diff --git a/liteeth/core/arp.py b/liteeth/core/arp.py
index e1fd892..7e95a51 100644
--- a/liteeth/core/arp.py
+++ b/liteeth/core/arp.py
@@ -53,9 +53,7 @@ class LiteEthARPTX(LiteXModule):
         self.comb += [
             packetizer.sink.last.eq(counter == (packet_words - 1)),
             If(packetizer.sink.last,
-                packetizer.sink.last_be.eq(1 if len(packetizer.sink.last_be) == 1 else
-                                           2**(packet_length % (dw // 8) - 1)
-                ),
+                packetizer.sink.last_be.eq(max(1, 2**(packet_length % (dw // 8) - 1))),
             ),
             packetizer.sink.hwtype.eq(arp_hwtype_ethernet),
             packetizer.sink.proto.eq(arp_proto_ip),