diff --git a/nemu/include/common.h b/nemu/include/common.h
index fbffaa5..3197dd6 100644
--- a/nemu/include/common.h
+++ b/nemu/include/common.h
@@ -23,6 +23,7 @@
 
 #include <generated/autoconf.h>
 #include <macro.h>
+#include <types.h>
 
 #ifdef CONFIG_TARGET_AM
 #include <klib.h>
@@ -31,23 +32,6 @@
 #include <stdlib.h>
 #endif
 
-#if CONFIG_MBASE + CONFIG_MSIZE > 0x100000000ul
-#define PMEM64 1
-#endif
-
-typedef MUXDEF(CONFIG_ISA64, uint64_t, uint32_t) word_t;
-typedef MUXDEF(CONFIG_ISA64, int64_t, int32_t)  sword_t;
-static const word_t WORD_T_MAX = MUXDEF(CONFIG_ISA64, UINT64_MAX, UINT32_MAX);
-static const sword_t SWORD_T_MAX = MUXDEF(CONFIG_ISA64, INT64_MAX, INT32_MAX);
-static const sword_t SWORD_T_MIN = MUXDEF(CONFIG_ISA64, INT64_MIN, INT32_MIN);
-#define WORD_BYTES MUXDEF(CONFIG_ISA64, 8, 4)
-#define FMT_WORD MUXDEF(CONFIG_ISA64, "0x%016" PRIx64, "0x%08" PRIx32)
-
-typedef word_t vaddr_t;
-typedef MUXDEF(PMEM64, uint64_t, uint32_t) paddr_t;
-#define FMT_PADDR MUXDEF(PMEM64, "0x%016" PRIx64, "0x%08" PRIx32)
-typedef uint16_t ioaddr_t;
-
 #include <debug.h>
 
 #endif
diff --git a/nemu/include/types.h b/nemu/include/types.h
new file mode 100644
index 0000000..d034049
--- /dev/null
+++ b/nemu/include/types.h
@@ -0,0 +1,19 @@
+#ifndef __TYPES_H__
+#define __TYPES_H__
+#if CONFIG_MBASE + CONFIG_MSIZE > 0x100000000ul
+#define PMEM64 1
+#endif
+
+typedef MUXDEF(CONFIG_ISA64, uint64_t, uint32_t) word_t;
+typedef MUXDEF(CONFIG_ISA64, int64_t, int32_t)  sword_t;
+static const word_t WORD_T_MAX = MUXDEF(CONFIG_ISA64, UINT64_MAX, UINT32_MAX);
+static const sword_t SWORD_T_MAX = MUXDEF(CONFIG_ISA64, INT64_MAX, INT32_MAX);
+static const sword_t SWORD_T_MIN = MUXDEF(CONFIG_ISA64, INT64_MIN, INT32_MIN);
+#define WORD_BYTES MUXDEF(CONFIG_ISA64, 8, 4)
+#define FMT_WORD MUXDEF(CONFIG_ISA64, "0x%016" PRIx64, "0x%08" PRIx32)
+
+typedef word_t vaddr_t;
+typedef MUXDEF(PMEM64, uint64_t, uint32_t) paddr_t;
+#define FMT_PADDR MUXDEF(PMEM64, "0x%016" PRIx64, "0x%08" PRIx32)
+typedef uint16_t ioaddr_t;
+#endif
\ No newline at end of file