来电铃声随机换

将要随机更换的铃声复制到应用创建的目录(rst)下，当有电话接入时，就会即随机替换来电铃声。支持开机自启动。运行只消耗5M内存。
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使用方法：
把想要更换的铃声复制到自动创建的内存的rst目录下即可。 We will replace the random ringing copied into the directory created by the application (rst) next, when a telephone call, it will replace the ringing tone that is random. Support boot from the start. 5M run only consume memory.
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Instructions:
The copy you want to replace the ring to the next memory can be automatically created rst directory.