diff --git a/bacnet-stack/ports/at91sam7s/dlmstp.c b/bacnet-stack/ports/at91sam7s/dlmstp.c
index b381bdaf..227e93ea 100644
--- a/bacnet-stack/ports/at91sam7s/dlmstp.c
+++ b/bacnet-stack/ports/at91sam7s/dlmstp.c
@@ -51,15 +51,15 @@ void dlmstp_copy_bacnet_address(BACNET_ADDRESS * dest, BACNET_ADDRESS * src)
 {
     int i = 0;
 
-    if (src && dest) {
-        src->mac_len = dest->mac_len;
+    if (dest && src) {
+        dest->mac_len = src->mac_len;
         for (i = 0; i < MAX_MAC_LEN; i++) {
-            src->mac[i] = dest->mac[i];
+            dest->mac[i] = src->mac[i];
         }
-        src->net = dest->net;
-        src->len = dest->len;
+        dest->net = src->net;
+        dest->len = src->len;
         for (i = 0; i < MAX_MAC_LEN; i++) {
-            src->adr[i] = dest->adr[i];
+            dest->adr[i] = src->adr[i];
         }
     }
 }
@@ -77,8 +77,8 @@ bool dlmstp_init(char *ifname)
     MSTP_Port.InputBufferSize = sizeof(RxBuffer);
     MSTP_Port.OutputBuffer = &TxBuffer[0];
     MSTP_Port.OutputBufferSize = sizeof(TxBuffer);
-    MSTP_Init.SilenceTimer = Timer_Silence;
-    MSTP_Init.SilenceTimerReset = Timer_Silence_Reset;
+    MSTP_Port.SilenceTimer = Timer_Silence;
+    MSTP_Port.SilenceTimerReset = Timer_Silence_Reset;
     MSTP_Init(&MSTP_Port);
 
     return true;
@@ -248,6 +248,7 @@ uint16_t MSTP_Get_Send(
             destination, src,
             &Transmit_Packet.pdu[0],
             Transmit_Packet.pdu_len);
+        Transmit_Packet.ready = false;
     }
 
     return pdu_len;
diff --git a/bacnet-stack/ports/at91sam7s/rs485.c b/bacnet-stack/ports/at91sam7s/rs485.c
index 9574621f..82f4fd19 100644
--- a/bacnet-stack/ports/at91sam7s/rs485.c
+++ b/bacnet-stack/ports/at91sam7s/rs485.c
@@ -163,7 +163,7 @@ void RS485_Send_Frame(
         if (!turnaround_time) {
             turnaround_time = 1;
         }
-        while (mstp_port->SilenceTimer < turnaround_time) {
+        while (mstp_port->SilenceTimer() < turnaround_time) {
             /* do nothing - wait for timer to increment */
         };
     }
@@ -180,7 +180,7 @@ void RS485_Send_Frame(
         nbytes--;
         /* per MSTP spec */
         if (mstp_port) {
-            mstp_port->SilenceTimer = 0;
+            mstp_port->SilenceTimerReset();
         }
     }
     while (!(RS485_Interface->US_CSR & AT91C_US_TXRDY)) {
@@ -195,6 +195,7 @@ void RS485_Check_UART_Data(struct mstp_port_struct_t *mstp_port)
 {
     volatile AT91PS_PIO pPIO = AT91C_BASE_PIOA;
 
+    /* FIXME: Framing or overrun error? */
     if (mstp_port->ReceiveError == true) {
         /* wait for state machine to clear this */
     }
diff --git a/bacnet-stack/ports/at91sam7s/timer.c b/bacnet-stack/ports/at91sam7s/timer.c
index b332d3dc..6a49fc20 100644
--- a/bacnet-stack/ports/at91sam7s/timer.c
+++ b/bacnet-stack/ports/at91sam7s/timer.c
@@ -330,8 +330,8 @@ void Timer_Silence_Reset(void)
 //    Moved timer startup code from main
 //    modified the peripheral clock init
 //  *****************************************************************************
-void TimerInit(void) {
-    pTimer_MSTP_Silence = dlmstp_millisecond_timer_address();
+void TimerInit(void) 
+{
     // enable the Timer0 peripheral clock
     volatile AT91PS_PMC pPMC = AT91C_BASE_PMC;
     pPMC->PMC_PCER = pPMC->PMC_PCSR | (1<<AT91C_ID_TC0);