diff --git a/src/CLIParser.cpp b/src/CLIParser.cpp
index fa2ddea..4e0afa5 100644
--- a/src/CLIParser.cpp
+++ b/src/CLIParser.cpp
@@ -82,7 +82,7 @@ void CLIParser::build() {
                     "enable gdb server and specify port to use")
             ("backend", po::value<std::string>()->default_value("interp"),
                     "the ISS backend to use, options are: interp, tcc")
-            ("isa", po::value<std::string>()->default_value("rv32imac"),
+            ("isa", po::value<std::string>()->default_value("rv32imac_m"),
                     "core or isa name to use for simulation, use '?' to get list")
             ("dump-ir",
                     "dump the intermediate representation")