USB转换器范例展示一个PS2®软分离功能

ThisTechnicalBriefdescribesthecreationofaUSB

devicethatcanenumerateasamouseorasa

keyboard,dependingonwhichPS/2

®

peripheralis

pluggedintoit.TheSoftDetachprovisionofthe

PIC16C745/765supportfirmwaremakesthecreation

ofsuchadevicepossible.TechnicalBriefs,TB055and

TB056,describeindetailtheimplementationofaPS/2

toUSBmousetranslatorandaPS/2toUSBkeyboard

translator,respectively.ThisBriefwillnotdiscussthe

translationofeitherofthesetwodevices.Itfocuseson

theSoftDetachfunctionandmodifyingthedescriptor

jumptableforadevicewithmultiplesetsofdescriptors.

TB058DemonstratingtheSoftDetachFunctionWithaPS/2toUSBTranslatorExampleSoftDetachisoneofthemostusefulfeaturesonAuthor:RestonConditMicrochip'sPIC16C745/765USBmicrocontroller.TheMicrochipTechnologyInc.reasontheSoftDetachcommandissouseful,isthat,inapplicationssuchasthisone,nospecialdriverneedstobecreatedforthehost.ThemoretypicalINTRODUCTION