我猜recorder是这样的：

来源: 于 2015-01-18 14:38:16 [博客] [旧帖] [给我悄悄话] 本文已被阅读：次

will record and temporarily store last 30 sec of data. If no accident to trigger, it will wash the data out and keep recording. User may not be able to retrieve data. Once accident occurred, 30 sec data before and after will be stored in a permanent location for users to retrieve.