diff --git a/TC1/http_server/app_httpd.c b/TC1/http_server/app_httpd.c
index c8dc116..0b8abbd 100644
--- a/TC1/http_server/app_httpd.c
+++ b/TC1/http_server/app_httpd.c
@@ -55,6 +55,7 @@ const struct httpd_wsgi_call g_app_handlers[];
 char power_info_json[2560] = {0};
 char up_time[16] = "00:00:00";
 #define CHUNK_SIZE 512  // 每次发送 512 字节，避免 buffer 太大
+#define OTA_BUFFER_SIZE 512
 
 /*
 void GetPraFromUrl(char* url, char* pra, char* val)