diff --git a/radio/src/cli.cpp b/radio/src/cli.cpp
index d3a7e2b2d..867feb747 100644
--- a/radio/src/cli.cpp
+++ b/radio/src/cli.cpp
@@ -1143,7 +1143,7 @@ int cliSerialPassthrough(const char **argv)
       while (cdcConnected) {
 
         uint8_t data;
-        if (intmoduleFifo.pop(data)) {
+        if (IntmoduleSerialDriver.getByte(uart_ctx, &data) > 0) {
 
           uint8_t timeout = 10; // 10 ms
           while(!usbSerialFreeSpace() && (timeout > 0)) {
diff --git a/radio/src/dmafifo.h b/radio/src/dmafifo.h
index db0d885d5..837dfd2da 100644
--- a/radio/src/dmafifo.h
+++ b/radio/src/dmafifo.h
@@ -36,7 +36,7 @@ class DMAFifo
 
     void clear()
     {
-      ridx = 0;
+      ridx = N - stream->NDTR;
     }
 
     uint32_t size()
diff --git a/radio/src/fifo.h b/radio/src/fifo.h
index 283a21a6f..0e1b93617 100644
--- a/radio/src/fifo.h
+++ b/radio/src/fifo.h
@@ -99,6 +99,11 @@ class Fifo
       }
     }
 
+    T * buffer()
+    {
+      return fifo;
+    }
+
   protected:
     T fifo[N];
     volatile uint32_t widx;
diff --git a/radio/src/hal/module_driver.h b/radio/src/hal/module_driver.h
index c4ab06535..6b5b21407 100644
--- a/radio/src/hal/module_driver.h
+++ b/radio/src/hal/module_driver.h
@@ -62,5 +62,8 @@ struct etx_module_driver_t {
 
     // Send the pulses
     void (*sendPulses)(void* context);
+
+    // Fetch telemetry byte
+    int (*getByte)(void* context, uint8_t* data);
 };
 
diff --git a/radio/src/hal/serial_driver.h b/radio/src/hal/serial_driver.h
index 3ebc84b50..a27f0405c 100644
--- a/radio/src/hal/serial_driver.h
+++ b/radio/src/hal/serial_driver.h
@@ -75,6 +75,9 @@ typedef struct {
   // Fetch byte from internal buffer
   int (*getByte)(void* ctx, uint8_t* data);
 
+  // Clear internal buffer
+  void (*clearRxBuffer)(void* ctx);
+
   // Get current baudrate
   uint32_t (*getBaudrate)(void*);
   
diff --git a/radio/src/io/frsky_firmware_update.cpp b/radio/src/io/frsky_firmware_update.cpp
index dca87330a..a6247790a 100644
--- a/radio/src/io/frsky_firmware_update.cpp
+++ b/radio/src/io/frsky_firmware_update.cpp
@@ -121,7 +121,7 @@ bool FrskyDeviceFirmwareUpdate::readBuffer(uint8_t * buffer, uint8_t count, uint
       uint32_t elapsed = 0;
       uint8_t index = 0;
       while (index < count && elapsed < timeout) {
-        if (intmoduleFifo.pop(buffer[index])) {
+        if (IntmoduleSerialDriver.getByte(uart_ctx, &(buffer[index]))) {
           ++index;
         }
         else {
@@ -141,14 +141,15 @@ bool FrskyDeviceFirmwareUpdate::readBuffer(uint8_t * buffer, uint8_t count, uint
 }
 #endif
 
-const uint8_t * FrskyDeviceFirmwareUpdate::readFullDuplexFrame(ModuleFifo & fifo, uint32_t timeout)
+const uint8_t * FrskyDeviceFirmwareUpdate::readFullDuplexFrame(uint32_t timeout)
 {
+#if defined(INTMODULE_USART)
   uint8_t len = 0;
   bool bytestuff = false;
   while (len < 10) {
     uint32_t elapsed = 0;
-    uint8_t byte;
-    while (!fifo.pop(byte)) {
+    uint8_t byte = 0;
+    while (IntmoduleSerialDriver.getByte(uart_ctx, &byte) == 0) {
       RTOS_WAIT_MS(1);
       if (elapsed++ >= timeout) {
         return nullptr;
@@ -170,6 +171,9 @@ const uint8_t * FrskyDeviceFirmwareUpdate::readFullDuplexFrame(ModuleFifo & fifo
     }
   }
   return &frame[1];
+#else
+  return nullptr;
+#endif
 }
 
 const uint8_t * FrskyDeviceFirmwareUpdate::readHalfDuplexFrame(uint32_t timeout)
@@ -193,7 +197,7 @@ const uint8_t * FrskyDeviceFirmwareUpdate::readFrame(uint32_t timeout)
   switch (module) {
 #if defined(INTERNAL_MODULE_PXX2)
     case INTERNAL_MODULE:
-      return readFullDuplexFrame(intmoduleFifo, timeout);
+      return readFullDuplexFrame(timeout);
 #endif
 
     default:
diff --git a/radio/src/io/frsky_firmware_update.h b/radio/src/io/frsky_firmware_update.h
index 5fa129c29..288811303 100644
--- a/radio/src/io/frsky_firmware_update.h
+++ b/radio/src/io/frsky_firmware_update.h
@@ -24,10 +24,6 @@
 
 #include "dataconstants.h"
 #include "definitions.h"
-#include "frsky_pxx2.h"
-#include "pulses/modules_helpers.h"
-#include "ff.h"
-#include "popups.h"
 
 enum FrskyFirmwareProductFamily {
   FIRMWARE_FAMILY_INTERNAL_MODULE,
@@ -143,7 +139,7 @@ class FrskyDeviceFirmwareUpdate {
     void sendFrame();
 
     bool readBuffer(uint8_t * buffer, uint8_t count, uint32_t timeout);
-    const uint8_t * readFullDuplexFrame(ModuleFifo & fifo, uint32_t timeout);
+    const uint8_t * readFullDuplexFrame(uint32_t timeout);
     const uint8_t * readHalfDuplexFrame(uint32_t timeout);
     const uint8_t * readFrame(uint32_t timeout);
     bool waitState(State state, uint32_t timeout);
diff --git a/radio/src/io/frsky_pxx2.h b/radio/src/io/frsky_pxx2.h
deleted file mode 100644
index e48d99a9f..000000000
--- a/radio/src/io/frsky_pxx2.h
+++ /dev/null
@@ -1,81 +0,0 @@
-/*
- * Copyright (C) EdgeTX
- *
- * Based on code named
- *   opentx - https://github.com/opentx/opentx
- *   th9x - http://code.google.com/p/th9x
- *   er9x - http://code.google.com/p/er9x
- *   gruvin9x - http://code.google.com/p/gruvin9x
- *
- * License GPLv2: http://www.gnu.org/licenses/gpl-2.0.html
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License version 2 as
- * published by the Free Software Foundation.
- *
- * This program 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.
- */
-
-#ifndef _IO_PXX2_H_
-#define _IO_PXX2_H_
-
-#include "fifo.h"
-#include "pulses/pxx.h"
-
-#include "board.h"
-
-class ModuleFifo : public Fifo<uint8_t, INTMODULE_FIFO_SIZE> {
-  public:
-    bool getFrame(uint8_t * frame)
-    {
-      while (true) {
-        if (isEmpty()) {
-          return false;
-        }
-        else if (fifo[ridx] != 0x7E) {
-          skip();
-        }
-        else {
-          break;
-        }
-      }
-
-      uint32_t next = nextIndex(ridx);
-      uint8_t len = fifo[next];
-
-      if (len > 40) {
-        clear();
-        return false;
-      }
-
-      if (size() < unsigned(len + 4 /* 2 bytes header + 2 bytes CRC */)) {
-        // frame not fully received
-        return false;
-      }
-
-      // we keep the length in frame[0]
-      frame[0] = fifo[next];
-      next = nextIndex(next);
-
-      uint16_t crc = 0xFFFF;
-
-      for (uint32_t i = 1; i <= len; i++) {
-        frame[i] = fifo[next];
-        crc -= frame[i];
-        next = nextIndex(next);
-      }
-
-      uint8_t crcLow = fifo[next];
-      next = nextIndex(next);
-      uint8_t crcHigh = fifo[next];
-      ridx = nextIndex(next);
-
-      return ((crc >> 8) == crcLow) && ((crc & 0xFF) == crcHigh);
-    }
-
-};
-
-#endif
diff --git a/radio/src/io/multi_firmware_update.cpp b/radio/src/io/multi_firmware_update.cpp
index f9f1faaef..ba4932728 100644
--- a/radio/src/io/multi_firmware_update.cpp
+++ b/radio/src/io/multi_firmware_update.cpp
@@ -106,7 +106,7 @@ class MultiInternalUpdateDriver: public MultiFirmwareUpdateDriver
 
     bool getByte(uint8_t & byte) const override
     {
-      return intmoduleFifo.pop(byte);
+      return IntmoduleSerialDriver.getByte(uart_ctx, &byte) > 0;
     }
 
     void sendByte(uint8_t byte) const override
@@ -116,7 +116,7 @@ class MultiInternalUpdateDriver: public MultiFirmwareUpdateDriver
 
     void clear() const override
     {
-      intmoduleFifo.clear();
+      IntmoduleSerialDriver.clearRxBuffer(uart_ctx);
     }
 
     void deinit(bool inverted) override
diff --git a/radio/src/pulses/afhds2.cpp b/radio/src/pulses/afhds2.cpp
index 7429b294f..3242e867d 100644
--- a/radio/src/pulses/afhds2.cpp
+++ b/radio/src/pulses/afhds2.cpp
@@ -19,16 +19,15 @@
  * GNU General Public License for more details.
  */
 
+#include "opentx.h"
 #include "afhds2.h"
 #include "flysky.h"
 
 #include "intmodule_serial_driver.h"
 #include "mixer_scheduler.h"
 
-// solely for 'intmoduleFifo'
-// TODO: remove this non-sense
-#include "opentx.h"
-#include "pulses/pxx2.h"
+#include "pulses/pulses.h"
+#include "telemetry/telemetry.h"
 
 afhds2::afhds2() {
   // TODO Auto-generated constructor stub
@@ -53,20 +52,18 @@ static void* afhds2Init(uint8_t module)
 
   // serial port setup
   resetPulsesAFHDS2();
-  intmoduleFifo.clear();
-  IntmoduleSerialDriver.init(&afhds2SerialInitParams);
+  void* ctx = IntmoduleSerialDriver.init(&afhds2SerialInitParams);
 
   // mixer setup
   mixerSchedulerSetPeriod(INTERNAL_MODULE, AFHDS2_PERIOD);
   INTERNAL_MODULE_ON();
 
-  return nullptr;
+  return ctx;
 }
 
 static void afhds2DeInit(void* context)
 {
   INTERNAL_MODULE_OFF();
-  intmoduleFifo.clear();
   IntmoduleSerialDriver.deinit(context);
 
   // mixer setup
@@ -96,10 +93,16 @@ static void afhds2SendPulses(void* context)
   IntmoduleSerialDriver.sendBuffer(context, data, size);
 }
 
+static int afhds2GetByte(void* context, uint8_t* data)
+{
+  return IntmoduleSerialDriver.getByte(context, data);
+}
+
 const etx_module_driver_t Afhds2InternalDriver = {
   .protocol = PROTOCOL_CHANNELS_AFHDS2A,
   .init = afhds2Init,
   .deinit = afhds2DeInit,
   .setupPulses = afhds2SetupPulses,
-  .sendPulses = afhds2SendPulses,    
+  .sendPulses = afhds2SendPulses,
+  .getByte = afhds2GetByte,
 };
diff --git a/radio/src/pulses/crossfire.cpp b/radio/src/pulses/crossfire.cpp
index 5bdb32707..2dc1c3b36 100644
--- a/radio/src/pulses/crossfire.cpp
+++ b/radio/src/pulses/crossfire.cpp
@@ -128,12 +128,9 @@ static void* crossfireInitInternal(uint8_t module)
   // serial port setup
   etx_serial_init params(intmoduleCrossfireInitParams);
   params.baudrate = INT_CROSSFIRE_BAUDRATE;
-
-  intmoduleFifo.clear();
-  IntmoduleSerialDriver.init(&params);
   INTERNAL_MODULE_ON();
 
-  return nullptr;
+  return IntmoduleSerialDriver.init(&params);
 }
 
 static void crossfireDeInitInternal(void* context)
@@ -143,7 +140,6 @@ static void crossfireDeInitInternal(void* context)
   INTERNAL_MODULE_OFF();
   mixerSchedulerSetPeriod(INTERNAL_MODULE, 0);
   intmoduleStop();
-  intmoduleFifo.clear();
 }
 
 static void crossfireSetupPulsesInternal(void* context, int16_t* channels, uint8_t nChannels)
@@ -159,12 +155,18 @@ static void crossfireSendPulsesInternal(void* context)
                                    intmodulePulsesData.crossfire.length);
 }
 
+static int crossfireGetByteInternal(void* context, uint8_t* data)
+{
+  return IntmoduleSerialDriver.getByte(context, data);
+}
+
 etx_module_driver_t CrossfireInternalDriver = {
   .protocol = PROTOCOL_CHANNELS_CROSSFIRE,
   .init = crossfireInitInternal,
   .deinit = crossfireDeInitInternal,
   .setupPulses = crossfireSetupPulsesInternal,
   .sendPulses = crossfireSendPulsesInternal,
+  .getByte = crossfireGetByteInternal,
 };
 #endif
 
diff --git a/radio/src/pulses/multi.cpp b/radio/src/pulses/multi.cpp
index 38e3f0a13..e4b6e6b4c 100644
--- a/radio/src/pulses/multi.cpp
+++ b/radio/src/pulses/multi.cpp
@@ -51,7 +51,7 @@ static void sendConfig(uint8_t moduleIdx);
 static void sendDSM(uint8_t moduleIdx);
 #endif
 
-#if defined(INTMODULE_USART)
+#if defined(INTMODULE_USART) && defined(INTERNAL_MODULE_MULTI)
 #include "intmodule_serial_driver.h"
 
 etx_serial_init multiSerialInitParams = {
@@ -65,7 +65,7 @@ etx_serial_init multiSerialInitParams = {
 
 static void sendMulti(uint8_t moduleIdx, uint8_t b)
 {
-#if defined(HARDWARE_INTERNAL_MODULE)
+#if defined(INTERNAL_MODULE_MULTI)
   if (moduleIdx == INTERNAL_MODULE) {
     intmodulePulsesData.multi.sendByte(b);
   }
@@ -222,7 +222,6 @@ static void* multiInit(uint8_t module)
   
   // serial port setup
   intmodulePulsesData.multi.initFrame();
-  intmoduleFifo.clear();
   void* uart_ctx = IntmoduleSerialDriver.init(&multiSerialInitParams);
 
   // mixer setup
@@ -266,6 +265,11 @@ static void multiSendPulses(void* context)
                                    intmodulePulsesData.multi.getSize());
 }
 
+static int multiGetByte(void* context, uint8_t* data)
+{
+  return IntmoduleSerialDriver.getByte(context, data);
+}
+
 #include "hal/module_driver.h"
 
 const etx_module_driver_t MultiInternalDriver = {
@@ -273,7 +277,8 @@ const etx_module_driver_t MultiInternalDriver = {
   .init = multiInit,
   .deinit = multiDeInit,
   .setupPulses = multiSetupPulses,
-  .sendPulses = multiSendPulses  
+  .sendPulses = multiSendPulses,
+  .getByte = multiGetByte,
 };
 #endif
 
diff --git a/radio/src/pulses/pulses.cpp b/radio/src/pulses/pulses.cpp
index 60980dbde..c24f64ae5 100755
--- a/radio/src/pulses/pulses.cpp
+++ b/radio/src/pulses/pulses.cpp
@@ -356,6 +356,16 @@ uint8_t getRequiredProtocol(uint8_t module)
 static void* internalModuleContext = nullptr;
 static const etx_module_driver_t* internalModuleDriver = nullptr;
 
+const etx_module_driver_t* getIntModuleDriver()
+{
+  return internalModuleDriver;
+}
+
+void* getIntModuleCtx()
+{
+  return internalModuleContext;
+}
+
 static void enablePulsesInternalModule(uint8_t protocol)
 {
   // start new protocol hardware here
@@ -519,6 +529,16 @@ bool setupPulsesInternalModule()
 static void* externalModuleContext = nullptr;
 static const etx_module_driver_t* externalModuleDriver = nullptr;
 
+const etx_module_driver_t* getExtModuleDriver()
+{
+  return externalModuleDriver;
+}
+
+void* getExtModuleCtx()
+{
+  return externalModuleContext;
+}
+
 void enablePulsesExternalModule(uint8_t protocol)
 {
   // start new protocol hardware here
diff --git a/radio/src/pulses/pulses.h b/radio/src/pulses/pulses.h
index 48126248c..d08f4d393 100644
--- a/radio/src/pulses/pulses.h
+++ b/radio/src/pulses/pulses.h
@@ -229,11 +229,15 @@ extern TrainerPulsesData trainerPulsesData;
 bool setupPulsesInternalModule();
 void stopPulsesInternalModule();
 void intmoduleSendNextFrame();
+const etx_module_driver_t* getIntModuleDriver();
+void* getIntModuleCtx();
 #endif
 #if defined(HARDWARE_EXTERNAL_MODULE)
 bool setupPulsesExternalModule();
 void stopPulsesExternalModule();
 void extmoduleSendNextFrame();
+const etx_module_driver_t* getExtModuleDriver();
+void* getExtModuleCtx();
 #endif
 void restartModule(uint8_t idx);
 void setupPulsesDSM2();
@@ -251,7 +255,6 @@ void intmodulePpmStart();
 void intmodulePxx1PulsesStart();
 void intmodulePxx1SerialStart();
 void extmodulePxx1PulsesStart();
-void extmodulePxx1SerialStart();
 void extmodulePpmStart();
 void intmoduleStop();
 void extmoduleStop();
diff --git a/radio/src/pulses/pxx2.cpp b/radio/src/pulses/pxx2.cpp
index 05cee83d3..07909c753 100644
--- a/radio/src/pulses/pxx2.cpp
+++ b/radio/src/pulses/pxx2.cpp
@@ -648,7 +648,6 @@ void Pxx2OtaUpdate::flashFirmware(const char * filename, ProgressHandler progres
 
 static void* pxx2InitInternal(uint8_t moduleType)
 {
-  intmoduleFifo.clear();
   void* uart_ctx = IntmoduleSerialDriver.init(&pxx2SerialInitParams);
   resetAccessAuthenticationCount();
 
@@ -697,6 +696,11 @@ static void pxx2SendPulsesInternal(void* context)
   }
 }
 
+static int pxx2GetByteInternal(void* context, uint8_t* data)
+{
+  return IntmoduleSerialDriver.getByte(context, data);
+}
+
 #include "hal/module_driver.h"
 
 const etx_module_driver_t Pxx2InternalDriver = {
@@ -705,6 +709,7 @@ const etx_module_driver_t Pxx2InternalDriver = {
   .deinit = pxx2DeInitInternal,
   .setupPulses = pxx2SetupPulsesInternal,
   .sendPulses = pxx2SendPulsesInternal,
+  .getByte = pxx2GetByteInternal,
 };
 
 #if defined(EXTMODULE_USART)
diff --git a/radio/src/pulses/pxx2.h b/radio/src/pulses/pxx2.h
index be832e510..1929d6f13 100644
--- a/radio/src/pulses/pxx2.h
+++ b/radio/src/pulses/pxx2.h
@@ -23,9 +23,8 @@
 #define _PULSES_PXX2_H_
 
 #include "fifo.h"
-#include "io/frsky_pxx2.h"
 #include "popups.h"
-#include "./pxx.h"
+#include "pxx.h"
 
 #include "hal/serial_driver.h"
 #include "hal/module_driver.h"
@@ -424,9 +423,6 @@ PXX2ModuleSetup& getPXX2ModuleSetupBuffer();
 BindInformation& getPXX2BindInformationBuffer();
 PXX2HardwareAndSettings& getPXX2HardwareAndSettingsBuffer();
 
-extern ModuleFifo intmoduleFifo;
-extern ModuleFifo extmoduleFifo;
-
 class Pxx2CrcMixin {
   protected:
     void initCrc()
diff --git a/radio/src/targets/common/arm/stm32/extmodule_serial_driver.cpp b/radio/src/targets/common/arm/stm32/extmodule_serial_driver.cpp
index dfc2947f1..3715433b8 100644
--- a/radio/src/targets/common/arm/stm32/extmodule_serial_driver.cpp
+++ b/radio/src/targets/common/arm/stm32/extmodule_serial_driver.cpp
@@ -25,9 +25,16 @@
 
 #if defined(EXTMODULE_USART)
 #include "stm32_usart_driver.h"
+#include "fifo.h"
 
-#include "io/frsky_pxx2.h"
-ModuleFifo extmoduleFifo;
+typedef Fifo<uint8_t, INTMODULE_FIFO_SIZE> RxFifo;
+static RxFifo extmoduleFifo;
+
+struct ExtmoduleCtx
+{
+  RxFifo* rxFifo;
+  const stm32_usart_t* usart;
+};
 
 static etx_serial_callbacks_t extmodule_driver = {
   nullptr, nullptr, nullptr
@@ -69,6 +76,11 @@ static const stm32_usart_t extmoduleUSART = {
   .rxDMA_Channel = 0,
 };
 
+static const ExtmoduleCtx extmoduleCtx = {
+  .rxFifo = &extmoduleFifo,
+  .usart = &extmoduleUSART,
+};
+
 static void* extmoduleSerialStart(const etx_serial_init* params)
 {
   if (!params) return nullptr;
@@ -78,9 +90,9 @@ static void* extmoduleSerialStart(const etx_serial_init* params)
 
   // UART config
   stm32_usart_init(&extmoduleUSART, params);
-  extmoduleFifo.clear();
+  extmoduleCtx.rxFifo->clear();
 
-  return nullptr;
+  return (void*)&extmoduleCtx;
 }
 
 void extmoduleInvertedSerialStart(uint32_t baudrate)
@@ -91,16 +103,6 @@ void extmoduleInvertedSerialStart(uint32_t baudrate)
   extmoduleSerialStart(&params);
 }
 
-#if defined(PXX1)
-void extmodulePxx1SerialStart()
-{
-  EXTERNAL_MODULE_ON();
-  etx_serial_init params(extmoduleSerialParams);
-  params.baudrate = EXTMODULE_PXX1_SERIAL_BAUDRATE;
-  ExtmoduleSerialDriver.init(&params);
-}
-#endif
-
 void extmoduleSerialStop(void*)
 {
   stm32_usart_deinit(&extmoduleUSART);
@@ -110,20 +112,37 @@ void extmoduleSerialStop(void*)
   extmodule_driver.on_error = nullptr;
 }
 
-static void extmoduleSendByte(void*, uint8_t byte)
+static void extmoduleSendByte(void* ctx, uint8_t byte)
 {
-  stm32_usart_send_byte(&extmoduleUSART, byte);
+  auto modCtx = (ExtmoduleCtx*)ctx;
+  stm32_usart_send_byte(modCtx->usart, byte);
 }
 
-static void extmoduleSendBuffer(void*, const uint8_t * data, uint8_t size)
+static void extmoduleSendBuffer(void* ctx, const uint8_t * data, uint8_t size)
 {
+  auto modCtx = (ExtmoduleCtx*)ctx;
   if (size == 0) return;
-  stm32_usart_send_buffer(&extmoduleUSART, data, size);
+  stm32_usart_send_buffer(modCtx->usart, data, size);
 }
 
-static void extmoduleWaitForTxCompleted(void*)
+static void extmoduleWaitForTxCompleted(void* ctx)
 {
-  stm32_usart_wait_for_tx_dma(&extmoduleUSART);
+  auto modCtx = (ExtmoduleCtx*)ctx;
+  stm32_usart_wait_for_tx_dma(modCtx->usart);
+}
+
+static int extmoduleGetByte(void* ctx, uint8_t* data)
+{
+  auto modCtx = (ExtmoduleCtx*)ctx;
+  if (!modCtx->rxFifo) return -1;
+  return modCtx->rxFifo->pop(*data);
+}
+
+static void extmoduleClearRxBuffer(void* ctx)
+{
+  auto modCtx = (ExtmoduleCtx*)ctx;
+  if (!modCtx->rxFifo) return;
+  modCtx->rxFifo->clear();
 }
 
 const etx_serial_driver_t ExtmoduleSerialDriver = {
@@ -132,7 +151,8 @@ const etx_serial_driver_t ExtmoduleSerialDriver = {
   .sendByte = extmoduleSendByte,
   .sendBuffer = extmoduleSendBuffer,
   .waitForTxCompleted = extmoduleWaitForTxCompleted,
-  .getByte = nullptr,
+  .getByte = extmoduleGetByte,
+  .clearRxBuffer = extmoduleClearRxBuffer,
   .getBaudrate = nullptr,
   .setReceiveCb = nullptr,
   .setBaudrateCb = nullptr,
diff --git a/radio/src/targets/common/arm/stm32/extmodule_serial_driver.h b/radio/src/targets/common/arm/stm32/extmodule_serial_driver.h
index c12246b1f..d38136e86 100644
--- a/radio/src/targets/common/arm/stm32/extmodule_serial_driver.h
+++ b/radio/src/targets/common/arm/stm32/extmodule_serial_driver.h
@@ -30,13 +30,4 @@
 void extmoduleFifoReceive(uint8_t data);
 void extmoduleFifoError();
 
-// void extmoduleSerialStart();
-// void extmoduleInvertedSerialStart(uint32_t baudrate);
-// void extmoduleSendBuffer(const uint8_t * data, uint8_t size);
-// void extmoduleSendNextFrame();
-
-#if defined(PXX1)
-void extmodulePxx1SerialStart();
-#endif
-
 extern const etx_serial_driver_t ExtmoduleSerialDriver;
diff --git a/radio/src/targets/common/arm/stm32/intmodule_serial_driver.cpp b/radio/src/targets/common/arm/stm32/intmodule_serial_driver.cpp
index 1152e0aad..8192326ac 100755
--- a/radio/src/targets/common/arm/stm32/intmodule_serial_driver.cpp
+++ b/radio/src/targets/common/arm/stm32/intmodule_serial_driver.cpp
@@ -23,9 +23,16 @@
 #include "intmodule_serial_driver.h"
 #include "stm32_usart_driver.h"
 #include "board.h"
-#include "fifo.h"
 
-Fifo<uint8_t, INTMODULE_FIFO_SIZE> intmoduleFifo;
+#include "fifo.h"
+typedef Fifo<uint8_t, INTMODULE_FIFO_SIZE> RxFifo;
+static RxFifo intmoduleFifo;
+
+struct IntmoduleCtx
+{
+  RxFifo* rxFifo;
+  const stm32_usart_t* usart;
+};
 
 #if !defined(INTMODULE_DMA_STREAM)
 static uint8_t * intmoduleTxBufferData;
@@ -88,6 +95,11 @@ static const stm32_usart_t intmoduleUSART = {
   .rxDMA_Channel = 0,
 };
 
+static const IntmoduleCtx intmoduleCtx = {
+  .rxFifo = &intmoduleFifo,
+  .usart = &intmoduleUSART,
+};
+
 void intmoduleStop()
 {
   stm32_usart_deinit(&intmoduleUSART);
@@ -115,7 +127,9 @@ void* intmoduleSerialStart(const etx_serial_init* params)
   intmodule_driver.on_error = nullptr;
 
   stm32_usart_init(&intmoduleUSART, params);
-  return nullptr;
+
+  intmoduleCtx.rxFifo->clear();
+  return (void*)&intmoduleCtx;
 }
 
 #define USART_FLAG_ERRORS (USART_FLAG_ORE | USART_FLAG_NE | USART_FLAG_FE | USART_FLAG_PE)
@@ -126,13 +140,13 @@ extern "C" void INTMODULE_USART_IRQHandler(void)
 
 void intmoduleSendByte(void* ctx, uint8_t byte)
 {
-  (void)ctx;
-  stm32_usart_send_byte(&intmoduleUSART, byte);
+  auto modCtx = (IntmoduleCtx*)ctx;
+  stm32_usart_send_byte(modCtx->usart, byte);
 }
 
 void intmoduleSendBuffer(void* ctx, const uint8_t * data, uint8_t size)
 {
-  (void)ctx;
+  auto modCtx = (IntmoduleCtx*)ctx;
   if (size == 0)
     return;
 
@@ -140,26 +154,41 @@ void intmoduleSendBuffer(void* ctx, const uint8_t * data, uint8_t size)
   intmoduleTxBufferData = (uint8_t *)data;
   intmoduleTxBufferRemaining = size;
 #endif
-  stm32_usart_send_buffer(&intmoduleUSART, data, size);
+  stm32_usart_send_buffer(modCtx->usart, data, size);
 }
 
 void intmoduleWaitForTxCompleted(void* ctx)
 {
-  (void)ctx;
+  auto modCtx = (IntmoduleCtx*)ctx;
 #if defined(INTMODULE_DMA_STREAM)
-  stm32_usart_wait_for_tx_dma(&intmoduleUSART);
+  stm32_usart_wait_for_tx_dma(modCtx->usart);
 #else
   while (intmoduleTxBufferRemaining > 0);
 #endif
 }
 
+static int intmoduleGetByte(void* ctx, uint8_t* data)
+{
+  auto modCtx = (IntmoduleCtx*)ctx;
+  if (!modCtx->rxFifo) return -1;
+  return modCtx->rxFifo->pop(*data);
+}
+
+static void intmoduleClearRxBuffer(void* ctx)
+{
+  auto modCtx = (IntmoduleCtx*)ctx;
+  if (!modCtx->rxFifo) return;
+  modCtx->rxFifo->clear();
+}
+
 const etx_serial_driver_t IntmoduleSerialDriver = {
   .init = intmoduleSerialStart,
   .deinit = intmoduleStop,
   .sendByte = intmoduleSendByte,
   .sendBuffer = intmoduleSendBuffer,
   .waitForTxCompleted = intmoduleWaitForTxCompleted,
-  .getByte = nullptr,
+  .getByte = intmoduleGetByte,
+  .clearRxBuffer = intmoduleClearRxBuffer,
   .getBaudrate = nullptr,
   .setReceiveCb = nullptr,
   .setBaudrateCb = nullptr,
diff --git a/radio/src/targets/common/arm/stm32/usbd_cdc.cpp b/radio/src/targets/common/arm/stm32/usbd_cdc.cpp
index 3ae688059..c54bb29e3 100644
--- a/radio/src/targets/common/arm/stm32/usbd_cdc.cpp
+++ b/radio/src/targets/common/arm/stm32/usbd_cdc.cpp
@@ -297,15 +297,16 @@ void usbSerialSetBaudRateCb(void*, void (*cb)(uint32_t))
 // }
 
 static const etx_serial_driver_t usbSerialDriver = {
-  nullptr,
-  nullptr,
-  usbSerialPutc,
-  nullptr,
-  nullptr,
-  nullptr,
-  usbSerialBaudRate,
-  usbSerialSetReceiveDataCb,
-  usbSerialSetBaudRateCb,
+  .init = nullptr,
+  .deinit = nullptr,
+  .sendByte = usbSerialPutc,
+  .sendBuffer = nullptr,
+  .waitForTxCompleted = nullptr,
+  .getByte = nullptr,
+  .clearRxBuffer = nullptr,
+  .getBaudrate = usbSerialBaudRate,
+  .setReceiveCb = usbSerialSetReceiveDataCb,
+  .setBaudrateCb = usbSerialSetBaudRateCb,
 };
 
 const etx_serial_port_t UsbSerialPort = {
diff --git a/radio/src/targets/simu/module_drivers.cpp b/radio/src/targets/simu/module_drivers.cpp
index f11a2f19c..9ebd13eca 100644
--- a/radio/src/targets/simu/module_drivers.cpp
+++ b/radio/src/targets/simu/module_drivers.cpp
@@ -19,14 +19,11 @@
  * GNU General Public License for more details.
  */
 
+#include "hal.h"
 #include "hal/serial_driver.h"
 #include "intmodule_serial_driver.h"
 #include "extmodule_serial_driver.h"
 
-#include "io/frsky_pxx2.h"
-ModuleFifo intmoduleFifo;
-ModuleFifo extmoduleFifo;
-
 void intmoduleStop() {}
 void intmoduleFifoError() {}
 void intmoduleFifoReceive(uint8_t){}
@@ -40,7 +37,6 @@ void extmoduleFifoReceive(uint8_t){}
 
 void extmodulePpmStart(unsigned short, bool) {}
 void extmoduleSerialStart() {}
-void extmodulePxx1SerialStart() {}
 void extmodulePxx1PulsesStart() {}
 void extmoduleInitTxPin() {}
 void extmoduleSendInvertedByte(uint8_t) {}
@@ -78,6 +74,7 @@ const etx_serial_driver_t IntmoduleSerialDriver = {
     .sendBuffer = sendBuffer,
     .waitForTxCompleted = waitForTxCompleted,
     .getByte = getByte,
+    .clearRxBuffer = nullptr,
     .getBaudrate = nullptr,
     .setReceiveCb = nullptr,
     .setBaudrateCb = nullptr,
@@ -90,6 +87,7 @@ const etx_serial_driver_t ExtmoduleSerialDriver = {
     .sendBuffer = sendBuffer,
     .waitForTxCompleted = waitForTxCompleted,
     .getByte = getByte,
+    .clearRxBuffer = nullptr,
     .getBaudrate = nullptr,
     .setReceiveCb = nullptr,
     .setBaudrateCb = nullptr,
diff --git a/radio/src/telemetry/frsky_pxx2.cpp b/radio/src/telemetry/frsky_pxx2.cpp
index 9c0fb04a7..7663b7507 100644
--- a/radio/src/telemetry/frsky_pxx2.cpp
+++ b/radio/src/telemetry/frsky_pxx2.cpp
@@ -31,7 +31,7 @@
 
 static_assert(PXX2_FRAME_MAXLENGTH <= INTMODULE_FIFO_SIZE);
 
-void processGetHardwareInfoFrame(uint8_t module, const uint8_t * frame)
+static void processGetHardwareInfoFrame(uint8_t module, const uint8_t * frame)
 {
   if (moduleState[module].mode != MODULE_MODE_GET_HARDWARE_INFO) {
     return;
@@ -60,7 +60,7 @@ void processGetHardwareInfoFrame(uint8_t module, const uint8_t * frame)
   }
 }
 
-void processModuleSettingsFrame(uint8_t module, const uint8_t * frame)
+static void processModuleSettingsFrame(uint8_t module, const uint8_t * frame)
 {
   if (moduleState[module].mode != MODULE_MODE_MODULE_SETTINGS) {
     return;
@@ -80,7 +80,7 @@ void processModuleSettingsFrame(uint8_t module, const uint8_t * frame)
   moduleState[module].mode = MODULE_MODE_NORMAL;
 }
 
-void processReceiverSettingsFrame(uint8_t module, const uint8_t * frame)
+static void processReceiverSettingsFrame(uint8_t module, const uint8_t * frame)
 {
   if (moduleState[module].mode != MODULE_MODE_RECEIVER_SETTINGS) {
     return;
@@ -117,7 +117,7 @@ void processReceiverSettingsFrame(uint8_t module, const uint8_t * frame)
   moduleState[module].mode = MODULE_MODE_NORMAL;
 }
 
-void processRegisterFrame(uint8_t module, const uint8_t * frame)
+static void processRegisterFrame(uint8_t module, const uint8_t * frame)
 {
   if (moduleState[module].mode != MODULE_MODE_REGISTER) {
     return;
@@ -153,7 +153,7 @@ void processRegisterFrame(uint8_t module, const uint8_t * frame)
   }
 }
 
-void processBindFrame(uint8_t module, const uint8_t * frame)
+static void processBindFrame(uint8_t module, const uint8_t * frame)
 {
   if (moduleState[module].mode != MODULE_MODE_BIND) {
     return;
@@ -204,7 +204,7 @@ void processBindFrame(uint8_t module, const uint8_t * frame)
   }
 }
 
-void processResetFrame(uint8_t module, const uint8_t * frame)
+static void processResetFrame(uint8_t module, const uint8_t * frame)
 {
   if (moduleState[module].mode != MODULE_MODE_RESET) {
     return;
@@ -217,7 +217,7 @@ void processResetFrame(uint8_t module, const uint8_t * frame)
   moduleState[module].mode = MODULE_MODE_NORMAL;
 }
 
-void processTelemetryFrame(uint8_t module, const uint8_t * frame)
+static void processTelemetryFrame(uint8_t module, const uint8_t * frame)
 {
   for (uint8_t i = 0; i < 1 + frame[0]; i++) {
     telemetryMirrorSend(frame[i]);
@@ -237,7 +237,7 @@ extern "C" {
 
 volatile int16_t authenticateFrames = 0;
 
-void processAuthenticationFrame(uint8_t module, const uint8_t * frame)
+static void processAuthenticationFrame(uint8_t module, const uint8_t * frame)
 {
   uint8_t cryptoType = frame[3];
   uint8_t messageDigest[16] = {0};
@@ -280,7 +280,7 @@ void processAuthenticationFrame(uint8_t module, const uint8_t * frame)
 #define processAuthenticationFrame(module, frame)
 #endif
 
-void processSpectrumAnalyserFrame(uint8_t module, const uint8_t * frame)
+static void processSpectrumAnalyserFrame(uint8_t module, const uint8_t * frame)
 {
   if (moduleState[module].mode != MODULE_MODE_SPECTRUM_ANALYSER) {
     return;
@@ -307,7 +307,7 @@ void processSpectrumAnalyserFrame(uint8_t module, const uint8_t * frame)
   }
 }
 
-void processPowerMeterFrame(uint8_t module, const uint8_t * frame)
+static void processPowerMeterFrame(uint8_t module, const uint8_t * frame)
 {
   if (moduleState[module].mode != MODULE_MODE_POWER_METER) {
     return;
@@ -319,7 +319,7 @@ void processPowerMeterFrame(uint8_t module, const uint8_t * frame)
   }
 }
 
-void processOtaUpdateFrame(uint8_t module, const uint8_t * frame)
+static void processOtaUpdateFrame(uint8_t module, const uint8_t * frame)
 {
   if (moduleState[module].mode != MODULE_MODE_OTA_UPDATE) {
     return;
@@ -345,7 +345,7 @@ void processOtaUpdateFrame(uint8_t module, const uint8_t * frame)
   }
 }
 
-void processModuleFrame(uint8_t module, const uint8_t *frame)
+static void processModuleFrame(uint8_t module, const uint8_t *frame)
 {
   switch (frame[2]) {
     case PXX2_TYPE_ID_HW_INFO:
@@ -382,7 +382,7 @@ void processModuleFrame(uint8_t module, const uint8_t *frame)
   }
 }
 
-void processToolsFrame(uint8_t module, const uint8_t * frame)
+static void processToolsFrame(uint8_t module, const uint8_t * frame)
 {
   switch (frame[2]) {
     case PXX2_TYPE_ID_POWER_METER:
@@ -395,7 +395,7 @@ void processToolsFrame(uint8_t module, const uint8_t * frame)
   }
 }
 
-void processPXX2Frame(uint8_t module, const uint8_t * frame)
+static void processPXX2Frame(uint8_t module, const uint8_t * frame)
 {
   LOG_TELEMETRY_WRITE_START();
   for (uint8_t i = 0; i < 1 + frame[0]; i++) {
@@ -419,3 +419,50 @@ void processPXX2Frame(uint8_t module, const uint8_t * frame)
       break;
   }
 }
+
+void processPXX2TelemetryData(uint8_t data, uint8_t idx)
+{
+  uint8_t * rxBuffer = getTelemetryRxBuffer(idx);
+  uint8_t &rxBufferCount = getTelemetryRxBufferCount(idx);
+
+  if (rxBufferCount == 0 && data != START_STOP) {
+    return;
+  }
+
+  if (rxBufferCount == 1 && data > 40) {
+    rxBufferCount = 0;
+    return;
+  }
+
+  if (rxBufferCount < TELEMETRY_RX_PACKET_SIZE) {
+    rxBuffer[rxBufferCount++] = data;
+  }
+  else {
+    TRACE("[PXX2] array size %d error", rxBufferCount);
+    rxBufferCount = 0;
+  }
+
+  uint8_t len = rxBuffer[1];
+  /* 1 byte start + 2 bytes header + 2 bytes CRC = 5 */
+  if (rxBufferCount < unsigned(len + 5)) {
+    return;
+  }
+
+  uint16_t crc = 0xFFFF;
+  uint8_t* frame = rxBuffer + 1;
+
+  for (uint32_t i = 1; i <= len; i++) {
+    crc -= frame[i];
+  }
+
+  uint8_t crcHigh = frame[len + 1];
+  uint8_t crcLow = frame[len + 2];
+  
+  if (((crc >> 8) != crcHigh) || ((crc & 0xFF) == crcLow)) {
+    TRACE("[PXX2] crc error");
+    rxBufferCount = 0;
+    return;
+  }
+
+  processPXX2Frame(idx, frame);
+}
diff --git a/radio/src/telemetry/telemetry.cpp b/radio/src/telemetry/telemetry.cpp
index a749c5e89..0a2c58bec 100644
--- a/radio/src/telemetry/telemetry.cpp
+++ b/radio/src/telemetry/telemetry.cpp
@@ -57,6 +57,10 @@
   #include "flysky_ibus.h"
 #endif
 
+#if defined(INTMODULE_USART)
+#include "intmodule_serial_driver.h"
+#endif
+
 uint8_t telemetryStreaming = 0;
 uint8_t telemetryRxBuffer[TELEMETRY_RX_PACKET_SIZE];   // Receive buffer. 9 bytes (full packet), worst case 18 bytes with byte-stuffing (+1)
 uint8_t telemetryRxBufferCount = 0;
@@ -236,28 +240,6 @@ inline bool isBadAntennaDetected()
   return false;
 }
 
-#if defined(INTERNAL_MODULE_PXX2)
-static void pollIntPXX2()
-{
-  uint8_t frame[PXX2_FRAME_MAXLENGTH];
-
-  while (intmoduleFifo.getFrame(frame)) {
-    processPXX2Frame(INTERNAL_MODULE, frame);
-  }
-}
-#endif  
-
-#if defined(PXX2) && defined(EXTMODULE_USART)
-static void pollExtPXX2()
-{
-  uint8_t frame[PXX2_FRAME_MAXLENGTH];
-
-  while (extmoduleFifo.getFrame(frame)) {
-    processPXX2Frame(EXTERNAL_MODULE, frame);
-  }
-}
-#endif  
-
 #if defined(MULTI_PROTOLIST)
 static inline void pollMultiProtolist(uint8_t idx)
 {
@@ -268,19 +250,51 @@ static inline void pollMultiProtolist(uint8_t idx)
 }
 #endif
 
-static inline void pollIntTelemetry(void (*processData)(uint8_t,uint8_t))
+static inline void pollIntTelemetry(void (*processData)(uint8_t, uint8_t))
 {
+  auto drv = getIntModuleDriver();
+  auto ctx = getIntModuleCtx();
+
+  if (!drv || !drv->getByte || !processData) return;
+  
   uint8_t data;
-  if (intmoduleFifo.pop(data)) {
+  if (drv->getByte(ctx, &data) > 0) {
     LOG_TELEMETRY_WRITE_START();
     do {
       telemetryMirrorSend(data);
       processData(data, INTERNAL_MODULE);
       LOG_TELEMETRY_WRITE_BYTE(data);
-    } while (intmoduleFifo.pop(data));
-  }  
+    } while (drv->getByte(ctx, &data) > 0);
+  }
 }
 
+#if defined(INTERNAL_MODULE_PXX2)
+static void pollIntPXX2()
+{
+  pollIntTelemetry(processPXX2TelemetryData);
+}
+#endif  
+
+#if defined(PXX2) && defined(EXTMODULE_USART)
+static void pollExtPXX2()
+{
+  auto drv = getExtModuleDriver();
+  auto ctx = getExtModuleCtx();
+
+  if (!drv || !drv->getByte) return;
+  
+  uint8_t data;
+  if (drv->getByte(ctx, &data) > 0) {
+    LOG_TELEMETRY_WRITE_START();
+    do {
+      telemetryMirrorSend(data);
+      processPXX2TelemetryData(data, EXTERNAL_MODULE);
+      LOG_TELEMETRY_WRITE_BYTE(data);
+    } while (drv->getByte(ctx, &data) > 0);
+  }
+}
+#endif  
+
 #if defined(INTERNAL_MODULE_MULTI)
 static void pollIntMulti()
 {
diff --git a/radio/src/telemetry/telemetry.h b/radio/src/telemetry/telemetry.h
index 4b0403218..8731a91bb 100644
--- a/radio/src/telemetry/telemetry.h
+++ b/radio/src/telemetry/telemetry.h
@@ -50,7 +50,7 @@ constexpr uint8_t TELEMETRY_TIMEOUT10ms = 100; // 1 second
 #define TELEMETRY_SERIAL_8E2           1
 #define TELEMETRY_SERIAL_WITHOUT_DMA   2
 
-#if defined(CROSSFIRE) || defined(MULTIMODULE) || defined(AFHDS3)
+#if defined(CROSSFIRE) || defined(MULTIMODULE) || defined(AFHDS3) || defined(PXX2)
 #define TELEMETRY_RX_PACKET_SIZE       128
 // multi module Spektrum telemetry is 18 bytes, FlySky is 37 bytes
 #else
@@ -304,7 +304,7 @@ extern OutputTelemetryBuffer outputTelemetryBuffer __DMA;
 extern Fifo<uint8_t, LUA_TELEMETRY_INPUT_FIFO_SIZE> * luaInputTelemetryFifo;
 #endif
 
-void processPXX2Frame(uint8_t module, const uint8_t *frame);
+void processPXX2TelemetryData(uint8_t data, uint8_t idx);
 
 // Module pulse synchronization
 struct ModuleSyncStatus