diff --git a/ADF7021.h b/ADF7021.h
index cb355db..81fe166 100644
--- a/ADF7021.h
+++ b/ADF7021.h
@@ -2,6 +2,9 @@
  *   Copyright (C) 2016 by Jim McLaughlin KI6ZUM
  *   Copyright (C) 2016, 2017 by Andy Uribe CA6JAU
  *
+ *   Some of the code is based on work of Guus Van Dooren PE1PLM:
+ *   https://github.com/ki6zum/gmsk-dstar/blob/master/firmware/dvmega/dvmega.ino
+ *
  *   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 2 of the License, or
diff --git a/BitRB.cpp b/BitRB.cpp
index 8faee51..891d3dc 100644
--- a/BitRB.cpp
+++ b/BitRB.cpp
@@ -1,6 +1,7 @@
 /*
 TX fifo control - Copyright (C) KI6ZUM 2015
 Copyright (C) 2015,2016 by Jonathan Naylor G4KLX
+Copyright (C) 2016, 2017 by Andy Uribe CA6JAU
 
 This library is free software; you can redistribute it and/or
 modify it under the terms of the GNU Library General Public
diff --git a/BitRB.h b/BitRB.h
index 0a9c952..3b191b2 100644
--- a/BitRB.h
+++ b/BitRB.h
@@ -1,7 +1,8 @@
 /*
 Serial fifo control - Copyright (C) KI6ZUM 2015
 Copyright (C) 2015,2016 by Jonathan Naylor G4KLX
-
+Copyright (C) 2016, 2017 by Andy Uribe CA6JAU
+ 
 This library is free software; you can redistribute it and/or
 modify it under the terms of the GNU Library General Public
 License as published by the Free Software Foundation; either
diff --git a/Config.h b/Config.h
index dd726db..8201462 100644
--- a/Config.h
+++ b/Config.h
@@ -19,11 +19,14 @@
 #if !defined(CONFIG_H)
 #define  CONFIG_H
 
+// Enable ADF7021 support:
 #define  ADF7021
 
+// Host communication selection:
 //#define STM32_USART1_HOST
 #define STM32_USB_HOST
 
-//#define SERIAL_REPEATER
+// Enable Nextion LCD serial port repeater:
+#define SERIAL_REPEATER
 
 #endif
diff --git a/DMRDMORX.cpp b/DMRDMORX.cpp
index abbec8c..ea942de 100644
--- a/DMRDMORX.cpp
+++ b/DMRDMORX.cpp
@@ -1,5 +1,6 @@
 /*
  *   Copyright (C) 2009-2016 by Jonathan Naylor G4KLX
+ *   Copyright (C) 2016, 2017 by Andy Uribe CA6JAU
  *
  *   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
diff --git a/DMRDMORX.h b/DMRDMORX.h
index 8afcb91..0a549f3 100644
--- a/DMRDMORX.h
+++ b/DMRDMORX.h
@@ -1,5 +1,6 @@
 /*
  *   Copyright (C) 2015,2016 by Jonathan Naylor G4KLX
+ *   Copyright (C) 2016, 2017 by Andy Uribe CA6JAU
  *
  *   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
diff --git a/DMRDMOTX.cpp b/DMRDMOTX.cpp
index 093b660..6f77627 100644
--- a/DMRDMOTX.cpp
+++ b/DMRDMOTX.cpp
@@ -1,6 +1,7 @@
 /*
  *   Copyright (C) 2009-2016 by Jonathan Naylor G4KLX
  *   Copyright (C) 2016 by Colin Durbridge G4EML
+ *   Copyright (C) 2016, 2017 by Andy Uribe CA6JAU
  *
  *   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
diff --git a/DMRDMOTX.h b/DMRDMOTX.h
index 84234af..ce8459a 100644
--- a/DMRDMOTX.h
+++ b/DMRDMOTX.h
@@ -1,6 +1,7 @@
 /*
  *   Copyright (C) 2015,2016 by Jonathan Naylor G4KLX
  *   Copyright (C) 2016 by Colin Durbridge G4EML
+ *   Copyright (C) 2016, 2017 by Andy Uribe CA6JAU
  *
  *   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
diff --git a/DStarRX.cpp b/DStarRX.cpp
index 56ca601..04e1ae3 100644
--- a/DStarRX.cpp
+++ b/DStarRX.cpp
@@ -1,5 +1,6 @@
 /*
  *   Copyright (C) 2009-2016 by Jonathan Naylor G4KLX
+ *   Copyright (C) 2016, 2017 by Andy Uribe CA6JAU
  *
  *   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
diff --git a/DStarRX.h b/DStarRX.h
index 2490c37..34404fd 100644
--- a/DStarRX.h
+++ b/DStarRX.h
@@ -1,5 +1,6 @@
 /*
  *   Copyright (C) 2015,2016 by Jonathan Naylor G4KLX
+ *   Copyright (C) 2016, 2017 by Andy Uribe CA6JAU
  *
  *   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
diff --git a/DStarTX.cpp b/DStarTX.cpp
index d4fda70..e5670f6 100644
--- a/DStarTX.cpp
+++ b/DStarTX.cpp
@@ -1,5 +1,6 @@
 /*
  *   Copyright (C) 2009-2016 by Jonathan Naylor G4KLX
+ *   Copyright (C) 2016, 2017 by Andy Uribe CA6JAU
  *
  *   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
diff --git a/DStarTX.h b/DStarTX.h
index 5f3957f..ee7666c 100644
--- a/DStarTX.h
+++ b/DStarTX.h
@@ -1,5 +1,6 @@
 /*
  *   Copyright (C) 2015,2016 by Jonathan Naylor G4KLX
+ *   Copyright (C) 2016, 2017 by Andy Uribe CA6JAU
  *
  *   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
diff --git a/Globals.h b/Globals.h
index 1e01060..bf3b072 100644
--- a/Globals.h
+++ b/Globals.h
@@ -1,5 +1,6 @@
 /*
  *   Copyright (C) 2015,2016 by Jonathan Naylor G4KLX
+ *   Copyright (C) 2016, 2017 by Andy Uribe CA6JAU
  *
  *   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
diff --git a/IO.cpp b/IO.cpp
index 79541ff..d2a1eed 100644
--- a/IO.cpp
+++ b/IO.cpp
@@ -78,6 +78,9 @@ void CIO::process()
 void CIO::interrupt()
 {
   uint8_t bit = 0;
+  
+  if (!m_started)
+    return;
 
   if(m_tx) {
     m_txBuffer.get(bit);
@@ -98,6 +101,23 @@ void CIO::interrupt()
 
 }
 
+void CIO::start()
+{ 
+  if (m_started)
+    return;
+  
+  ifConf();
+  
+  delay_rx();
+  setRX();
+  
+  startInt();
+    
+  m_started = true;
+  
+  setMode();
+}
+
 void CIO::write(uint8_t* data, uint16_t length)
 {
   if (!m_started)
diff --git a/IO.h b/IO.h
index 3f66c61..c8fdd8c 100644
--- a/IO.h
+++ b/IO.h
@@ -71,7 +71,8 @@ public:
   void  setTX();
   void  setRX();
   void  ifConf();
-  void  ifInit();
+  void  start();
+  void  startInt();
 
   // Misc functions
   void  dlybit(void);
diff --git a/IOArduino.cpp b/IOArduino.cpp
index fdd72ff..381a467 100644
--- a/IOArduino.cpp
+++ b/IOArduino.cpp
@@ -99,21 +99,16 @@ void CIO::Init()
   pinMode(PIN_P25_LED, OUTPUT);
   pinMode(PIN_PTT_LED, OUTPUT);
   pinMode(PIN_COS_LED, OUTPUT);
+
 }
 
-void CIO::ifInit()
+void CIO::startInt()
 {
-  m_started = true;
-
 #if defined (__STM32F1__)
   attachInterrupt(PIN_TXRX_CLK, EXT_IRQHandler, RISING);
 #else
   attachInterrupt(digitalPinToInterrupt(PIN_TXRX_CLK), EXT_IRQHandler, RISING);
 #endif
- 
-  ifConf();
-  delay_rx();;
-  setRX();
 }
 
 void CIO::SCLK_pin(bool on) 
diff --git a/IOSTM.cpp b/IOSTM.cpp
index 2af5d45..e6e95c5 100644
--- a/IOSTM.cpp
+++ b/IOSTM.cpp
@@ -92,7 +92,7 @@ void CIO::dlybit(void)
 }
 
 void CIO::Init()
-{
+{ 
   // USB Conf IO:
   RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA | RCC_APB2Periph_GPIOB | RCC_APB2Periph_GPIOC | RCC_APB2Periph_AFIO, ENABLE);
   GPIO_PinRemapConfig(GPIO_Remap_SWJ_JTAGDisable, ENABLE);
@@ -101,6 +101,8 @@ void CIO::Init()
   RCC_APB1PeriphClockCmd(RCC_APB1Periph_USB, ENABLE);
   NVIC_PriorityGroupConfig(NVIC_PriorityGroup_1);
 
+  EXTI_InitTypeDef EXTI_InitStructure;
+
   GPIO_InitTypeDef GPIO_InitStruct;
   GPIO_StructInit(&GPIO_InitStruct);
 
@@ -201,14 +203,6 @@ void CIO::Init()
   GPIO_InitStruct.GPIO_Pin   = PIN_COS_LED;
   GPIO_InitStruct.GPIO_Mode  = GPIO_Mode_Out_PP;
   GPIO_Init(PORT_COS_LED, &GPIO_InitStruct);
-}
-
-void CIO::ifInit()
-{
-  EXTI_InitTypeDef EXTI_InitStructure;
-  NVIC_InitTypeDef NVIC_InitStructure;
-
-  m_started = true;
 
   // Connect EXTI15 Line
   GPIO_EXTILineConfig(PORT_TXRX_CLK_INT, PIN_TXRX_CLK_INT);
@@ -220,16 +214,18 @@ void CIO::ifInit()
   EXTI_InitStructure.EXTI_LineCmd = ENABLE;
   EXTI_Init(&EXTI_InitStructure);
 
+}
+
+void CIO::startInt()
+{
+  NVIC_InitTypeDef NVIC_InitStructure;
+  
   // Enable and set EXTI15 Interrupt
   NVIC_InitStructure.NVIC_IRQChannel = EXTI15_10_IRQn;
   NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 0;
   NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0;
   NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
   NVIC_Init(&NVIC_InitStructure);
-
-  ifConf();
-  delay_rx();;
-  setRX();
 }
 
 void CIO::SCLK_pin(bool on)
diff --git a/MMDVM_HS.cpp b/MMDVM_HS.cpp
index ccf2fef..2dcdae0 100644
--- a/MMDVM_HS.cpp
+++ b/MMDVM_HS.cpp
@@ -2,6 +2,7 @@
  *   Copyright (C) 2015,2016 by Jonathan Naylor G4KLX
  *   Copyright (C) 2016 by Mathis Schmieder DB9MAT
  *   Copyright (C) 2016 by Colin Durbridge G4EML
+ *   Copyright (C) 2016, 2017 by Andy Uribe CA6JAU
  *
  *   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
diff --git a/MMDVM_HS.ino b/MMDVM_HS.ino
index 74214ff..9bd112b 100644
--- a/MMDVM_HS.ino
+++ b/MMDVM_HS.ino
@@ -1,6 +1,7 @@
 /*
  *   Copyright (C) 2015,2016 by Jonathan Naylor G4KLX
  *   Copyright (C) 2016 by Colin Durbridge G4EML
+ *   Copyright (C) 2016, 2017 by Andy Uribe CA6JAU
  *
  *   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
diff --git a/P25RX.cpp b/P25RX.cpp
index 0739b61..77c1343 100644
--- a/P25RX.cpp
+++ b/P25RX.cpp
@@ -1,5 +1,6 @@
 /*
  *   Copyright (C) 2016,2017 by Jonathan Naylor G4KLX
+ *   Copyright (C) 2016, 2017 by Andy Uribe CA6JAU
  *
  *   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
diff --git a/P25RX.h b/P25RX.h
index 514ad95..611b18d 100644
--- a/P25RX.h
+++ b/P25RX.h
@@ -1,5 +1,6 @@
 /*
  *   Copyright (C) 2015,2016,2017 by Jonathan Naylor G4KLX
+ *   Copyright (C) 2016, 2017 by Andy Uribe CA6JAU
  *
  *   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
diff --git a/P25TX.cpp b/P25TX.cpp
index 781c207..b1bff2e 100644
--- a/P25TX.cpp
+++ b/P25TX.cpp
@@ -1,5 +1,6 @@
 /*
  *   Copyright (C) 2016 by Jonathan Naylor G4KLX
+ *   Copyright (C) 2016, 2017 by Andy Uribe CA6JAU
  *
  *   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
diff --git a/P25TX.h b/P25TX.h
index 1f239ce..bd14c7c 100644
--- a/P25TX.h
+++ b/P25TX.h
@@ -1,5 +1,6 @@
 /*
  *   Copyright (C) 2016,2017 by Jonathan Naylor G4KLX
+ *   Copyright (C) 2016, 2017 by Andy Uribe CA6JAU
  *
  *   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
diff --git a/SerialArduino.cpp b/SerialArduino.cpp
old mode 100755
new mode 100644
index f3334f2..c2c4c8d
--- a/SerialArduino.cpp
+++ b/SerialArduino.cpp
@@ -1,5 +1,6 @@
 /*
  *   Copyright (C) 2016 by Jonathan Naylor G4KLX
+ *   Copyright (C) 2016, 2017 by Andy Uribe CA6JAU
  *
  *   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
@@ -27,14 +28,17 @@ void CSerialPort::beginInt(uint8_t n, int speed)
 {
   switch (n) {
     case 1U:
+    #if defined(STM32_USART1_HOST) && defined(__STM32F1__)
+      Serial1.begin(speed);
+    #else
       Serial.begin(speed);
+    #endif
       break;
-/*    case 2U:
+    case 3U:
+    #if defined(SERIAL_REPEATER) && defined(__STM32F1__)
       Serial2.begin(speed);
+    #endif
       break;
-    case 3U:
-      Serial3.begin(speed);
-      break;*/
     default:
       break;
   }
@@ -44,11 +48,15 @@ int CSerialPort::availableInt(uint8_t n)
 {
   switch (n) {
     case 1U:
+    #if defined(STM32_USART1_HOST) && defined(__STM32F1__)
+      return Serial1.available();
+    #else
       return Serial.available();
-/*    case 2U:
-      return Serial2.available();
+    #endif
     case 3U:
-      return Serial3.available();*/
+    #if defined(SERIAL_REPEATER) && defined(__STM32F1__)
+      return Serial2.available();
+    #endif
     default:
       return false;
   }
@@ -58,11 +66,15 @@ uint8_t CSerialPort::readInt(uint8_t n)
 {
   switch (n) {
     case 1U:
+    #if defined(STM32_USART1_HOST) && defined(__STM32F1__)
+      return Serial1.read();
+    #else
       return Serial.read();
-/*    case 2U:
-      return Serial2.read();
+    #endif
     case 3U:
-      return Serial3.read();*/
+    #if defined(SERIAL_REPEATER) && defined(__STM32F1__)
+      return Serial2.read();
+    #endif
     default:
       return 0U;
   }
@@ -72,20 +84,20 @@ void CSerialPort::writeInt(uint8_t n, const uint8_t* data, uint16_t length, bool
 {
   switch (n) {
     case 1U:
+    #if defined(STM32_USART1_HOST) && defined(__STM32F1__)
+      Serial1.write(data, length);
+      break;
+    #else
       Serial.write(data, length);
       if (flush)
         Serial.flush();
       break;
-/*    case 2U:
+    #endif
+    case 3U:
+    #if defined(SERIAL_REPEATER) && defined(__STM32F1__)
       Serial2.write(data, length);
-      if (flush)
-        Serial2.flush();
       break;
-    case 3U:
-      Serial3.write(data, length);
-      if (flush)
-        Serial3.flush();
-      break;*/
+    #endif
     default:
       break;
   }
diff --git a/SerialPort.cpp b/SerialPort.cpp
index 65b2e07..e240250 100644
--- a/SerialPort.cpp
+++ b/SerialPort.cpp
@@ -1,6 +1,7 @@
 /*
  *   Copyright (C) 2013,2015,2016 by Jonathan Naylor G4KLX
  *   Copyright (C) 2016 by Colin Durbridge G4EML
+ *   Copyright (C) 2016, 2017 by Andy Uribe CA6JAU
  *
  *   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
@@ -227,7 +228,7 @@ uint8_t CSerialPort::setConfig(const uint8_t* data, uint8_t length)
   
   dmrDMORX.setColorCode(colorCode);
 
-  io.ifInit();
+  io.start();
 
   return 0U;
 }
diff --git a/SerialSTM.cpp b/SerialSTM.cpp
index 2a54646..75f9309 100644
--- a/SerialSTM.cpp
+++ b/SerialSTM.cpp
@@ -41,11 +41,11 @@ USART2 - TXD PA2  - RXD PA3
 
 */
 
-#if defined(STM32_USART1_HOST)
-
 #define TX_SERIAL_FIFO_SIZE 256U
 #define RX_SERIAL_FIFO_SIZE 256U
 
+#if defined(STM32_USART1_HOST)
+
 extern "C" {
   void USART1_IRQHandler();
 }
@@ -174,8 +174,8 @@ void InitUSART1(int speed)
   // USART IRQ init
   NVIC_InitStructure.NVIC_IRQChannel    = USART1_IRQn;
   NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
-  NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 1;
-  NVIC_InitStructure.NVIC_IRQChannelSubPriority        = 1;
+  NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 2;
+  NVIC_InitStructure.NVIC_IRQChannelSubPriority        = 0;
   NVIC_Init(&NVIC_InitStructure);
 
   // Configure USART as alternate function
@@ -363,8 +363,8 @@ void InitUSART2(int speed)
   // USART IRQ init
   NVIC_InitStructure.NVIC_IRQChannel    = USART2_IRQn;
   NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
-  NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 1;
-  NVIC_InitStructure.NVIC_IRQChannelSubPriority        = 1;
+  NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 3;
+  NVIC_InitStructure.NVIC_IRQChannelSubPriority        = 0;
   NVIC_Init(&NVIC_InitStructure);
 
   // Configure USART as alternate function
@@ -498,7 +498,7 @@ void CSerialPort::writeInt(uint8_t n, const uint8_t* data, uint16_t length, bool
         usbserial.flush();
       break;
     #endif
-  #if defined(SERIAL_REPEATER)
+    #if defined(SERIAL_REPEATER)
     case 3U:
       WriteUSART2(data, length);
       if (flush)
diff --git a/YSFRX.cpp b/YSFRX.cpp
index a3e9a46..5079cd4 100644
--- a/YSFRX.cpp
+++ b/YSFRX.cpp
@@ -1,5 +1,6 @@
 /*
  *   Copyright (C) 2009-2017 by Jonathan Naylor G4KLX
+ *   Copyright (C) 2016, 2017 by Andy Uribe CA6JAU
  *
  *   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
diff --git a/YSFRX.h b/YSFRX.h
index 51c95fa..0cee0af 100644
--- a/YSFRX.h
+++ b/YSFRX.h
@@ -1,5 +1,6 @@
 /*
  *   Copyright (C) 2015,2016,2017 by Jonathan Naylor G4KLX
+ *   Copyright (C) 2016, 2017 by Andy Uribe CA6JAU
  *
  *   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
diff --git a/YSFTX.cpp b/YSFTX.cpp
index 8cbb58b..92829c1 100644
--- a/YSFTX.cpp
+++ b/YSFTX.cpp
@@ -1,5 +1,6 @@
 /*
  *   Copyright (C) 2009-2016 by Jonathan Naylor G4KLX
+ *   Copyright (C) 2016, 2017 by Andy Uribe CA6JAU
  *
  *   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
diff --git a/YSFTX.h b/YSFTX.h
index 21bd1a6..96f958f 100644
--- a/YSFTX.h
+++ b/YSFTX.h
@@ -1,5 +1,6 @@
 /*
  *   Copyright (C) 2015,2016,2017 by Jonathan Naylor G4KLX
+ *   Copyright (C) 2016, 2017 by Andy Uribe CA6JAU
  *
  *   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