diff --git a/bacnet-stack/ports/at91sam7s/dlmstp.c b/bacnet-stack/ports/at91sam7s/dlmstp.c
index 53dc164d..1794f1de 100644
--- a/bacnet-stack/ports/at91sam7s/dlmstp.c
+++ b/bacnet-stack/ports/at91sam7s/dlmstp.c
@@ -290,14 +290,6 @@ static bool dlmstp_compare_data_expecting_reply(
        confirmed, simple ack, abort, reject, error */
     reply.pdu_type = reply_pdu[offset] & 0xF0;
     switch (reply.pdu_type) {
-        case PDU_TYPE_CONFIRMED_SERVICE_REQUEST:
-            reply.invoke_id = reply_pdu[offset + 2];
-            /* segmented message? */
-            if (reply_pdu[offset] & BIT3)
-                reply.service_choice = reply_pdu[offset + 5];
-            else
-                reply.service_choice = reply_pdu[offset + 3];
-            break;
         case PDU_TYPE_SIMPLE_ACK:
             reply.invoke_id = reply_pdu[offset + 1];
             reply.service_choice = reply_pdu[offset + 2];
diff --git a/bacnet-stack/ports/bdk-atxx4-mstp/dlmstp.c b/bacnet-stack/ports/bdk-atxx4-mstp/dlmstp.c
index d9cf3dee..bb4b9d4a 100644
--- a/bacnet-stack/ports/bdk-atxx4-mstp/dlmstp.c
+++ b/bacnet-stack/ports/bdk-atxx4-mstp/dlmstp.c
@@ -289,14 +289,6 @@ static bool dlmstp_compare_data_expecting_reply(
        confirmed, simple ack, abort, reject, error */
     reply.pdu_type = reply_pdu[offset] & 0xF0;
     switch (reply.pdu_type) {
-        case PDU_TYPE_CONFIRMED_SERVICE_REQUEST:
-            reply.invoke_id = reply_pdu[offset + 2];
-            /* segmented message? */
-            if (reply_pdu[offset] & BIT3)
-                reply.service_choice = reply_pdu[offset + 5];
-            else
-                reply.service_choice = reply_pdu[offset + 3];
-            break;
         case PDU_TYPE_SIMPLE_ACK:
             reply.invoke_id = reply_pdu[offset + 1];
             reply.service_choice = reply_pdu[offset + 2];
diff --git a/bacnet-stack/ports/dos/dlmstp.c b/bacnet-stack/ports/dos/dlmstp.c
index 31c6ad65..5337fba9 100644
--- a/bacnet-stack/ports/dos/dlmstp.c
+++ b/bacnet-stack/ports/dos/dlmstp.c
@@ -331,14 +331,6 @@ static bool dlmstp_compare_data_expecting_reply(
        confirmed, simple ack, abort, reject, error */
     reply.pdu_type = reply_pdu[offset] & 0xF0;
     switch (reply.pdu_type) {
-        case PDU_TYPE_CONFIRMED_SERVICE_REQUEST:
-            reply.invoke_id = reply_pdu[offset + 2];
-            /* segmented message? */
-            if (reply_pdu[offset] & BIT3)
-                reply.service_choice = reply_pdu[offset + 5];
-            else
-                reply.service_choice = reply_pdu[offset + 3];
-            break;
         case PDU_TYPE_SIMPLE_ACK:
             reply.invoke_id = reply_pdu[offset + 1];
             reply.service_choice = reply_pdu[offset + 2];
diff --git a/bacnet-stack/ports/linux/dlmstp.c b/bacnet-stack/ports/linux/dlmstp.c
index de89b072..a4ef36b5 100644
--- a/bacnet-stack/ports/linux/dlmstp.c
+++ b/bacnet-stack/ports/linux/dlmstp.c
@@ -415,15 +415,6 @@ static bool dlmstp_compare_data_expecting_reply(
        confirmed, simple ack, abort, reject, error */
     reply.pdu_type = reply_pdu[offset] & 0xF0;
     switch (reply.pdu_type) {
-        case PDU_TYPE_CONFIRMED_SERVICE_REQUEST:
-            reply.invoke_id = reply_pdu[offset + 2];
-            /* segmented message? */
-            if (reply_pdu[offset] & BIT3) {
-                reply.service_choice = reply_pdu[offset + 5];
-            } else {
-                reply.service_choice = reply_pdu[offset + 3];
-            }
-            break;
         case PDU_TYPE_SIMPLE_ACK:
             reply.invoke_id = reply_pdu[offset + 1];
             reply.service_choice = reply_pdu[offset + 2];
diff --git a/bacnet-stack/ports/linux/dlmstp_linux.c b/bacnet-stack/ports/linux/dlmstp_linux.c
index d9583418..a2ccca6e 100644
--- a/bacnet-stack/ports/linux/dlmstp_linux.c
+++ b/bacnet-stack/ports/linux/dlmstp_linux.c
@@ -465,15 +465,6 @@ bool dlmstp_compare_data_expecting_reply(
        confirmed, simple ack, abort, reject, error */
     reply.pdu_type = reply_pdu[offset] & 0xF0;
     switch (reply.pdu_type) {
-        case PDU_TYPE_CONFIRMED_SERVICE_REQUEST:
-            reply.invoke_id = reply_pdu[offset + 2];
-            /* segmented message? */
-            if (reply_pdu[offset] & BIT3) {
-                reply.service_choice = reply_pdu[offset + 5];
-            } else {
-                reply.service_choice = reply_pdu[offset + 3];
-            }
-            break;
         case PDU_TYPE_SIMPLE_ACK:
             reply.invoke_id = reply_pdu[offset + 1];
             reply.service_choice = reply_pdu[offset + 2];
diff --git a/bacnet-stack/ports/pic18f6720/mstp.c b/bacnet-stack/ports/pic18f6720/mstp.c
index c36b9d1a..0d353349 100644
--- a/bacnet-stack/ports/pic18f6720/mstp.c
+++ b/bacnet-stack/ports/pic18f6720/mstp.c
@@ -606,14 +606,6 @@ static bool mstp_compare_data_expecting_reply(
        confirmed, simple ack, abort, reject, error */
     reply.pdu_type = reply_pdu[offset] & 0xF0;
     switch (reply.pdu_type) {
-        case PDU_TYPE_CONFIRMED_SERVICE_REQUEST:
-            reply.invoke_id = reply_pdu[offset + 2];
-            /* segmented message? */
-            if (reply_pdu[offset] & BIT3)
-                reply.service_choice = reply_pdu[offset + 5];
-            else
-                reply.service_choice = reply_pdu[offset + 3];
-            break;
         case PDU_TYPE_SIMPLE_ACK:
             reply.invoke_id = reply_pdu[offset + 1];
             reply.service_choice = reply_pdu[offset + 2];
diff --git a/bacnet-stack/ports/stm32f10x/dlmstp.c b/bacnet-stack/ports/stm32f10x/dlmstp.c
index cb9bb598..9cc74484 100644
--- a/bacnet-stack/ports/stm32f10x/dlmstp.c
+++ b/bacnet-stack/ports/stm32f10x/dlmstp.c
@@ -293,14 +293,6 @@ static bool dlmstp_compare_data_expecting_reply(
        confirmed, simple ack, abort, reject, error */
     reply.pdu_type = reply_pdu[offset] & 0xF0;
     switch (reply.pdu_type) {
-        case PDU_TYPE_CONFIRMED_SERVICE_REQUEST:
-            reply.invoke_id = reply_pdu[offset + 2];
-            /* segmented message? */
-            if (reply_pdu[offset] & BIT3)
-                reply.service_choice = reply_pdu[offset + 5];
-            else
-                reply.service_choice = reply_pdu[offset + 3];
-            break;
         case PDU_TYPE_SIMPLE_ACK:
             reply.invoke_id = reply_pdu[offset + 1];
             reply.service_choice = reply_pdu[offset + 2];
diff --git a/bacnet-stack/ports/win32/dlmstp-mm.c b/bacnet-stack/ports/win32/dlmstp-mm.c
index de3fc453..6acea9e1 100644
--- a/bacnet-stack/ports/win32/dlmstp-mm.c
+++ b/bacnet-stack/ports/win32/dlmstp-mm.c
@@ -365,14 +365,6 @@ bool dlmstp_compare_data_expecting_reply(
        confirmed, simple ack, abort, reject, error */
     reply.pdu_type = reply_pdu[offset] & 0xF0;
     switch (reply.pdu_type) {
-        case PDU_TYPE_CONFIRMED_SERVICE_REQUEST:
-            reply.invoke_id = reply_pdu[offset + 2];
-            /* segmented message? */
-            if (reply_pdu[offset] & BIT3)
-                reply.service_choice = reply_pdu[offset + 5];
-            else
-                reply.service_choice = reply_pdu[offset + 3];
-            break;
         case PDU_TYPE_SIMPLE_ACK:
             reply.invoke_id = reply_pdu[offset + 1];
             reply.service_choice = reply_pdu[offset + 2];
diff --git a/bacnet-stack/ports/win32/dlmstp.c b/bacnet-stack/ports/win32/dlmstp.c
index 1fddac76..c24ee3ba 100644
--- a/bacnet-stack/ports/win32/dlmstp.c
+++ b/bacnet-stack/ports/win32/dlmstp.c
@@ -353,14 +353,6 @@ static bool dlmstp_compare_data_expecting_reply(
        confirmed, simple ack, abort, reject, error */
     reply.pdu_type = reply_pdu[offset] & 0xF0;
     switch (reply.pdu_type) {
-        case PDU_TYPE_CONFIRMED_SERVICE_REQUEST:
-            reply.invoke_id = reply_pdu[offset + 2];
-            /* segmented message? */
-            if (reply_pdu[offset] & BIT3)
-                reply.service_choice = reply_pdu[offset + 5];
-            else
-                reply.service_choice = reply_pdu[offset + 3];
-            break;
         case PDU_TYPE_SIMPLE_ACK:
             reply.invoke_id = reply_pdu[offset + 1];
             reply.service_choice = reply_pdu[offset + 2];
diff --git a/bacnet-stack/ports/xplained/dlmstp.c b/bacnet-stack/ports/xplained/dlmstp.c
index f83ce437..894f7b92 100644
--- a/bacnet-stack/ports/xplained/dlmstp.c
+++ b/bacnet-stack/ports/xplained/dlmstp.c
@@ -269,14 +269,6 @@ static bool dlmstp_compare_data_expecting_reply(uint8_t * request_pdu,
        confirmed, simple ack, abort, reject, error */
     reply.pdu_type = reply_pdu[offset] & 0xF0;
     switch (reply.pdu_type) {
-        case PDU_TYPE_CONFIRMED_SERVICE_REQUEST:
-            reply.invoke_id = reply_pdu[offset + 2];
-            /* segmented message? */
-            if (reply_pdu[offset] & BIT(3))
-                reply.service_choice = reply_pdu[offset + 5];
-            else
-                reply.service_choice = reply_pdu[offset + 3];
-            break;
         case PDU_TYPE_SIMPLE_ACK:
             reply.invoke_id = reply_pdu[offset + 1];
             reply.service_choice = reply_pdu[offset + 2];