Research On Data Transmit Interface Of Portable Oscilloscope

Digital storage oscilloscope, as a general detection tool of waveform signal,is widely used by most researchers and engineers. But traditional oscilloscopenot only has a huge size that seems a little heavy, but also is used just inlaboratory. It’s not so convenient to use it outdoors or in the scene of file testing.Also most of oscilloscope adopts traditional push-button operation, not to say tohave a nice User Interface display. Connecting the internet is practical lyimpossible to traditional oscilloscope. So it’s meaningful to develop a kind ofoscilloscope that could be easy to operate and portable. Such oscilloscope has alot of advantages, such as supporting Multi-touch function, displaying colorfully,also user interface friendly.The aim of this project is to design a kind of portable digital oscilloscopethan owns Android operating system. It uses the architecture of FPGA and ARM.FPGA is responsible for the control of oscilloscope front-end collecting system.Also it controls the trigger and data caching. ARM, as the processor, implementsdata acquisition circuit for subsequent data processing and analysis. Also it isresponsible human computer interaction and panels operation. Between thefront-end data acquisition module and back-end data processing module is SDbus transmitting protocol interface. Waveform data from front-end acquisitionmodule convey to back-end oscilloscope software application through thisinterface. This paper introduce how to design that transmit interface.This paper is focused on the SD bus transmit protocol fundamental theoryand timing sequence. Using FPGA to simulate a virtual SD Card is to as theoscilloscope data transmit channel. Divide small module according to thefunction and then design each sub-module with the VHDL hardware descriptionlanguage. After debugging and verifying to the system logic circuit, OscilloscopeARM host can recognized the FPGA to a SD Card and read its Waveform data.