Study Of Universal Test System Of Cordless Laser Mouse

The universal test system of cordless laser mouse has been studied inmy paper.It shows the design principle of mouse, why it can be test, theideas of test and the coming truth of test system. The test system have thebest design level in the world not only technically but also functionally. Optical mouse mainly consists of four parts, LED, lens, OpticalEngine, Micro Controller. The LED on the bottom of the mouse shine the surface by 30 angleand produce a shadow. The light have been refracted through another lensto sensor. Sensor get a continuous picture when mouse moving and DSP ofsensor will compare and analyze these picture to judge the movingdirection and displacement. Then the information will be sent toMCU(Micro Controller Unit) by SPI. These massage will be sent to PCafter MCU handle them. The working principle of laser mouse isbasically same as optical mouse's, just replace the normal LED to laserLED.The optical engine is the most exact component in all thecomponents of optical mouse, especially laser engine. The DPI, samplingfrequency and so on which we most care about is determined by opticalengine.All the function of mouse have been maken sure by the test systemand parameter is good, such as the veracity and speed of direction anddisplacement of moving of mouse, the picture quality made by sensor.Project SumatraLSR is taken as a sample to show how test systemworks. SumatraLSR is a cordless laser mouse. The design principlerelated to test of SumatraLSR first is expatiated, including FWS, TRDand HWS which the test system is based on.FWS will be post after FW programmed in MCU done. How all thefunctional module of mouse works will be explained in FWS, just like thepin assignment of MCU, voltage module, optical system, switch module,RF module, mouse working mode, test mode and EEPROM memory map,the last two is the base of designing test system.EE will generate TRD and HWS for TDE to set up test system. Itcontains the test item and test limits, test condition.The test system of cordless laser mouse consists of two parts.Simplon is the most important design in the test system of hardware. Aswe know, SumatraLSR is cordless laser mouse, if we want to test it,wemust connect it to PC and talk each other, just like sent command toMCU, operate the mouse module, read all kinds of parameter like current,comfiirm the function. But by who?Simplon is designed as a bridge form mouse to PC, named by a realbridge of Switzerland. Through Simplon We can sent command tomouse,enter some test mode, read/write parameter,comfirm the mousefunctional just like roller supported by FW.Second, there is another wonderful design about applying DC motorto test mouse tracking. When testing, DC motor running replace mousemoving and exactly test the tracking angle, DPI, Stand Deviation.Furthermore there are a lot of merit in the test system, like stepping motorapplied to test roller, the antenna design applied to test radio frequency,selecting ophir to measure the laser power.But the test system still need to be improved. In FT test station thereare a little more test hardware and interface, as a result, the hardware isdifficult to maintain. Cost down is another target in the future.Concerning the software of test system, Universal test system isbased on the Delphi language to create a special test platform, formatinitialing hardware and command, module the arithmetic. Therefore, itprovide the convenience to TDE, simple the process of modifying the testplan and easy to master, operate the software. But the functional modulemust be updated at any moment. SumatraLSR's laser engine is 7050Sensor of Aiglent company, which is not applied in any cordless lasermouse before, so the related functional module, namely, dll are notupdated, just like Laser.dll to setting laser power of mouse,UTS_Parse_TrkRol.dll to test tracking. So we must directly modify thesetest item in the test plan, could not load them. It is a most difficult part inthe beginning of generating the test plan, fortunately we did it. We takethe binary search method to setting the laser power and it can work. Butthis bring a problem about prolonging the test time at the same time,means cost up. We will generate the dll about concerning functionalmodule in the coming mass produce.