diff --git a/bacnet-stack/ports/bdk-atxx4-mstp/Makefile b/bacnet-stack/ports/bdk-atxx4-mstp/Makefile
index db7d1a0c..74b8cb83 100644
--- a/bacnet-stack/ports/bdk-atxx4-mstp/Makefile
+++ b/bacnet-stack/ports/bdk-atxx4-mstp/Makefile
@@ -52,7 +52,7 @@ ifeq (${JTAG},jtag2fast)
 AVRDUDE_PROGRAMMERID = jtag2fast
 endif
 ifndef JTAG
-AVRDUDE_PROGRAMMERID = jtag2fast
+AVRDUDE_PROGRAMMERID = dragon_jtag
 endif
 #
 # port--serial or parallel port to which your
@@ -171,6 +171,12 @@ ifeq (${SEEPROM},128)
 DEFINES += -DSEEPROM_PAGE_SIZE=64
 DEFINES += -DSEEPROM_WORD_ADDRESS_16BIT=1
 endif
+ifeq (${BDK_VERSION},3)
+DEFINES += -DBDK_VERSION=3
+endif
+
+#ifdef
+
 
 OPTIMIZE_FLAGS = -mcall-prologues
 OPTIMIZE_FLAGS += -finline-functions-called-once
diff --git a/bacnet-stack/ports/bdk-atxx4-mstp/led.c b/bacnet-stack/ports/bdk-atxx4-mstp/led.c
index a906ace2..29e6b55e 100644
--- a/bacnet-stack/ports/bdk-atxx4-mstp/led.c
+++ b/bacnet-stack/ports/bdk-atxx4-mstp/led.c
@@ -26,6 +26,10 @@
 #include "timer.h"
 #include "led.h"
 
+#ifndef BDK_VERSION
+#define BDK_VERSION 4
+#endif
+
 static struct itimer Off_Delay_Timer[MAX_LEDS];
 
 /*************************************************************************
@@ -44,10 +48,18 @@ void led_on(
             BIT_SET(PORTD, PD6);
             break;
         case 2:
+#if (BDK_VERSION==4)
+            BIT_SET(PORTB, PB0);
+#else
             BIT_SET(PORTC, PC7);
+#endif
             break;
         case 3:
+#if (BDK_VERSION==4)
+            BIT_SET(PORTB, PB4);
+#else
             BIT_SET(PORTC, PC6);
+#endif
             break;
         default:
             break;
@@ -73,10 +85,18 @@ void led_off(
             BIT_CLEAR(PORTD, PD6);
             break;
         case 2:
+#if (BDK_VERSION==4)
+            BIT_CLEAR(PORTB, PB0);
+#else
             BIT_CLEAR(PORTC, PC7);
+#endif
             break;
         case 3:
+#if (BDK_VERSION==4)
+            BIT_CLEAR(PORTB, PB4);
+#else
             BIT_CLEAR(PORTC, PC6);
+#endif
             break;
         default:
             break;
@@ -100,9 +120,17 @@ bool led_state(
         case 1:
             return (BIT_CHECK(PIND, PIND6));
         case 2:
+#if (BDK_VERSION==4)
+            return (BIT_CHECK(PINB, PINC0));
+#else
             return (BIT_CHECK(PINC, PINC7));
+#endif
         case 3:
+#if (BDK_VERSION==4)
+            return (BIT_CHECK(PINB, PINC4));
+#else
             return (BIT_CHECK(PINC, PINC6));
+#endif
         default:
             break;
     }
@@ -183,10 +211,15 @@ void led_init(
     uint8_t i;  /* loop counter */
 
     /* configure the port pins as outputs */
-    BIT_SET(DDRC, DDC7);
-    BIT_SET(DDRC, DDC6);
     BIT_SET(DDRD, DDD7);
     BIT_SET(DDRD, DDD6);
+#if (BDK_VERSION==4)
+    BIT_SET(DDRB, DDB0);
+    BIT_SET(DDRB, DDB4);
+#else
+    BIT_SET(DDRC, DDC7);
+    BIT_SET(DDRC, DDC6);
+#endif
     for (i = 0; i < MAX_LEDS; i++) {
         led_on_interval(i, 500);
     }
diff --git a/bacnet-stack/ports/bdk-atxx4-mstp/test.c b/bacnet-stack/ports/bdk-atxx4-mstp/test.c
index 6689e4c7..d9d147be 100644
--- a/bacnet-stack/ports/bdk-atxx4-mstp/test.c
+++ b/bacnet-stack/ports/bdk-atxx4-mstp/test.c
@@ -37,6 +37,10 @@
 /* me */
 #include "test.h"
 
+#ifndef BDK_VERSION
+#define BDK_VERSION 4
+#endif
+
 /* timer for test task */
 static struct itimer Test_Timer;
 /* MAC Address of MS/TP */
@@ -52,7 +56,11 @@ void test_init(
 #endif
     timer_interval_start_seconds(&Test_Timer, 1);
     /* configure a port pin as output */
+#if (BDK_VERSION==4)
+    BIT_SET(DDRD, DDB5);
+#else
     BIT_SET(DDRB, DDB0);
+#endif
 }
 
 /*************************************************************************
@@ -63,7 +71,11 @@ void test_init(
 static inline void test_pin_on(
     void)
 {
+#if (BDK_VERSION==4)
+    BIT_SET(PORTD, PD5);
+#else
     BIT_SET(PORTB, PB0);
+#endif
 }
 
 /*************************************************************************
@@ -74,7 +86,11 @@ static inline void test_pin_on(
 static inline void test_pin_off(
     void)
 {
+#if (BDK_VERSION==4)
+    BIT_CLEAR(PORTD, PD5);
+#else
     BIT_CLEAR(PORTB, PB0);
+#endif
 }
 
 /*************************************************************************
@@ -85,7 +101,11 @@ static inline void test_pin_off(
 static inline bool test_pin_state(
     void)
 {
+#if (BDK_VERSION==4)
+    return (BIT_CHECK(PIND, PD5));
+#else
     return (BIT_CHECK(PINB, PB0));
+#endif
 }
 
 /*************************************************************************