diff --git a/flight/Bootloaders/CopterControl/Makefile b/flight/Bootloaders/CopterControl/Makefile
index 1257ed579..a5effde9c 100644
--- a/flight/Bootloaders/CopterControl/Makefile
+++ b/flight/Bootloaders/CopterControl/Makefile
@@ -116,7 +116,7 @@ SRC += $(PIOSCOMMON)/pios_usb_desc_hid_only.c
 
 ## PIOS Hardware (Common)
 SRC += $(PIOSCOMMON)/pios_board_info.c
-SRC += $(PIOSCOMMON)/pios_com.c
+SRC += $(PIOSCOMMON)/pios_com_msg.c
 SRC += $(PIOSCOMMON)/pios_bl_helper.c
 SRC += $(PIOSCOMMON)/pios_iap.c
 SRC += $(PIOSCOMMON)/printf-stdarg.c
diff --git a/flight/Bootloaders/CopterControl/inc/pios_config.h b/flight/Bootloaders/CopterControl/inc/pios_config.h
index 081ed1b0f..864ed4665 100644
--- a/flight/Bootloaders/CopterControl/inc/pios_config.h
+++ b/flight/Bootloaders/CopterControl/inc/pios_config.h
@@ -39,7 +39,7 @@
 #define PIOS_INCLUDE_SYS
 #define PIOS_INCLUDE_USB
 #define PIOS_INCLUDE_USB_HID
-#define PIOS_INCLUDE_COM
+#define PIOS_INCLUDE_COM_MSG
 #define PIOS_INCLUDE_GPIO
 #define PIOS_NO_GPS
 
diff --git a/flight/Bootloaders/CopterControl/main.c b/flight/Bootloaders/CopterControl/main.c
index c1def4a46..7a61ae9e9 100644
--- a/flight/Bootloaders/CopterControl/main.c
+++ b/flight/Bootloaders/CopterControl/main.c
@@ -32,6 +32,7 @@
 #include "usb_lib.h"
 #include "pios_iap.h"
 #include "fifo_buffer.h"
+#include "pios_com_msg.h"
 /* Prototype of PIOS_Board_Init() function */
 extern void PIOS_Board_Init(void);
 extern void FLASH_Download();
@@ -62,7 +63,7 @@ uint8_t JumpToApp = FALSE;
 uint8_t GO_dfu = FALSE;
 uint8_t USB_connected = FALSE;
 uint8_t User_DFU_request = FALSE;
-static uint8_t mReceive_Buffer[64];
+static uint8_t mReceive_Buffer[63];
 /* Private function prototypes -----------------------------------------------*/
 uint32_t LedPWM(uint32_t pwm_period, uint32_t pwm_sweep_steps, uint32_t count);
 uint8_t processRX();
@@ -198,7 +199,7 @@ uint32_t LedPWM(uint32_t pwm_period, uint32_t pwm_sweep_steps, uint32_t count) {
 }
 
 uint8_t processRX() {
-	if (PIOS_COM_ReceiveBuffer(PIOS_COM_TELEM_USB, mReceive_Buffer, 63, 0) == 63) {
+	if (PIOS_COM_MSG_Receive(PIOS_COM_TELEM_USB, mReceive_Buffer, sizeof(mReceive_Buffer))) {
 		processComand(mReceive_Buffer);
 	}
 	return TRUE;
diff --git a/flight/Bootloaders/CopterControl/op_dfu.c b/flight/Bootloaders/CopterControl/op_dfu.c
index ae85160c2..9f98d3394 100644
--- a/flight/Bootloaders/CopterControl/op_dfu.c
+++ b/flight/Bootloaders/CopterControl/op_dfu.c
@@ -30,6 +30,7 @@
 #include "pios.h"
 #include "op_dfu.h"
 #include "pios_bl_helper.h"
+#include "pios_com_msg.h"
 #include <pios_board_info.h>
 //programmable devices
 Device devicesTable[10];
@@ -446,9 +447,7 @@ uint32_t CalcFirmCRC() {
 
 }
 void sendData(uint8_t * buf, uint16_t size) {
-	PIOS_COM_SendBuffer(PIOS_COM_TELEM_USB, buf, size);
-	if (DeviceState == downloading)
-		PIOS_DELAY_WaitmS(20);//this is an hack, we should check wtf is wrong with hid
+	PIOS_COM_MSG_Send(PIOS_COM_TELEM_USB, buf, size);
 }
 
 bool flash_read(uint8_t * buffer, uint32_t adr, DFUProgType type) {
diff --git a/flight/Bootloaders/CopterControl/pios_board.c b/flight/Bootloaders/CopterControl/pios_board.c
index 1b3c54af3..972a85be0 100644
--- a/flight/Bootloaders/CopterControl/pios_board.c
+++ b/flight/Bootloaders/CopterControl/pios_board.c
@@ -27,17 +27,11 @@
 
 // ***********************************************************************************
 
-#if defined(PIOS_INCLUDE_COM)
+#if defined(PIOS_INCLUDE_COM_MSG)
 
-#include <pios_com_priv.h>
+#include <pios_com_msg_priv.h>
 
-#define PIOS_COM_TELEM_USB_RX_BUF_LEN 192
-#define PIOS_COM_TELEM_USB_TX_BUF_LEN 192
-
-static uint8_t pios_com_telem_usb_rx_buffer[PIOS_COM_TELEM_USB_RX_BUF_LEN];
-static uint8_t pios_com_telem_usb_tx_buffer[PIOS_COM_TELEM_USB_TX_BUF_LEN];
-
-#endif /* PIOS_INCLUDE_COM */
+#endif /* PIOS_INCLUDE_COM_MSG */
 
 // ***********************************************************************************
 
@@ -97,17 +91,15 @@ void PIOS_Board_Init(void) {
 	if (PIOS_USB_Init(&pios_usb_id, &pios_usb_main_cfg)) {
 		PIOS_Assert(0);
 	}
-#if defined(PIOS_INCLUDE_USB_HID) && defined(PIOS_INCLUDE_COM)
+#if defined(PIOS_INCLUDE_USB_HID) && defined(PIOS_INCLUDE_COM_MSG)
 	uint32_t pios_usb_hid_id;
 	if (PIOS_USB_HID_Init(&pios_usb_hid_id, &pios_usb_hid_cfg, pios_usb_id)) {
 		PIOS_Assert(0);
 	}
-	if (PIOS_COM_Init(&pios_com_telem_usb_id, &pios_usb_hid_com_driver, pios_usb_hid_id,
-			  pios_com_telem_usb_rx_buffer, sizeof(pios_com_telem_usb_rx_buffer),
-			  pios_com_telem_usb_tx_buffer, sizeof(pios_com_telem_usb_tx_buffer))) {
+	if (PIOS_COM_MSG_Init(&pios_com_telem_usb_id, &pios_usb_hid_com_driver, pios_usb_hid_id)) {
 		PIOS_Assert(0);
 	}
-#endif	/* PIOS_INCLUDE_USB_HID && PIOS_INCLUDE_COM */
+#endif	/* PIOS_INCLUDE_USB_HID && PIOS_INCLUDE_COM_MSG */
 
 #endif	/* PIOS_INCLUDE_USB */
 
diff --git a/flight/Bootloaders/OpenPilot/Makefile b/flight/Bootloaders/OpenPilot/Makefile
index e9b55e134..6c3888797 100644
--- a/flight/Bootloaders/OpenPilot/Makefile
+++ b/flight/Bootloaders/OpenPilot/Makefile
@@ -119,6 +119,7 @@ SRC += $(PIOSCOMMON)/pios_usb_desc_hid_only.c
 
 ## PIOS Hardware (Common)
 SRC += $(PIOSCOMMON)/pios_board_info.c
+SRC += $(PIOSCOMMON)/pios_com_msg.c
 SRC += $(PIOSCOMMON)/pios_com.c
 SRC += $(PIOSCOMMON)/pios_opahrs_v0.c
 SRC += $(PIOSCOMMON)/pios_bl_helper.c
diff --git a/flight/Bootloaders/OpenPilot/inc/pios_config.h b/flight/Bootloaders/OpenPilot/inc/pios_config.h
index 024bcae9a..cf8981339 100644
--- a/flight/Bootloaders/OpenPilot/inc/pios_config.h
+++ b/flight/Bootloaders/OpenPilot/inc/pios_config.h
@@ -42,6 +42,7 @@
 #define PIOS_INCLUDE_USB_HID
 #define PIOS_INCLUDE_OPAHRS
 #define PIOS_INCLUDE_COM
+#define PIOS_INCLUDE_COM_MSG
 #define PIOS_INCLUDE_GPIO
 //#define DEBUG_SSP
 
diff --git a/flight/Bootloaders/OpenPilot/main.c b/flight/Bootloaders/OpenPilot/main.c
index 48056cff6..8a9e554ef 100644
--- a/flight/Bootloaders/OpenPilot/main.c
+++ b/flight/Bootloaders/OpenPilot/main.c
@@ -35,6 +35,7 @@
 #include "pios_iap.h"
 #include "ssp.h"
 #include "fifo_buffer.h"
+#include "pios_com_msg.h"
 /* Prototype of PIOS_Board_Init() function */
 extern void PIOS_Board_Init(void);
 extern void FLASH_Download();
@@ -90,7 +91,7 @@ uint8_t JumpToApp = FALSE;
 uint8_t GO_dfu = FALSE;
 uint8_t USB_connected = FALSE;
 uint8_t User_DFU_request = FALSE;
-static uint8_t mReceive_Buffer[64];
+static uint8_t mReceive_Buffer[63];
 /* Private function prototypes -----------------------------------------------*/
 uint32_t LedPWM(uint32_t pwm_period, uint32_t pwm_sweep_steps, uint32_t count);
 uint8_t processRX();
@@ -249,7 +250,7 @@ uint32_t LedPWM(uint32_t pwm_period, uint32_t pwm_sweep_steps, uint32_t count) {
 
 uint8_t processRX() {
 	if (ProgPort == Usb) {
-		if (PIOS_COM_ReceiveBuffer(PIOS_COM_TELEM_USB, mReceive_Buffer, 63, 0) == 63) {
+		if (PIOS_COM_MSG_Receive(PIOS_COM_TELEM_USB, mReceive_Buffer, sizeof(mReceive_Buffer))) {
 			processComand(mReceive_Buffer);
 		}
 	} else if (ProgPort == Serial) {
diff --git a/flight/Bootloaders/OpenPilot/op_dfu.c b/flight/Bootloaders/OpenPilot/op_dfu.c
index bc62fff6c..ad5836ad7 100644
--- a/flight/Bootloaders/OpenPilot/op_dfu.c
+++ b/flight/Bootloaders/OpenPilot/op_dfu.c
@@ -30,6 +30,7 @@
 #include "pios.h"
 #include "op_dfu.h"
 #include "pios_bl_helper.h"
+#include "pios_com_msg.h"
 #include <pios_board_info.h>
 #include "pios_opahrs.h"
 #include "ssp.h"
@@ -299,7 +300,6 @@ void processComand(uint8_t *xReceive_Buffer) {
 
 					++Next_Packet;
 				} else {
-
 					DeviceState = wrong_packet_received;
 					Aditionals = Count;
 				}
@@ -508,6 +508,7 @@ uint32_t baseOfAdressType(DFUTransfer type) {
 		return currentDevice.startOfUserCode + currentDevice.sizeOfCode;
 		break;
 	default:
+
 		return 0;
 	}
 }
@@ -550,11 +551,7 @@ uint32_t CalcFirmCRC() {
 }
 void sendData(uint8_t * buf, uint16_t size) {
 	if (ProgPort == Usb) {
-
-		PIOS_COM_SendBuffer(PIOS_COM_TELEM_USB, buf, size);
-		if (DeviceState == downloading)
-			PIOS_DELAY_WaitmS(10);
-
+		PIOS_COM_MSG_Send(PIOS_COM_TELEM_USB, buf, size);
 	} else if (ProgPort == Serial) {
 		ssp_SendData(&ssp_port, buf, size);
 	}
diff --git a/flight/Bootloaders/OpenPilot/pios_board.c b/flight/Bootloaders/OpenPilot/pios_board.c
index a2630815a..707600b4d 100644
--- a/flight/Bootloaders/OpenPilot/pios_board.c
+++ b/flight/Bootloaders/OpenPilot/pios_board.c
@@ -184,12 +184,6 @@ const struct pios_usart_cfg pios_usart_telem_cfg = {
 
 #include "pios_com_priv.h"
 
-#define PIOS_COM_TELEM_USB_RX_BUF_LEN 192
-#define PIOS_COM_TELEM_USB_TX_BUF_LEN 192
-
-static uint8_t pios_com_telem_usb_rx_buffer[PIOS_COM_TELEM_USB_RX_BUF_LEN];
-static uint8_t pios_com_telem_usb_tx_buffer[PIOS_COM_TELEM_USB_TX_BUF_LEN];
-
 #define PIOS_COM_TELEM_RF_RX_BUF_LEN 192
 #define PIOS_COM_TELEM_RF_TX_BUF_LEN 192
 
@@ -198,6 +192,16 @@ static uint8_t pios_com_telem_rf_tx_buffer[PIOS_COM_TELEM_RF_TX_BUF_LEN];
 
 #endif	/* PIOS_INCLUDE_COM */
 
+// ***********************************************************************************
+
+#if defined(PIOS_INCLUDE_COM_MSG)
+
+#include <pios_com_msg_priv.h>
+
+#endif /* PIOS_INCLUDE_COM_MSG */
+
+// ***********************************************************************************
+
 #if defined(PIOS_INCLUDE_USB)
 #include "pios_usb_priv.h"
 
@@ -270,17 +274,15 @@ void PIOS_Board_Init(void) {
 	if (PIOS_USB_Init(&pios_usb_id, &pios_usb_main_cfg)) {
 		PIOS_Assert(0);
 	}
-#if defined(PIOS_INCLUDE_USB_HID) && defined(PIOS_INCLUDE_COM)
+#if defined(PIOS_INCLUDE_USB_HID) && defined(PIOS_INCLUDE_COM_MSG)
 	uint32_t pios_usb_hid_id;
 	if (PIOS_USB_HID_Init(&pios_usb_hid_id, &pios_usb_hid_cfg, pios_usb_id)) {
 		PIOS_Assert(0);
 	}
-	if (PIOS_COM_Init(&pios_com_telem_usb_id, &pios_usb_hid_com_driver, pios_usb_hid_id,
-			  pios_com_telem_usb_rx_buffer, sizeof(pios_com_telem_usb_rx_buffer),
-			  pios_com_telem_usb_tx_buffer, sizeof(pios_com_telem_usb_tx_buffer))) {
+	if (PIOS_COM_MSG_Init(&pios_com_telem_usb_id, &pios_usb_hid_com_driver, pios_usb_hid_id)) {
 		PIOS_Assert(0);
 	}
-#endif	/* PIOS_INCLUDE_USB_HID && PIOS_INCLUDE_COM */
+#endif	/* PIOS_INCLUDE_USB_HID && PIOS_INCLUDE_COM_MSG */
 
 #endif	/* PIOS_INCLUDE_USB */
 
diff --git a/flight/Bootloaders/PipXtreme/Makefile b/flight/Bootloaders/PipXtreme/Makefile
index af6469ae0..9bad695f7 100644
--- a/flight/Bootloaders/PipXtreme/Makefile
+++ b/flight/Bootloaders/PipXtreme/Makefile
@@ -115,7 +115,7 @@ SRC += $(PIOSCOMMON)/pios_usb_desc_hid_only.c
 
 ## PIOS Hardware (Common)
 SRC += $(PIOSCOMMON)/pios_board_info.c
-SRC += $(PIOSCOMMON)/pios_com.c
+SRC += $(PIOSCOMMON)/pios_com_msg.c
 SRC += $(PIOSCOMMON)/pios_bl_helper.c
 SRC += $(PIOSCOMMON)/pios_iap.c
 SRC += $(PIOSCOMMON)/printf-stdarg.c
diff --git a/flight/Bootloaders/PipXtreme/inc/pios_config.h b/flight/Bootloaders/PipXtreme/inc/pios_config.h
index 0c2cc7877..8084f9c0a 100644
--- a/flight/Bootloaders/PipXtreme/inc/pios_config.h
+++ b/flight/Bootloaders/PipXtreme/inc/pios_config.h
@@ -38,7 +38,7 @@
 #define PIOS_INCLUDE_SYS
 #define PIOS_INCLUDE_USB
 #define PIOS_INCLUDE_USB_HID
-#define PIOS_INCLUDE_COM
+#define PIOS_INCLUDE_COM_MSG
 #define PIOS_INCLUDE_GPIO
 //#define DEBUG_SSP
 
diff --git a/flight/Bootloaders/PipXtreme/main.c b/flight/Bootloaders/PipXtreme/main.c
index f09881d42..4923f8fc1 100644
--- a/flight/Bootloaders/PipXtreme/main.c
+++ b/flight/Bootloaders/PipXtreme/main.c
@@ -32,6 +32,7 @@
 #include "usb_lib.h"
 #include "pios_iap.h"
 #include "fifo_buffer.h"
+#include "pios_com_msg.h"
 /* Prototype of PIOS_Board_Init() function */
 extern void PIOS_Board_Init(void);
 extern void FLASH_Download();
@@ -62,7 +63,7 @@ uint8_t JumpToApp = FALSE;
 uint8_t GO_dfu = FALSE;
 uint8_t USB_connected = FALSE;
 uint8_t User_DFU_request = FALSE;
-static uint8_t mReceive_Buffer[64];
+static uint8_t mReceive_Buffer[63];
 /* Private function prototypes -----------------------------------------------*/
 uint32_t LedPWM(uint32_t pwm_period, uint32_t pwm_sweep_steps, uint32_t count);
 uint8_t processRX();
@@ -204,7 +205,7 @@ uint32_t LedPWM(uint32_t pwm_period, uint32_t pwm_sweep_steps, uint32_t count) {
 }
 
 uint8_t processRX() {
-	if (PIOS_COM_ReceiveBuffer(PIOS_COM_TELEM_USB, mReceive_Buffer, 63, 0) == 63) {
+	if (PIOS_COM_MSG_Receive(PIOS_COM_TELEM_USB, mReceive_Buffer, sizeof(mReceive_Buffer))) {
 		processComand(mReceive_Buffer);
 	}
 	return TRUE;
diff --git a/flight/Bootloaders/PipXtreme/op_dfu.c b/flight/Bootloaders/PipXtreme/op_dfu.c
index 770ce8237..cdc2d82b8 100644
--- a/flight/Bootloaders/PipXtreme/op_dfu.c
+++ b/flight/Bootloaders/PipXtreme/op_dfu.c
@@ -30,6 +30,7 @@
 #include "pios.h"
 #include "op_dfu.h"
 #include "pios_bl_helper.h"
+#include "pios_com_msg.h"
 #include <pios_board_info.h>
 /* Private typedef -----------------------------------------------------------*/
 /* Private define ------------------------------------------------------------*/
@@ -102,33 +103,9 @@ void DataDownload(DownloadAction action) {
 					currentProgrammingDestination)) {
 				DeviceState = Last_operation_failed;
 			}
-			/*
-			 switch (currentProgrammingDestination) {
-			 case Remote_flash_via_spi:
-			 if (downType == Descript) {
-			 SendBuffer[6 + (x * 4)]
-			 = spi_dev_desc[(uint8_t) partoffset];
-			 SendBuffer[7 + (x * 4)] = spi_dev_desc[(uint8_t) partoffset
-			 + 1];
-			 SendBuffer[8 + (x * 4)] = spi_dev_desc[(uint8_t) partoffset
-			 + 2];
-			 SendBuffer[9 + (x * 4)] = spi_dev_desc[(uint8_t) partoffset
-			 + 3];
-			 }
-			 break;
-			 case Self_flash:
-			 SendBuffer[6 + (x * 4)] = *PIOS_BL_HELPER_FLASH_If_Read(offset);
-			 SendBuffer[7 + (x * 4)] = *PIOS_BL_HELPER_FLASH_If_Read(offset + 1);
-			 SendBuffer[8 + (x * 4)] = *PIOS_BL_HELPER_FLASH_If_Read(offset + 2);
-			 SendBuffer[9 + (x * 4)] = *PIOS_BL_HELPER_FLASH_If_Read(offset + 3);
-			 break;
-			 }
-			 */
 		}
-		//PIOS USB_SIL_Write(EP1_IN, (uint8_t*) SendBuffer, 64);
 		downPacketCurrent = downPacketCurrent + 1;
 		if (downPacketCurrent > downPacketTotal - 1) {
-			// STM_EVAL_LEDOn(LED2);
 			DeviceState = Last_operation_Success;
 			Aditionals = (uint32_t) Download;
 		}
@@ -322,7 +299,6 @@ void processComand(uint8_t *xReceive_Buffer) {
 			Buffer[15] = devicesTable[Data0 - 1].devID;
 		}
 		sendData(Buffer + 1, 63);
-		//PIOS_COM_SendBuffer(PIOS_COM_TELEM_USB, Buffer + 1, 63);//FIX+1
 		break;
 	case JumpFW:
 		FLASH_Lock();
@@ -474,9 +450,7 @@ uint32_t CalcFirmCRC() {
 
 }
 void sendData(uint8_t * buf, uint16_t size) {
-	PIOS_COM_SendBuffer(PIOS_COM_TELEM_USB, buf, size);
-	if (DeviceState == downloading)
-		PIOS_DELAY_WaitmS(10);
+	PIOS_COM_MSG_Send(PIOS_COM_TELEM_USB, buf, size);
 }
 
 bool flash_read(uint8_t * buffer, uint32_t adr, DFUProgType type) {
diff --git a/flight/Bootloaders/PipXtreme/pios_board.c b/flight/Bootloaders/PipXtreme/pios_board.c
index abf079340..3c06d820b 100644
--- a/flight/Bootloaders/PipXtreme/pios_board.c
+++ b/flight/Bootloaders/PipXtreme/pios_board.c
@@ -27,17 +27,11 @@
 
 // ***********************************************************************************
 
-#if defined(PIOS_INCLUDE_COM)
+#if defined(PIOS_INCLUDE_COM_MSG)
 
-#include <pios_com_priv.h>
+#include <pios_com_msg_priv.h>
 
-#define PIOS_COM_TELEM_USB_RX_BUF_LEN 192
-#define PIOS_COM_TELEM_USB_TX_BUF_LEN 192
-
-static uint8_t pios_com_telem_usb_rx_buffer[PIOS_COM_TELEM_USB_RX_BUF_LEN];
-static uint8_t pios_com_telem_usb_tx_buffer[PIOS_COM_TELEM_USB_TX_BUF_LEN];
-
-#endif /* PIOS_INCLUDE_COM */
+#endif /* PIOS_INCLUDE_COM_MSG */
 
 // ***********************************************************************************
 
@@ -98,17 +92,16 @@ void PIOS_Board_Init(void) {
 	if (PIOS_USB_Init(&pios_usb_id, &pios_usb_main_cfg)) {
 		PIOS_Assert(0);
 	}
-#if defined(PIOS_INCLUDE_USB_HID) && defined(PIOS_INCLUDE_COM)
-	uint32_t pios_usb_com_id;
-	if (PIOS_USB_HID_Init(&pios_usb_com_id, &pios_usb_hid_cfg, pios_usb_id)) {
+#if defined(PIOS_INCLUDE_USB_HID) && defined(PIOS_INCLUDE_COM_MSG)
+	uint32_t pios_usb_hid_id;
+	if (PIOS_USB_HID_Init(&pios_usb_hid_id, &pios_usb_hid_cfg, pios_usb_id)) {
 		PIOS_Assert(0);
 	}
-	if (PIOS_COM_Init(&pios_com_telem_usb_id, &pios_usb_hid_com_driver, pios_usb_com_id,
-			  pios_com_telem_usb_rx_buffer, sizeof(pios_com_telem_usb_rx_buffer),
-			  pios_com_telem_usb_tx_buffer, sizeof(pios_com_telem_usb_tx_buffer))) {
+	if (PIOS_COM_MSG_Init(&pios_com_telem_usb_id, &pios_usb_hid_com_driver, pios_usb_hid_id)) {
 		PIOS_Assert(0);
 	}
-#endif	/* PIOS_INCLUDE_USB_HID && PIOS_INCLUDE_COM */
+#endif	/* PIOS_INCLUDE_USB_HID && PIOS_INCLUDE_COM_MSG */
+
 #endif	/* PIOS_INCLUDE_USB */
 
 	RCC_AHBPeriphClockCmd(RCC_AHBPeriph_CRC, ENABLE);//TODO Tirar
diff --git a/flight/PiOS/Common/pios_com_msg.c b/flight/PiOS/Common/pios_com_msg.c
new file mode 100644
index 000000000..c1cebe1d9
--- /dev/null
+++ b/flight/PiOS/Common/pios_com_msg.c
@@ -0,0 +1,185 @@
+/**
+ ******************************************************************************
+ * @addtogroup PIOS PIOS Core hardware abstraction layer
+ * @{
+ * @addtogroup PIOS_COM COM MSG layer functions
+ * @brief Hardware communication layer
+ * @{
+ *
+ * @file       pios_com_msg.c  
+ * @author     The OpenPilot Team, http://www.openpilot.org Copyright (C) 2010.
+ * @brief      COM MSG layer functions
+ * @see        The GNU Public License (GPL) Version 3
+ * 
+ *****************************************************************************/
+/* 
+ * This program is free software; you can redistribute it and/or modify 
+ * it under the terms of the GNU General Public License as published by 
+ * the Free Software Foundation; either version 3 of the License, or 
+ * (at your option) any later version.
+ * 
+ * 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.
+ * 
+ * You should have received a copy of the GNU General Public License along 
+ * with this program; if not, write to the Free Software Foundation, Inc., 
+ * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ */
+
+/* Project Includes */
+#include "pios.h"
+
+#if defined(PIOS_INCLUDE_COM_MSG)
+
+#include "pios_com.h"
+
+#define PIOS_COM_MSG_MAX_LEN 63
+
+struct pios_com_msg_dev {
+	uint32_t lower_id;
+	const struct pios_com_driver * driver;
+
+	uint8_t rx_msg_buffer[PIOS_COM_MSG_MAX_LEN];
+	volatile bool rx_msg_full;
+
+	uint8_t tx_msg_buffer[PIOS_COM_MSG_MAX_LEN];
+	volatile bool tx_msg_full;
+};
+
+static struct pios_com_msg_dev com_msg_dev;
+
+static uint16_t PIOS_COM_MSG_TxOutCallback(uint32_t context, uint8_t * buf, uint16_t buf_len, uint16_t * headroom, bool * need_yield);
+static uint16_t PIOS_COM_MSG_RxInCallback(uint32_t context, uint8_t * buf, uint16_t buf_len, uint16_t * headroom, bool * need_yield);
+
+int32_t PIOS_COM_MSG_Init(uint32_t * com_id, const struct pios_com_driver * driver, uint32_t lower_id)
+{
+	PIOS_Assert(com_id);
+	PIOS_Assert(driver);
+
+	PIOS_Assert(driver->bind_tx_cb);
+	PIOS_Assert(driver->bind_rx_cb);
+
+	struct pios_com_msg_dev * com_dev = &com_msg_dev;
+
+	com_dev->driver   = driver;
+	com_dev->lower_id = lower_id;
+
+	com_dev->rx_msg_full = false;
+	(com_dev->driver->bind_rx_cb)(lower_id, PIOS_COM_MSG_RxInCallback, (uint32_t)com_dev);
+	(com_dev->driver->rx_start)(com_dev->lower_id, sizeof(com_dev->rx_msg_buffer));
+
+	com_dev->tx_msg_full = false;
+	(com_dev->driver->bind_tx_cb)(lower_id, PIOS_COM_MSG_TxOutCallback, (uint32_t)com_dev);
+
+	*com_id = (uint32_t)com_dev;
+	return(0);
+}
+
+static uint16_t PIOS_COM_MSG_TxOutCallback(uint32_t context, uint8_t * buf, uint16_t buf_len, uint16_t * headroom, bool * need_yield)
+{
+	struct pios_com_msg_dev * com_dev = (struct pios_com_msg_dev *)context;
+
+	PIOS_Assert(buf);
+	PIOS_Assert(buf_len);
+
+	uint16_t bytes_from_fifo = 0;
+
+	if (com_dev->tx_msg_full && (buf_len >= sizeof(com_dev->tx_msg_buffer))) {
+		/* Room for an entire message, send it */
+		memcpy(buf, com_dev->tx_msg_buffer, sizeof(com_dev->tx_msg_buffer));
+		bytes_from_fifo = sizeof(com_dev->tx_msg_buffer);
+		com_dev->tx_msg_full = false;
+	}
+
+	if (headroom) {
+		if (com_dev->tx_msg_full) {
+			*headroom = sizeof(com_dev->tx_msg_buffer);
+		} else {
+			*headroom = 0;
+		}
+	}
+
+	return (bytes_from_fifo);
+}
+
+static uint16_t PIOS_COM_MSG_RxInCallback(uint32_t context, uint8_t * buf, uint16_t buf_len, uint16_t * headroom, bool * need_yield)
+{
+	struct pios_com_msg_dev * com_dev = (struct pios_com_msg_dev *)context;
+
+	uint16_t bytes_into_fifo = 0;
+
+	if (!com_dev->rx_msg_full && (buf_len >= sizeof(com_dev->rx_msg_buffer))) {
+		memcpy(com_dev->rx_msg_buffer, buf, sizeof(com_dev->rx_msg_buffer));
+		bytes_into_fifo = sizeof(com_dev->rx_msg_buffer);
+		com_dev->rx_msg_full = true;
+	}
+
+	if (headroom) {
+		if (!com_dev->rx_msg_full) {
+			*headroom = sizeof(com_dev->rx_msg_buffer);
+		} else {
+			*headroom = 0;
+		}
+	}
+
+	return (bytes_into_fifo);
+}
+
+int32_t PIOS_COM_MSG_Send(uint32_t com_id, const uint8_t *msg, uint16_t msg_len)
+{
+	PIOS_Assert(msg);
+	PIOS_Assert(msg_len);
+
+	struct pios_com_msg_dev * com_dev = (struct pios_com_msg_dev *)com_id;
+
+	PIOS_Assert(msg_len == sizeof(com_dev->tx_msg_buffer));
+
+	/* Wait forever for room in the tx buffer */
+	while (com_dev->tx_msg_full) {
+		/* Kick the transmitter while we wait */
+		if (com_dev->driver->tx_start) {
+			(com_dev->driver->tx_start)(com_dev->lower_id, sizeof(com_dev->tx_msg_buffer));
+		}
+	}
+
+	memcpy((void *) com_dev->tx_msg_buffer, msg, msg_len);
+	com_dev->tx_msg_full = true;
+
+	/* Kick the transmitter now that we've queued our message */
+	if (com_dev->driver->tx_start) {
+		(com_dev->driver->tx_start)(com_dev->lower_id, sizeof(com_dev->tx_msg_buffer));
+	}
+
+	return 0;
+}
+
+uint16_t PIOS_COM_MSG_Receive(uint32_t com_id, uint8_t * msg, uint16_t msg_len)
+{
+	PIOS_Assert(msg);
+	PIOS_Assert(msg_len);
+
+	struct pios_com_msg_dev * com_dev = (struct pios_com_msg_dev *)com_id;
+
+	PIOS_Assert(msg_len == sizeof(com_dev->rx_msg_buffer));
+
+	if (!com_dev->rx_msg_full) {
+		/* There's room in our buffer, kick the receiver */
+		(com_dev->driver->rx_start)(com_dev->lower_id, sizeof(com_dev->rx_msg_buffer));
+	} else {
+		memcpy(msg, com_dev->rx_msg_buffer, msg_len);
+		com_dev->rx_msg_full = false;
+
+		return msg_len;
+	}
+
+	return 0;
+}
+
+#endif	/* PIOS_INCLUDE_COM_MSG */
+
+/**
+ * @}
+ * @}
+ */
diff --git a/flight/PiOS/STM32F10x/pios_usb_hid.c b/flight/PiOS/STM32F10x/pios_usb_hid.c
index 11eb988c1..e70c93046 100644
--- a/flight/PiOS/STM32F10x/pios_usb_hid.c
+++ b/flight/PiOS/STM32F10x/pios_usb_hid.c
@@ -207,9 +207,15 @@ static void PIOS_USB_HID_RxStart(uint32_t usbhid_id, uint16_t rx_bytes_avail) {
 	}
 
 	// If endpoint was stalled and there is now space make it valid
+#ifdef PIOS_USB_BOARD_BL_HID_HAS_NO_LENGTH_BYTE
+	uint16_t max_payload_length = PIOS_USB_BOARD_HID_DATA_LENGTH - 1;
+#else
+	uint16_t max_payload_length = PIOS_USB_BOARD_HID_DATA_LENGTH - 2;
+#endif
+
 	PIOS_IRQ_Disable();
 	if ((GetEPRxStatus(usb_hid_dev->cfg->data_rx_ep) != EP_RX_VALID) && 
-	    (rx_bytes_avail >= PIOS_USB_BOARD_HID_DATA_LENGTH)) {
+	    (rx_bytes_avail >= max_payload_length)) {
 		SetEPRxStatus(usb_hid_dev->cfg->data_rx_ep, EP_RX_VALID);
 	}
 	PIOS_IRQ_Enable();
@@ -328,7 +334,15 @@ static void PIOS_USB_HID_EP_OUT_Callback(void)
 				&headroom,
 				&need_yield);
 #endif
-	if (headroom >= PIOS_USB_BOARD_HID_DATA_LENGTH) {
+
+#ifdef PIOS_USB_BOARD_BL_HID_HAS_NO_LENGTH_BYTE
+	uint16_t max_payload_length = PIOS_USB_BOARD_HID_DATA_LENGTH - 1;
+#else
+	uint16_t max_payload_length = PIOS_USB_BOARD_HID_DATA_LENGTH - 2;
+#endif
+
+	if (headroom >= max_payload_length) {
+
 		/* We have room for a maximum length message */
 		SetEPRxStatus(usb_hid_dev->cfg->data_rx_ep, EP_RX_VALID);
 	} else {
diff --git a/flight/PiOS/inc/pios_com.h b/flight/PiOS/inc/pios_com.h
index 19abb2f27..10591f116 100644
--- a/flight/PiOS/inc/pios_com.h
+++ b/flight/PiOS/inc/pios_com.h
@@ -31,6 +31,9 @@
 #ifndef PIOS_COM_H
 #define PIOS_COM_H
 
+#include <stdint.h>		/* uint*_t */
+#include <stdbool.h>		/* bool */
+
 typedef uint16_t (*pios_com_callback)(uint32_t context, uint8_t * buf, uint16_t buf_len, uint16_t * headroom, bool * task_woken);
 
 struct pios_com_driver {
@@ -43,7 +46,6 @@ struct pios_com_driver {
 };
 
 /* Public Functions */
-extern int32_t PIOS_COM_Init(uint32_t * com_id, const struct pios_com_driver * driver, uint32_t lower_id, uint8_t * rx_buffer, uint16_t rx_buffer_len, uint8_t * tx_buffer, uint16_t tx_buffer_len);
 extern int32_t PIOS_COM_ChangeBaud(uint32_t com_id, uint32_t baud);
 extern int32_t PIOS_COM_SendCharNonBlocking(uint32_t com_id, char c);
 extern int32_t PIOS_COM_SendChar(uint32_t com_id, char c);
diff --git a/flight/PiOS/inc/pios_com_msg.h b/flight/PiOS/inc/pios_com_msg.h
new file mode 100644
index 000000000..1caaeabeb
--- /dev/null
+++ b/flight/PiOS/inc/pios_com_msg.h
@@ -0,0 +1,45 @@
+/**
+ ******************************************************************************
+ * @addtogroup PIOS PIOS Core hardware abstraction layer
+ * @{
+ * @addtogroup PIOS_COM COM MSG layer functions
+ * @brief Hardware communication layer
+ * @{
+ *
+ * @file       pios_com_msg.h  
+ * @author     The OpenPilot Team, http://www.openpilot.org Copyright (C) 2010.
+ * @brief      COM MSG layer functions header
+ * @see        The GNU Public License (GPL) Version 3
+ *
+ *****************************************************************************/
+/* 
+ * This program is free software; you can redistribute it and/or modify 
+ * it under the terms of the GNU General Public License as published by 
+ * the Free Software Foundation; either version 3 of the License, or 
+ * (at your option) any later version.
+ * 
+ * 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.
+ * 
+ * You should have received a copy of the GNU General Public License along 
+ * with this program; if not, write to the Free Software Foundation, Inc., 
+ * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ */
+
+#ifndef PIOS_COM_MSG_H
+#define PIOS_COM_MSG_H
+
+#include <stdint.h>		/* uint*_t */
+
+/* Public Functions */
+extern int32_t PIOS_COM_MSG_Send(uint32_t com_id, const uint8_t *msg, uint16_t msg_len);
+extern uint16_t PIOS_COM_MSG_Receive(uint32_t com_id, uint8_t * buf, uint16_t buf_len);
+
+#endif /* PIOS_COM_MSG_H */
+
+/**
+  * @}
+  * @}
+  */
diff --git a/flight/PiOS/inc/pios_com_msg_priv.h b/flight/PiOS/inc/pios_com_msg_priv.h
new file mode 100644
index 000000000..20992de47
--- /dev/null
+++ b/flight/PiOS/inc/pios_com_msg_priv.h
@@ -0,0 +1,44 @@
+/**
+ ******************************************************************************
+ * @addtogroup PIOS PIOS Core hardware abstraction layer
+ * @{
+ * @addtogroup PIOS_COM COM MSG layer functions
+ * @brief Hardware communication layer
+ * @{
+ *
+ * @file       pios_com_msg_priv.h
+ * @author     The OpenPilot Team, http://www.openpilot.org Copyright (C) 2010.
+ * @brief      COM MSG private definitions.
+ * @see        The GNU Public License (GPL) Version 3
+ *
+ *****************************************************************************/
+/*
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * 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.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ */
+
+#ifndef PIOS_COM_MSG_PRIV_H
+#define PIOS_COM_MSG_PRIV_H
+
+#include <stdint.h>		/* uint*_t */
+#include "pios_com_priv.h"	/* struct pios_com_driver */
+
+extern int32_t PIOS_COM_MSG_Init(uint32_t * com_id, const struct pios_com_driver * driver, uint32_t lower_id);
+
+#endif /* PIOS_COM_MSG_PRIV_H */
+
+/**
+  * @}
+  * @}
+  */
diff --git a/flight/PiOS/inc/pios_com_priv.h b/flight/PiOS/inc/pios_com_priv.h
index 7bd9a9be0..c39522f79 100644
--- a/flight/PiOS/inc/pios_com_priv.h
+++ b/flight/PiOS/inc/pios_com_priv.h
@@ -31,6 +31,8 @@
 #ifndef PIOS_COM_PRIV_H
 #define PIOS_COM_PRIV_H
 
+extern int32_t PIOS_COM_Init(uint32_t * com_id, const struct pios_com_driver * driver, uint32_t lower_id, uint8_t * rx_buffer, uint16_t rx_buffer_len, uint8_t * tx_buffer, uint16_t tx_buffer_len);
+
 #endif /* PIOS_COM_PRIV_H */
 
 /**