update

app/main.c

@@ -23,15 +23,16 @@ int serial_test() {
   }
 }
 int main(int argc, char *argv[]) {
+  /* 参数判断 */
   if (argc != 2) {
     printf("please input com id\n");
     return -1;
   }
   printf("Serial port number is:%s\n", argv[1]);
 
+  /* 字符串转int类型 */
   serial_com_id = atoi(argv[1]);
-
-  if (serial_com_id == 0) {
+  if (serial_com_id == 0) {/*  */
     /* 转换错误 */
     printf("The serial port id is incorrect\n");
     return -2;