MASTER_CPPM_EXTERNAL_MODULE ||
+        requiredTrainerMode == TRAINER_MODE_MASTER_SBUS_EXTERNAL_MODULE)
       stop_intmodule_heartbeat();
     else
       init_intmodule_heartbeat();
 #else
 #if defined(HARDWARE_EXTERNAL_ACCESS_MOD)
-    if (g_model.moduleData[EXTERNAL_MODULE].type != MODULE_TYPE_R9M_PXX2) // externalaccessmod 'bridges' HB and Ext module RX pins
+    if (g_model.moduleData[EXTERNAL_MODULE].type !=
+        MODULE_TYPE_R9M_PXX2)  // externalaccessmod 'bridges' HB and Ext module
+                               // RX pins
       init_intmodule_heartbeat();
 #elif defined(INTMODULE_HEARTBEAT_GPIO)
     init_intmodule_heartbeat();
 #endif
 #endif
+#endif // INTMODULE_HEARTBEAT_GPIO
   }
 }