diff -r 680ea4684209 -r 0b636dc947a2 modbus/modbus.py
--- a/modbus/modbus.py	Mon Dec 21 21:15:47 2020 +0000
+++ b/modbus/modbus.py	Mon Dec 21 22:26:36 2020 +0000
@@ -140,14 +140,23 @@
             "description": "Modbus request execution control flag",
             "children": []})        
         entries.append({
-            "name": "Request Status flag",
+            "name": "Modbus Request Status flag",
             "type": LOCATION_VAR_MEMORY,
-            "size": 16,          # WORD flag
-            "IEC_type": "WORD",  # WORD flag
+            "size": 8,           # BYTE flag
+            "IEC_type": "BYTE",  # BYTE flag
             "var_name": "var_name",
-            "location": "W" + ".".join([str(i) for i in current_location]) + ".0.1",
+            "location": "B" + ".".join([str(i) for i in current_location]) + ".0.1",
             "description": "Modbus request status flag",
             "children": []})        
+        entries.append({
+            "name": "Modbus Error Code",
+            "type": LOCATION_VAR_MEMORY,
+            "size": 8,           # BYTE flag
+            "IEC_type": "BYTE",  # BYTE flag
+            "var_name": "var_name",
+            "location": "B" + ".".join([str(i) for i in current_location]) + ".0.2",
+            "description": "Modbus Error Code received in Modbus error frame",
+            "children": []})        
         for offset in range(address, address + count):
             entries.append({
                 "name": dataname + " " + str(offset),
@@ -897,9 +906,13 @@
                                 if iecvar["LOC"][4] == 0:
                                     loc_vars.append("u16 *" + str(iecvar["NAME"]) + " = &client_requests[%d].flag_exec_req;" % (client_requestid))
                                     loc_vars_list.append(str(iecvar["NAME"]))
-                                # Add if it is a Communication Status Flag (mapped onto %QWa.b.c.0.1), so last number is a '1'
+                                # Add if it is a "Modbus Request Status flag" (mapped onto %QWa.b.c.0.1), so last number is a '1'
                                 if iecvar["LOC"][4] == 1:
-                                    loc_vars.append("u16 *" + str(iecvar["NAME"]) + " = &client_requests[%d].flag_exec_status;" % (client_requestid))
+                                    loc_vars.append("u8 *" + str(iecvar["NAME"]) + " = &client_requests[%d].flag_tn_error_code;" % (client_requestid))
+                                    loc_vars_list.append(str(iecvar["NAME"]))
+                                # Add if it is a "Modbus Error code" (mapped onto %QWa.b.c.0.2), so last number is a '2'
+                                if iecvar["LOC"][4] == 2:
+                                    loc_vars.append("u8 *" + str(iecvar["NAME"]) + " = &client_requests[%d].flag_mb_error_code;" % (client_requestid))
                                     loc_vars_list.append(str(iecvar["NAME"]))
                     client_requestid += 1
                 tcpclient_node_count += 1
@@ -947,9 +960,13 @@
                                 if iecvar["LOC"][4] == 0:
                                     loc_vars.append("u16 *" + str(iecvar["NAME"]) + " = &client_requests[%d].flag_exec_req;" % (client_requestid))
                                     loc_vars_list.append(str(iecvar["NAME"]))
-                                # Add if it is a Communication Status Flag (mapped onto %QWa.b.c.0.1), so last number is a '1'
+                                # Add if it is a "Modbus Request Status flag" (mapped onto %QWa.b.c.0.1), so last number is a '1'
                                 if iecvar["LOC"][4] == 1:
-                                    loc_vars.append("u16 *" + str(iecvar["NAME"]) + " = &client_requests[%d].flag_exec_status;" % (client_requestid))
+                                    loc_vars.append("u8 *" + str(iecvar["NAME"]) + " = &client_requests[%d].flag_tn_error_code;" % (client_requestid))
+                                    loc_vars_list.append(str(iecvar["NAME"]))
+                                # Add if it is a "Modbus Error code" (mapped onto %QWa.b.c.0.2), so last number is a '2'
+                                if iecvar["LOC"][4] == 2:
+                                    loc_vars.append("u8 *" + str(iecvar["NAME"]) + " = &client_requests[%d].flag_mb_error_code;" % (client_requestid))
                                     loc_vars_list.append(str(iecvar["NAME"]))
                     client_requestid += 1
                 rtuclient_node_count += 1