diff --git a/assembler/assembler.py b/assembler/assembler.py
index f4dbbe6..4d36209 100644
--- a/assembler/assembler.py
+++ b/assembler/assembler.py
@@ -175,7 +175,7 @@ class Assembler(object):
 		for argument in self._commands_by_mnemonic[cmd]["args"][1:]:
 			should_be_comma = next(self._tokenizer)
 			if(should_be_comma != ","):
-				self.raise_unexpected_token(cmd, should_be_whitespace)
+				self.raise_unexpected_token(cmd, "','", should_be_comma)
 
 			self._word_count += 1
 			self._code_objects.append(