diff --git a/test/isup_codec_tests.erl b/test/isup_codec_tests.erl
new file mode 100644
index 0000000..8d44f31
--- /dev/null
+++ b/test/isup_codec_tests.erl
@@ -0,0 +1,16 @@
+-module(isup_codec_tests).
+-author('Harald Welte <laforge@gnumonks.org>').
+
+-include_lib("eunit/include/eunit.hrl").
+
+-include("isup.hrl").
+
+
+-define(ISUP_GRS_BIN, <<1,0,23,1,1,14>>).
+-define(ISUP_GRS_DEC, #isup_msg{msg_type = 23,cic = 1, parameters = [{22,{1,<<14>>}}]}).
+
+grs_dec_test() ->
+	?assertEqual(?ISUP_GRS_DEC, isup_codec:parse_isup_msg(?ISUP_GRS_BIN)).
+grs_enc_test() ->
+	?assertEqual(?ISUP_GRS_BIN, isup_codec:encode_isup_msg(?ISUP_GRS_DEC)).
+