an nucseries usb massstorage sc應(yīng)用注解和示例程序

ApplicationNoteofNUVOTON32-bitNuMicro?Application32-bitCortex?-M0MCUNuMicro?Family February25,-i Rev.簡(jiǎn) 目標(biāo)讀 例子功 代碼片 主函數(shù)main(見 輪詢流程(見 調(diào)用過(guò) API用法參 測(cè)試 結(jié) 版本歷 本文利用AN_1020_EN.ZIP“Smpl_UDC”項(xiàng)目，闡述了用相關(guān)如何USB庫(kù)和源代碼，創(chuàng)建一個(gè)USBMassStorage設(shè)備的辦法。本文向程序員闡述了如何實(shí)現(xiàn)一個(gè)USB應(yīng)用的過(guò)程，文章假定讀者熟悉USB(UniversalSerialBus)支持自定義VID(VendorIDPID(Product在硬件相關(guān)設(shè)定完成后，需要調(diào)用udcInit()重置并且初始化USB的端點(diǎn)狀態(tài)。udcInit同時(shí)也會(huì)檢查USB在USB初始化完成后，調(diào)用udcFlashInit()初始化相關(guān)的設(shè)備。用戶如果要用自定義的設(shè)備，最后一步將調(diào)用MsBk()。MsB()通過(guò)不斷的輪詢B的狀態(tài)發(fā)現(xiàn)B，一旦發(fā)現(xiàn)有US調(diào)的理行。int32_tint32_t{/*InitializeUSBDevicefunction*//*Initializemassstoragedevice*//*StartUSBMassStorage*/return}正如您看到的，函數(shù)ssB()中只有一個(gè)循環(huán)不斷地調(diào)用函數(shù)sIsr()。sIsr()并不是真正的中斷處理寒暑。將ssr()放在主進(jìn)程中運(yùn)行，看起來(lái)簡(jiǎn)單易懂，又能實(shí)現(xiàn)功能。（更復(fù)雜的應(yīng)用場(chǎng)sIsr）voidvoid{/*HandlertheUSBISRbypolling*/{}}void{uint32_tu32EVF=_DRVUSB_GET_EVF();if(u32EVF&EVF_FLD){/*HandletheUSBattached/detachedevent*/}elseif(u32EVF&{/*HandletheUSBbusevent:Reset,Suspend,andResume*/}elseif(u32EVF&{/*HandletheUSBProtocol/Claseevent*/}}在所有的響應(yīng)函數(shù)中，有兩個(gè)函數(shù)尤其重要，它們是BkOck和sBIck，這兩個(gè)函數(shù)會(huì)被ss()調(diào)用到。這兩個(gè)函數(shù)完成了和主機(jī)B的大部分?jǐn)?shù)據(jù)通信工作。作為一個(gè)BMsstre設(shè)備需要支持的SI命令，也是由sBOck和skIck實(shí)現(xiàn)的。在我們的例子代碼里，這些SSsrctWOP(更進(jìn)一步，如果用戶可以嘗試“u8OPCode”的值，并加入地或自定義的SCSI命令的支持。Windows用戶要獲知如何在程序里發(fā)送SCSI命令的辦法，請(qǐng)到網(wǎng)絡(luò)上搜索關(guān)鍵字DeviceIOControl和voidvoidSpiRead(uint32_taddr,uint32_tsize,uint32_t{/*ThisislowlevelreadfunctionofUSBMassStorage}voidSpiWrite(uint32_taddr,uint32_tsize,uint32_t{/*ThisislowlevelwritefunctionofUSBMassStorage}uint8_tGetGetUSBeventH/WSetSetUSBInitMassStrogeSetUSBInitstorageHandleprotocolorclasseventUSBDriverReference您可以用KeilMDK編譯并運(yùn)行該USBMassStorage的示例代碼(Smpl_UDC)。在KeilMDK下運(yùn)行的時(shí)候，需要一塊NUC1xx系列開發(fā)板和一個(gè)ICE。.如果程序已經(jīng)燒錄在Flash中了，用戶重啟動(dòng)開發(fā)March11,1.InitiallyImportantNuvotonproductsarenotdesigned,intended,authorizedorwarrantedforuseascomponentsinsystemsorequipmentintendedforsurgicalimntation,atomicenergycontrolinstruments,airneorspaceshipinstruments,transportationinstruments,trafficsignalinstruments,combustioncontrolinstruments,orforotherapplicationsintendedtosupportorsustainlife.Furthermore,NuvotonproductsarenotintendedforapplicationswhereinfailureofNuvotonproductscouldresultorleadtoasituationwherein alinjury,deathorseverepropertyorenvironmentaldamagecouldoccur.NuvotoncustomersusingorsellingtheseproductsforuseinsuchapplicationsdosoattheirownriskandagreetofullyindemnifyNuvotonforanydamagesresultingfromsuchimproperuseorsales.Pleasenotethatalldataandspecifi