diff --git a/iflytop_canbus_protocol.hpp b/iflytop_canbus_protocol.hpp
index 668c196..4b66b09 100644
--- a/iflytop_canbus_protocol.hpp
+++ b/iflytop_canbus_protocol.hpp
@@ -290,8 +290,8 @@ typedef struct {
 } ask_taskinfo_t;
 
 typedef struct {
-  uint16_t total_heap_size;
-  uint16_t free_heap_size;
+  uint32_t total_heap_size;
+  uint32_t free_heap_size;
   uint16_t taskNum;
   uint16_t sysHasRun;
 } ack_sysinfo_t;