diff --git a/cactuscore/uhal/tools/scripts/gen_ipbus_addr_decode b/cactuscore/uhal/tools/scripts/gen_ipbus_addr_decode
index f396ff0ac..3db485e9a 100755
--- a/cactuscore/uhal/tools/scripts/gen_ipbus_addr_decode
+++ b/cactuscore/uhal/tools/scripts/gen_ipbus_addr_decode
@@ -123,8 +123,13 @@ class nodetree(object):
             s = s + prefix + i.name + " " + hex(i.ref.getAddress()) + " " + hex(i.width) + " " + str(i.flag) + "\n"
             if i.desc: s = s + self.dump(i, prefix + "  ")
         return s
-    
+
     def assign_width(self, n):
+        errors = []
+        self._assign_width(n, errors)
+        return len(errors) == 0
+
+    def _assign_width(self, n, errors_detected):
         n.sort()
         if n.ref is not None:
             addr = n.ref.getAddress()
@@ -142,11 +147,14 @@ class nodetree(object):
                 saddr = i.ref.getAddress()
                 if saddr < max_addr:
                     log.error("Overlap between nodes detected: " + i.name + " " + hex(saddr) + " "+ hex(max_addr))
-                max_addr = saddr + pow(2, self.assign_width(i))
-                if max_addr > top_addr: top_addr = max_addr
+                    errors_detected.append(i.name)
+                max_addr = saddr + pow(2, self._assign_width(i, errors_detected))
+                if max_addr > top_addr:
+                    top_addr = max_addr
             n.width = int(math.ceil(math.log(top_addr - addr,2)))
         if addr % pow(2, n.width) != 0:
-            log.error("Non-aligned base address detected: " + n.name + " " + hex(addr) + " " + hex(n.width))
+            log.error("Node '" + n.name + "' at " + hex(addr) + ": Width, " + hex(n.width) + ", produces address mask " + hex(pow(2,n.width)) + " that is not aligned with node's base address")
+            errors_detected.append(n.name)
         return n.width
 
     def get_nodes(self, n):
@@ -160,6 +168,9 @@ class nodetree(object):
 
 #===========================================================================================
 
+EXIT_CODE_INCORRECT_ARGUMENTS = 1
+EXIT_CODE_ARG_PARSING_ERROR   = 2
+EXIT_CODE_NODE_ADDRESS_ERRORS = 3
 
 def main():    
 
@@ -180,7 +191,7 @@ def main():
         opts, args = getopt.getopt(sys.argv[1:], "vdnht:", ["verbose","debug","dry-run","help","template="])
     except getopt.GetoptError, err:
         log.critical(__doc__)
-        sys.exit(2)
+        sys.exit(EXIT_CODE_ARG_PARSING_ERROR)
     for o, a in opts:
         if o in ("-v", "--verbose"):
             log.setLevel(logging.INFO)
@@ -199,7 +210,7 @@ def main():
     # make sure that exactly one argument was given, later assumed to be the xml file name
     if len(args) != 1:
         log.critical("Incorrect usage - invalid number of arguments! Make sure that options come before argument.\n" + __doc__)
-        sys.exit(1)
+        sys.exit(EXIT_CODE_INCORRECT_ARGUMENTS)
 
     try:
         device = uhal.getDevice("dummy","ipbusudp-1.3://localhost:12345","file://" + args[0])
@@ -212,7 +223,11 @@ def main():
         f = d.getFirmwareInfo()
         p = "type" in f and f["type"] == "endpoint"
         t.add(node(i,d,p))
-    t.assign_width(t.root)
+    node_address_errors_detected = False
+    if not t.assign_width(t.root):
+        log.error("Node errors detected (e.g. non-aligned addresses, or address overlaps); exiting early before writing output")
+        sys.exit(EXIT_CODE_NODE_ADDRESS_ERRORS)
+
     uhal_slaves = t.get_nodes(t.root)
     moduleName = os.path.splitext(os.path.basename(args[0]))[0]