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dm365 usb sd卡



大家好,请教下,dm365的usb当做devices,连接PC机时,怎么实现DM365原本所接的SD卡

数据被PC机直接读取?

就好像我们现在使用的手机都支持的,USB接PC机,直接拷贝手机里的SD卡数据。

什么原理?主要是软件上还是硬件处理?

  • 主要是软件的工作。基本原理是:数据从MMC/SD模块,经DM365内部总线到缓存,数据再从缓存经DM365内部总线到USB模块,期间还可以使用DMA。

  • 谢谢!那就是这主要都是驱动层的工作吧,TI的SDK里有相关的驱动代码吗?

  • 你好,

    这个问题我查了一下,比较麻烦,你说的要DM365作为device从设备和PC机的HOST通信,不能直接实现,因为dm365的usb仅限于host模式,不能作为从设备。因此dm365做这个设计,不太合适。因此SDK里提供的USB 驱动,仅限于USB slave从设备与DM365的USB host接口连接。希望这些能给你提供一些帮助。

  • 谢谢!我还是有点疑问。我看DM365芯片资料里面写着

    USB Port with Integrated 2.0 High-Speed PHY 
    that Supports
    – USB 2.0 High-Speed Device
    – USB 2.0 High-Speed Host (mini-host, 
    supporting one external device)
    – USB On The Go (HS-USB OTG)

    它不是支持OTG吗,那它不就是可以当USB slave从设备与PCUSB host接口连接吗?

    在TMS320DM36x DMSoC Universal Serial Bus User's Guide.pdf这份文档里具体写到

    3 USB Controller Host and Peripheral Modes Operation

    The USB controller can be used in a range of different environments. It can be used as either a
    high-speed or a full-speed USB peripheral device attached to a conventional USB host (such as a PC). It
    can be used as either host or peripheral device in point-to-point data transfers with another peripheral
    device - or, if the other device also contains a Dual-Role Controller, the two devices can switch roles as
    required. (This second device may be either a high-speed, full-speed or low-speed USB function.) Or the
    controller can be used as the host to a range of such peripheral devices in a multi-point setup.