diff --git a/radio/src/targets/common/arm/stm32/extmodule_driver.cpp b/radio/src/targets/common/arm/stm32/extmodule_driver.cpp
index 2c0d6fdd3..daf9e5238 100644
--- a/radio/src/targets/common/arm/stm32/extmodule_driver.cpp
+++ b/radio/src/targets/common/arm/stm32/extmodule_driver.cpp
@@ -25,12 +25,6 @@
 #include "hal.h"
 #include "timers_driver.h"
 
-#if defined(CROSSFIRE)
-#include "pulses/crossfire.h"
-#endif
-
-#define STOP_TIMER_ON_LAST_UPDATE
-
 static const stm32_pulse_timer_t extmoduleTimer = {
   .GPIOx = EXTMODULE_TX_GPIO,
   .GPIO_Pin = EXTMODULE_TX_GPIO_PIN,
@@ -45,53 +39,23 @@ static const stm32_pulse_timer_t extmoduleTimer = {
   .DMA_IRQn = EXTMODULE_TIMER_DMA_STREAM_IRQn,
 };
 
-#if defined(STOP_TIMER_ON_LAST_UPDATE)
-
-static_assert(EXTMODULE_TIMER_Channel == LL_TIM_CHANNEL_CH1
-              || EXTMODULE_TIMER_Channel == LL_TIM_CHANNEL_CH1N
-              || EXTMODULE_TIMER_Channel == LL_TIM_CHANNEL_CH3,
+// Make sure the timer channel is supported
+static_assert(__STM32_PULSE_IS_TIMER_CHANNEL_SUPPORTED(EXTMODULE_TIMER_Channel),
               "Unsupported timer channel");
 
-static void set_compare_reg(uint32_t val)
-{
-  switch(EXTMODULE_TIMER_Channel){
-  case LL_TIM_CHANNEL_CH1:
-  case LL_TIM_CHANNEL_CH1N:
-    LL_TIM_OC_SetCompareCH1(EXTMODULE_TIMER, val);
-    break;
-  case LL_TIM_CHANNEL_CH3:
-    LL_TIM_OC_SetCompareCH3(EXTMODULE_TIMER, val);
-    break;
-  }
-}
+// Make sure the DMA channel is supported
+static_assert(__STM32_PULSE_IS_DMA_STREAM_SUPPORTED(EXTMODULE_TIMER_DMA_STREAM_LL),
+              "Unsupported DMA stream");
 
 extern "C" void EXTMODULE_TIMER_DMA_IRQHandler()
 {
-  if (!LL_DMA_IsActiveFlag_TC5(EXTMODULE_TIMER_DMA))
-    return;
-  
-  LL_DMA_ClearFlag_TC5(EXTMODULE_TIMER_DMA);
-
-  LL_TIM_ClearFlag_UPDATE(EXTMODULE_TIMER);
-  LL_TIM_EnableIT_UPDATE(EXTMODULE_TIMER);
-
-  set_compare_reg(0);
-  LL_TIM_OC_SetMode(EXTMODULE_TIMER, EXTMODULE_TIMER_Channel, LL_TIM_OCMODE_PWM1);
+  stm32_pulse_dma_tc_isr(&extmoduleTimer);
 }
 
 extern "C" void EXTMODULE_TIMER_IRQHandler()
 {
-  if (!LL_TIM_IsActiveFlag_UPDATE(EXTMODULE_TIMER))
-    return;
-
-  LL_TIM_ClearFlag_UPDATE(EXTMODULE_TIMER);
-  LL_TIM_DisableIT_UPDATE(EXTMODULE_TIMER);
-
-  // Halt pulses and force to inactive level
-  LL_TIM_OC_SetMode(EXTMODULE_TIMER, EXTMODULE_TIMER_Channel,
-                    LL_TIM_OCMODE_FORCED_INACTIVE);
+  stm32_pulse_tim_update_isr(&extmoduleTimer);
 }
-#endif
 
 void extmoduleStop()
 {
@@ -135,23 +99,15 @@ void extmodulePpmStart(uint16_t ppm_delay, bool polarity)
 void extmoduleSendNextFramePpm(void* pulses, uint16_t length,
                                uint16_t ppm_delay, bool polarity)
 {
-  if (!stm32_pulse_stop_if_running(&extmoduleTimer))
+  if (!stm32_pulse_if_not_running_disable(&extmoduleTimer))
     return;
 
-  // Config output
-  set_compare_reg(ppm_delay * 2);
- 
-  uint32_t ll_polarity;
-  if (polarity) {
-    ll_polarity = LL_TIM_OCPOLARITY_LOW;
-  } else {
-    ll_polarity = LL_TIM_OCPOLARITY_HIGH;
-  }
-  LL_TIM_OC_SetPolarity(EXTMODULE_TIMER, EXTMODULE_TIMER_Channel, ll_polarity);
-  LL_TIM_OC_SetMode(EXTMODULE_TIMER, EXTMODULE_TIMER_Channel, LL_TIM_OCMODE_PWM1);
+  // Set polarity
+  stm32_pulse_set_polarity(&extmoduleTimer, !polarity);
 
   // Start DMA request and re-enable timer
-  stm32_pulse_start_dma_req(&extmoduleTimer, pulses, length);
+  stm32_pulse_start_dma_req(&extmoduleTimer, pulses, length,
+                            LL_TIM_OCMODE_PWM1, ppm_delay * 2);
 }
 
 #if defined(PXX1)
@@ -174,14 +130,12 @@ void extmodulePxx1PulsesStart()
 
 void extmoduleSendNextFramePxx1(const void* pulses, uint16_t length)
 {
-  if (!stm32_pulse_stop_if_running(&extmoduleTimer))
+  if (!stm32_pulse_if_not_running_disable(&extmoduleTimer))
     return;
 
-  set_compare_reg(9 * 2);
-  LL_TIM_OC_SetMode(EXTMODULE_TIMER, EXTMODULE_TIMER_Channel, LL_TIM_OCMODE_PWM1);
-
   // Start DMA request and re-enable timer
-  stm32_pulse_start_dma_req(&extmoduleTimer, pulses, length);
+  stm32_pulse_start_dma_req(&extmoduleTimer, pulses, length,
+                            LL_TIM_OCMODE_PWM1, 9 * 2);
 }
 #endif
 
@@ -204,20 +158,14 @@ void extmoduleSerialStart()
 
 void extmoduleSendNextFrameSoftSerial(const void* pulses, uint16_t length, bool polarity)
 {
-  if (!stm32_pulse_stop_if_running(&extmoduleTimer))
+  if (!stm32_pulse_if_not_running_disable(&extmoduleTimer))
     return;
 
-  uint32_t ll_polarity;
-  if (polarity) {
-    ll_polarity = LL_TIM_OCPOLARITY_HIGH;
-  } else {
-    ll_polarity = LL_TIM_OCPOLARITY_LOW;
-  }
-  LL_TIM_OC_SetPolarity(EXTMODULE_TIMER, EXTMODULE_TIMER_Channel, ll_polarity);
-  LL_TIM_OC_SetMode(EXTMODULE_TIMER, EXTMODULE_TIMER_Channel, LL_TIM_OCMODE_TOGGLE);
-
+  // Set polarity
+  stm32_pulse_set_polarity(&extmoduleTimer, polarity);
+  
   // Start DMA request and re-enable timer
-  stm32_pulse_start_dma_req(&extmoduleTimer, pulses, length);
+  stm32_pulse_start_dma_req(&extmoduleTimer, pulses, length, LL_TIM_OCMODE_TOGGLE, 0);
 }
 
 // Delay based byte sending @ 57600 bps
diff --git a/radio/src/targets/common/arm/stm32/stm32_pulse_driver.cpp b/radio/src/targets/common/arm/stm32/stm32_pulse_driver.cpp
index 207f5cb49..6dbb5bde0 100644
--- a/radio/src/targets/common/arm/stm32/stm32_pulse_driver.cpp
+++ b/radio/src/targets/common/arm/stm32/stm32_pulse_driver.cpp
@@ -22,8 +22,6 @@
 #include "stm32_pulse_driver.h"
 #include "definitions.h"
 
-#define STOP_TIMER_ON_LAST_UPDATE
-
 void stm32_pulse_init(const stm32_pulse_timer_t* tim)
 {
   LL_GPIO_InitTypeDef pinInit;
@@ -41,7 +39,6 @@ void stm32_pulse_init(const stm32_pulse_timer_t* tim)
   timInit.Autoreload = 65535;
   LL_TIM_Init(tim->TIMx, &timInit);
 
-#if defined(STOP_TIMER_ON_LAST_UPDATE)
   // Enable DMA IRQ
   NVIC_EnableIRQ(tim->DMA_IRQn);
   NVIC_SetPriority(tim->DMA_IRQn, 7);
@@ -49,11 +46,14 @@ void stm32_pulse_init(const stm32_pulse_timer_t* tim)
   // Enable timer IRQ
   NVIC_EnableIRQ(tim->TIM_IRQn);
   NVIC_SetPriority(tim->TIM_IRQn, 7);
-#endif
 }
 
 void stm32_pulse_deinit(const stm32_pulse_timer_t* tim)
 {
+  // Disable IRQs
+  NVIC_DisableIRQ(tim->DMA_IRQn);
+  NVIC_DisableIRQ(tim->TIM_IRQn);
+  
   // De-init DMA & timer
   LL_DMA_DeInit(tim->DMAx, tim->DMA_Stream);
   LL_TIM_DeInit(tim->TIMx);
@@ -79,8 +79,19 @@ void stm32_pulse_config_output(const stm32_pulse_timer_t* tim, LL_TIM_OC_InitTyp
   LL_TIM_EnableDMAReq_UPDATE(tim->TIMx);
 }
 
+void stm32_pulse_set_polarity(const stm32_pulse_timer_t* tim, bool polarity)
+{
+  uint32_t ll_polarity;
+  if (polarity) {
+    ll_polarity = LL_TIM_OCPOLARITY_HIGH;
+  } else {
+    ll_polarity = LL_TIM_OCPOLARITY_LOW;
+  }
+  LL_TIM_OC_SetPolarity(tim->TIMx, tim->TIM_Channel, ll_polarity);  
+}
+
 // return true if stopped, false otherwise
-bool stm32_pulse_stop_if_running(const stm32_pulse_timer_t* tim)
+bool stm32_pulse_if_not_running_disable(const stm32_pulse_timer_t* tim)
 {
   if (LL_DMA_IsEnabledStream(tim->DMAx, tim->DMA_Stream))
     return false;
@@ -92,8 +103,22 @@ bool stm32_pulse_stop_if_running(const stm32_pulse_timer_t* tim)
   return true;
 }
 
+static void set_compare_reg(const stm32_pulse_timer_t* tim, uint32_t val)
+{
+  switch(tim->TIM_Channel){
+  case LL_TIM_CHANNEL_CH1:
+  case LL_TIM_CHANNEL_CH1N:
+    LL_TIM_OC_SetCompareCH1(tim->TIMx, val);
+    break;
+  case LL_TIM_CHANNEL_CH3:
+    LL_TIM_OC_SetCompareCH3(tim->TIMx, val);
+    break;
+  }
+}
+
 void stm32_pulse_start_dma_req(const stm32_pulse_timer_t* tim,
-                               const void* pulses, uint16_t length)
+                               const void* pulses, uint16_t length,
+                               uint32_t ocmode, uint32_t cmp_val)
 {
   // re-init DMA stream
   LL_DMA_DeInit(tim->DMAx, tim->DMA_Stream);
@@ -128,10 +153,8 @@ void stm32_pulse_start_dma_req(const stm32_pulse_timer_t* tim,
 
   LL_DMA_Init(tim->DMAx, tim->DMA_Stream, &dmaInit);
 
-#if defined(STOP_TIMER_ON_LAST_UPDATE)
   // Enable TC IRQ
   LL_DMA_EnableIT_TC(tim->DMAx, tim->DMA_Stream);
-#endif
 
   // Enable DMA
   LL_TIM_ClearFlag_UPDATE(tim->TIMx);
@@ -139,6 +162,10 @@ void stm32_pulse_start_dma_req(const stm32_pulse_timer_t* tim,
   LL_TIM_SetCounter(tim->TIMx, 0);
   LL_DMA_EnableStream(tim->DMAx, tim->DMA_Stream);
 
+  // Re-configure timer output
+  set_compare_reg(tim, cmp_val);
+  LL_TIM_OC_SetMode(tim->TIMx, tim->TIM_Channel, ocmode);
+  
   // Trigger update to effect the first DMA transation
   // and thus load ARR with the first duration
   LL_TIM_EnableDMAReq_UPDATE(tim->TIMx);
@@ -147,3 +174,45 @@ void stm32_pulse_start_dma_req(const stm32_pulse_timer_t* tim,
   // start timer
   LL_TIM_EnableCounter(tim->TIMx);
 }
+
+static bool check_and_clean_dma_tc_flag(const stm32_pulse_timer_t* tim)
+{
+  switch(tim->DMA_Stream) {
+  case LL_DMA_STREAM_1:
+    if (!LL_DMA_IsActiveFlag_TC1(tim->DMAx)) return false;
+    LL_DMA_ClearFlag_TC1(tim->DMAx);
+    break;
+  case LL_DMA_STREAM_5:
+    if (!LL_DMA_IsActiveFlag_TC5(tim->DMAx)) return false;
+    LL_DMA_ClearFlag_TC5(tim->DMAx);
+    break;
+  case LL_DMA_STREAM_7:
+    if (!LL_DMA_IsActiveFlag_TC7(tim->DMAx)) return false;
+    LL_DMA_ClearFlag_TC7(tim->DMAx);
+    break;
+  }
+  return true;
+}
+
+void stm32_pulse_dma_tc_isr(const stm32_pulse_timer_t* tim)
+{
+  if (!check_and_clean_dma_tc_flag(tim)) return;
+
+  LL_TIM_ClearFlag_UPDATE(tim->TIMx);
+  LL_TIM_EnableIT_UPDATE(tim->TIMx);
+
+  set_compare_reg(tim, 0);
+  LL_TIM_OC_SetMode(tim->TIMx, tim->TIM_Channel, LL_TIM_OCMODE_PWM1);
+}
+
+void stm32_pulse_tim_update_isr(const stm32_pulse_timer_t* tim)
+{
+  if (!LL_TIM_IsActiveFlag_UPDATE(tim->TIMx))
+    return;
+
+  LL_TIM_ClearFlag_UPDATE(tim->TIMx);
+  LL_TIM_DisableIT_UPDATE(tim->TIMx);
+
+  // Halt pulses by forcing to inactive level
+  LL_TIM_OC_SetMode(tim->TIMx, tim->TIM_Channel, LL_TIM_OCMODE_FORCED_INACTIVE);
+}
diff --git a/radio/src/targets/common/arm/stm32/stm32_pulse_driver.h b/radio/src/targets/common/arm/stm32/stm32_pulse_driver.h
index e97df6124..cce089da8 100644
--- a/radio/src/targets/common/arm/stm32/stm32_pulse_driver.h
+++ b/radio/src/targets/common/arm/stm32/stm32_pulse_driver.h
@@ -44,9 +44,25 @@ struct stm32_pulse_timer_t {
 void stm32_pulse_init(const stm32_pulse_timer_t* tim);
 void stm32_pulse_deinit(const stm32_pulse_timer_t* tim);
 void stm32_pulse_config_output(const stm32_pulse_timer_t* tim, LL_TIM_OC_InitTypeDef* ocInit);
+void stm32_pulse_set_polarity(const stm32_pulse_timer_t* tim, bool polarity);
 
-// return true if stopped, false otherwise
-bool stm32_pulse_stop_if_running(const stm32_pulse_timer_t* tim);
+// return true if it could be disabled without interrupting a pulse train, false otherwise
+bool stm32_pulse_if_not_running_disable(const stm32_pulse_timer_t* tim);
 
 void stm32_pulse_start_dma_req(const stm32_pulse_timer_t* tim,
-                               const void* pulses, uint16_t length);
+                               const void* pulses, uint16_t length,
+                               uint32_t ocmode, uint32_t cmp_val);
+
+// Must be called from DMA TC IRQ handler
+void stm32_pulse_dma_tc_isr(const stm32_pulse_timer_t* tim);
+
+// Must be called from timer UPDATE IRQ handler
+void stm32_pulse_tim_update_isr(const stm32_pulse_timer_t* tim);
+
+#define __STM32_PULSE_IS_TIMER_CHANNEL_SUPPORTED(ch)       \
+  ((ch) == LL_TIM_CHANNEL_CH1 || (ch) == LL_TIM_CHANNEL_CH1N || \
+   (ch) == LL_TIM_CHANNEL_CH3)
+
+#define __STM32_PULSE_IS_DMA_STREAM_SUPPORTED(stream)       \
+  ((stream) == LL_DMA_STREAM_1 || (stream) == LL_DMA_STREAM_5 || \
+   (stream) == LL_DMA_STREAM_7)