DTU SIM900开源最好的程序，可以参考做GPRS模块开发

新开发板\\\\学习板原理图\\\\GPRS底板.pdf

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    ........\\\\............\\\\STM32.pdf

    ........\\\\参考代码\\\\服务器接收示范(MFC完成端口模型).rar

    ........\\\\........\\\\服务器接收示范(控制台完成端口模型).rar

    ........\\\\........\\\\键盘\\\\key44.c

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    ........\\\\........\\\\....\\\\..nker\\\\ctype.al

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    ........\\\\........\\\\....\\\\......\\\\stdio.al

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    ........\\\\........\\\\....\\\\Exe\\\\key44.hex

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    ........\\\\........\\\\LED，通讯调试程序\\\\2.c

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    ........\\\\........\\\\led调试代码以及A口控制继电器  蜂鸣器\\\\2.c

    ........\\\\........\\\\....................................\\\\2.c!

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    ........\\\\........\\\\....................................\\\\..nker\\\\2.a

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    ........\\\\........\\\\....................................\\\\......\\\\bcd.al

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