Research And Application Of Digital Oscilloscope Based On MQX RTOS

At the present day, the digital oscilloscope has been an indispensable electronicmeasuring instrument. However, it hasn’t been widely used as a teaching instrument inclass for two reasons. Firstly, its market price is relatively high. Secondly, thecomplicated function of digital oscilloscope is not in great need for daily teaching. MQXis an embedded real-time operating system promoted by Freescale Semiconductor in2009. Meanwhile, it is also the key research project for Freescale Embedded ResearchCenter of Soochow University, which is authorized by Freescale Semiconductor. In2013,our center proposed the application framework of SD-MQX, and applied MQX to aself-built hardware platform. In this context, this thesis made a preliminary exploration ofMQX usage and designed a MQX-K60simple digital oscilloscope which on one handcould take samples and store samples independently, and on the other hand, couldconnect with a PC and act as a virtual instrument. Balancing the cost and performancerequirements, this project chosed the Kinetis K60N512chip produced by Freescale as thecontrolling unit and did the following research.(1)Bearing the idea of embedded hardware components in mind, this projectdesigned the hardware component module of oscilloscope, including SD-DSO_COREand SD-DSO_CTL. The SD-DSO_CORE integrated the basic function module like AD,USB, Flash, etc.; SD-DSO_CTL consisted of peripheral control circuit and controllingresult display circuit.(2)Used the multitasking processing capacity of real-time operating system toimplement the two independent operating mode of the oscilloscope; based on the idea ofMQX driver classification, this project classified the oscilloscope underlying driver intotwo device drivers with independent function which can be used flexibly for the twooperating modes, designed an independent oscilloscope working mode; taken intoaccount the communicative need between oscilloscope and personal computer, this thesismainly focuses on the complex driver USB of MQX by investigating into the fourth layer architecture, made a USB communication solution which is suitable for oscilloscope’stransmission and gave a separate module test for USB driver.(3)With regard to the characteristics of the K60N512, wrote PC’s software for theoscilloscope, strengthened the oscilloscope’s internal temperature measurement function;achieved the connection between the oscilloscope’s high-end software and the underlyingsoftware through the command control, and implemented the two independent workingmodes of the oscilloscope.Via the practical application test mentioned in this article, the MQX-K60simpledigital oscilloscope designed in this project has been proved to be of certain practicalvalue. At the same time, this project made a preliminary exploration of MQX’sapplicantion. In the process of development, encapsulating complex driver USB into acomponent with independent function provides basis for the subsequent MQX researches.