diff --git a/bacnet-stack/ports/atmega168/bacnet.ewp b/bacnet-stack/ports/atmega168/bacnet.ewp
index 5d995186..9716296a 100644
--- a/bacnet-stack/ports/atmega168/bacnet.ewp
+++ b/bacnet-stack/ports/atmega168/bacnet.ewp
@@ -63,7 +63,7 @@
         </option>
         <option>
           <name>SCCStackSize</name>
-          <state>0xff</state>
+          <state>0x200</state>
         </option>
         <option>
           <name>SCExtCStack</name>
@@ -239,7 +239,7 @@
         <option>
           <name>CCDefines</name>
           <state>BACDL_MSTP</state>
-          <state>MAX_APDU=128</state>
+          <state>MAX_APDU=50</state>
           <state>BIG_ENDIAN=0</state>
           <state>MAX_TSM_TRANSACTIONS=0</state>
           <state>BACAPP_REAL</state>
@@ -247,6 +247,7 @@
           <state>BACAPP_ENUMERATED</state>
           <state>BACAPP_CHARACTER_STRING</state>
           <state>BACAPP_OBJECT_ID</state>
+          <state>WRITE_PROPERTY</state>
         </option>
         <option>
           <name>CCPreprocFile</name>
@@ -1953,6 +1954,9 @@
   <file>
     <name>$PROJ_DIR$\avr035.h</name>
   </file>
+  <file>
+    <name>$PROJ_DIR$\..\..\src\bacapp.c</name>
+  </file>
   <file>
     <name>$PROJ_DIR$\..\..\src\bacdcode.c</name>
   </file>
@@ -2031,6 +2035,9 @@
   <file>
     <name>$PROJ_DIR$\..\..\src\whois.c</name>
   </file>
+  <file>
+    <name>$PROJ_DIR$\..\..\src\wp.c</name>
+  </file>
 </project>
 
 
diff --git a/bacnet-stack/ports/atmega168/hardware.h b/bacnet-stack/ports/atmega168/hardware.h
index a402590c..19bf3364 100644
--- a/bacnet-stack/ports/atmega168/hardware.h
+++ b/bacnet-stack/ports/atmega168/hardware.h
@@ -43,6 +43,9 @@
 #define LED_NPDU_INIT() BIT_SET(DDRD, DDD5)
 #define LED_NPDU_ON() BIT_CLEAR(PORTD, PD5)
 #define LED_NPDU_OFF() BIT_SET(PORTD, PD5)
+/* #define LED_NPDU PORTD_Bit5 */
+/* #define LED_NPDU_OFF() {LED_NPDU = false;} */
+/* #define LED_NPDU_ON() {LED_NPDU = true;} */
 
 #define LED_GREEN_INIT() BIT_SET(DDRD, DDD4)
 #define LED_GREEN_ON() BIT_CLEAR(PORTD, PD4)
diff --git a/bacnet-stack/ports/atmega168/iar2gcc.h b/bacnet-stack/ports/atmega168/iar2gcc.h
index e3779651..3a051408 100644
--- a/bacnet-stack/ports/atmega168/iar2gcc.h
+++ b/bacnet-stack/ports/atmega168/iar2gcc.h
@@ -42,6 +42,7 @@
 #if defined(__IAR_SYSTEMS_ICC__) || defined(__IAR_SYSTEMS_ASM__)
 #include <inavr.h>
 #include <ioavr.h>
+/* BitValue is used alot in GCC examples */
 #define _BV(bit_num) (1 << (bit_num))
 
 /* inline function */
@@ -52,13 +53,11 @@ static inline void _delay_us(
         __delay_cycles(F_CPU / 1000000UL);
     } while (microseconds--);
 }
+#endif
 
-#else
-/* GCC */
+/* Input/Output Registers */
+#if defined(__GNUC__)
 #include <avr/io.h>
-#include <avr/interrupt.h>
-#include <util/delay.h>
-#include <avr/eeprom.h>
 
 typedef struct {
     unsigned char bit0:1;
@@ -182,18 +181,46 @@ typedef struct {
 #define GPIOR2_Bit6 GPIO_BITREG(GPIOR2,6)
 #define GPIOR2_Bit7 GPIO_BITREG(GPIOR2,7)
 
-    /* FIXME: intrinsic routines: map to assembler for size/speed */
-#define __multiply_unsigned(x,y) ((x)*(y))
+#endif
 
-
-    /* memory location */
-#define __eeprom __attribute__((section (".eeprom")))
-#define __flash  __attribute__((progmem))
-    /* __root means to not optimize or strip */
-#define __root
+/* Global Interrupts */
+#if defined(__GNUC__)
 #define __enable_interrupt() sei()
 #define __disable_interrupt() cli()
+#endif
 
+/* Interrupts */
+#if defined(__ICCAVR__)
+#define PRAGMA(x) _Pragma( #x )
+#define ISR(vec) PRAGMA( vector=vec ) __interrupt void handler_##vec(void)
+#endif
+#if defined(__GNUC__)
+#include <avr/interrupt.h>
+#endif
+
+/* Flash */
+#if defined(__ICCAVR__)
+#define FLASH_DECLARE(x) __flash x
+#endif
+#if defined(__GNUC__)
+#define FLASH_DECLARE(x) x __attribute__((__progmem__))
+#endif
+
+/* EEPROM */
+#if defined(__ICCAVR__)
+#define EEPROM_DECLARE(x) __eeprom x
+#endif
+#if defined(__GNUC__)
+#include <avr/eeprom.h>
+#define EEPROM_DECLARE(x) x __attribute__((section (".eeprom")))
+#endif
+
+/* IAR intrinsic routines */
+#if defined(__GNUC__)
+    /* FIXME: intrinsic routines: map to assembler for size/speed */
+    #define __multiply_unsigned(x,y) ((x)*(y))
+    /* FIXME: __root means to not optimize or strip */
+    #define __root
 #endif
 
 #endif
diff --git a/bacnet-stack/ports/atmega168/main.c b/bacnet-stack/ports/atmega168/main.c
index 01cb0ac0..c6e4598b 100644
--- a/bacnet-stack/ports/atmega168/main.c
+++ b/bacnet-stack/ports/atmega168/main.c
@@ -138,6 +138,63 @@ static void input_switch_read(
     }
 }
 
+/* stack checking */
+#if STACK_CHECK_ENABLED
+#if defined(__GNUC__)
+extern uint8_t _end;
+extern uint8_t __stack;
+#define STACK_CANARY (0xC5)
+void StackPaint(void) __attribute__ ((naked)) __attribute__ ((section (".init1")));
+
+void StackPaint(void)
+{
+#if 0
+    uint8_t *p = &_end;
+
+    while(p <= &__stack)
+    {
+        *p = STACK_CANARY;
+        p++;
+    }
+#else
+    __asm volatile ("    ldi r30,lo8(_end)\n"
+                    "    ldi r31,hi8(_end)\n"
+                    "    ldi r24,lo8(0xc5)\n" /* STACK_CANARY = 0xc5 */
+                    "    ldi r25,hi8(__stack)\n"
+                    "    rjmp .cmp\n"
+                    ".loop:\n"
+                    "    st Z+,r24\n"
+                    ".cmp:\n"
+                    "    cpi r30,lo8(__stack)\n"
+                    "    cpc r31,r25\n"
+                    "    brlo .loop\n"
+                    "    breq .loop"::);
+#endif
+}
+
+static uint16_t StackCount(void)
+{
+    const uint8_t *p = &_end;
+    uint16_t       c = 0;
+
+    while(*p == STACK_CANARY && p <= &__stack)
+    {
+        p++;
+        c++;
+    }
+
+    return c;
+}
+
+static void Analog_Value_Task(void)
+{
+    extern float AV_Present_Value[MAX_ANALOG_VALUES];
+    
+    AV_Present_Value[0] = (float)StackCount();
+}
+#endif
+#endif
+
 static uint8_t PDUBuffer[MAX_MPDU];
 int main(
     void)
@@ -159,6 +216,9 @@ int main(
         /* BACnet handling */
         pdu_len = datalink_receive(&src, &PDUBuffer[0], sizeof(PDUBuffer), 0);
         if (pdu_len) {
+#if STACK_CHECK_ENABLED
+            Analog_Value_Task();
+#endif
             LED_NPDU_ON();
             npdu_handler(&src, &PDUBuffer[0], pdu_len);
             LED_NPDU_OFF();
diff --git a/bacnet-stack/ports/atmega168/rs485.c b/bacnet-stack/ports/atmega168/rs485.c
index 5946ff15..40bc9e2a 100644
--- a/bacnet-stack/ports/atmega168/rs485.c
+++ b/bacnet-stack/ports/atmega168/rs485.c
@@ -237,17 +237,18 @@ void RS485_Send_Data(
         while (!BIT_CHECK(UCSR0A, UDRE0)) {
             /* do nothing - wait until Tx buffer is empty */
         }
+        /* Send the data byte */
         UDR0 = *buffer;
         buffer++;
         nbytes--;
     }
-    /* Clear the Transmit Complete flag by writing a one to it. */
-    BIT_SET(UCSR0A, TXC0);
     /* was the frame sent? */
     while (!BIT_CHECK(UCSR0A, TXC0)) {
         /* do nothing - wait until the entire frame in the
            Transmit Shift Register has been shifted out */
     }
+    /* Clear the Transmit Complete flag by writing a one to it. */
+    BIT_SET(UCSR0A, TXC0);
     /* per MSTP spec, sort of */
     Timer_Silence_Reset();
 }
diff --git a/bacnet-stack/ports/atmega168/timer.c b/bacnet-stack/ports/atmega168/timer.c
index 51fcff4b..40c60b12 100644
--- a/bacnet-stack/ports/atmega168/timer.c
+++ b/bacnet-stack/ports/atmega168/timer.c
@@ -71,13 +71,7 @@ void Timer_Initialize(
 /* Timer interupt */
 /* note: Global interupts must be enabled - sei() */
 /* Timer Overflowed!  Increment the time. */
-#if defined(__IAR_SYSTEMS_ICC__) || defined(__IAR_SYSTEMS_ASM__)
-#pragma vector=TIMER0_OVF_vect
-__interrupt void myTIMER0_OVF_vect(
-    )
-#else
 ISR(TIMER0_OVF_vect)
-#endif
 {
     /* Set the counter for the next interrupt */
     TCNT0 = TIMER_COUNT;