The Development And Application Of USB Function In The Handheld Digital Storage

The handheld digital storage oscilloscope is widely used in field maintenance, installation and operation monitoring and so on in industrial and electronic field. In order to facilitate communication with the computer and the peripheral equipment, the communication interface of handheld digital storage oscilloscope is a key link to extern its function.Based on the USB OTG technology, the realization of the interface communication on handheld oscilloscope has gradually become a hot spot of the oscilloscope interface applications.Traditional oscilloscope adopting micro controller to control the special chip USB realizes USB interface communication, additional USB chip will increase the volume of oscilloscope, In the design of the DSO system, select microcontroller STM32F107VC which integrated USB OTG controller to realize the USB OTG interface communication, simplified the hardware structure of handheld digital storage oscilloscope, stand out the portable characteristic of handheld oscilloscope. At the same time, The ST company also offers firmware library of the series of STM chip, improve the efficiency of software development in DSO system. Combined with the chip of STM32F107VC, making for handheld oscilloscope more practical, easier to operate, chose μ C/OS-II operating system and embedded μC/GUI. The technology proposal that applied STM32F107VC+μ C/OS-II+μ C/GUI in this paper mainly make a further study to realize the function of handheld USB OTG oscilloscope interface communication and man-machine interaction.The realization of USB host interface communication in DSO system is the key point and the difficulty in this paper. In order to achieve the goal--he communication between oscilloscope and USB flash disk, design OTG function module and display module on hardware platform, study the enumeration of USB flash disk, the design of mass storage device driver and the load of file system in software. Development of host package provides a reference for embedded USB host's development and transplant. At the same time, design the Device equipment firmware program and develop Device package from USB Device interface communication in the DSO system. In order to verify the realization of USB OTG interface communication in DSO system, developing the interface and menu of the DSO system and drawing the waveform curves. And then, debug the hardware and software of Host module, Device module based on the USB OTG function and display module in DSO system, then reach the experimental result.The experimental results:when DSO is host, it realizes the waveform curves and interface transmission between the USB flash disk and oscilloscope; when it is Device, the PC can identify DSO equipment. In the USB OTG interface, it can realize the Host function and Device function of the handheld digital storage oscilloscope, achieve the purpose of the digital storage oscilloscope's miniaturization and multi function.