diff --git a/nemu/src/device/io/map.c b/nemu/src/device/io/map.c
index d610558..045d6ac 100644
--- a/nemu/src/device/io/map.c
+++ b/nemu/src/device/io/map.c
@@ -57,8 +57,8 @@ word_t map_read(paddr_t addr, int len, IOMap *map) {
   check_bound(map, addr);
   paddr_t offset = addr - map->low;
   invoke_callback(map->callback, offset, len, false); // prepare data to read
-//  word_t ret = host_read(map->space + offset, len);
-word_t ret = *(word_t*)(map->space + offset);
+  word_t ret = host_read(map->space + offset, len);
+//word_t ret = *(word_t*)(map->space + offset);
 printf("map_read: %p, %d\n", map->space + offset, ret);
   return ret;
 }