MCP23X0817 GPIO独特扩展的功能

GPIOexpandersprovideeasyI/Oexpansionusing

standardserialinterfaces.GPIOproductsareusedto

increasetheI/OonanMCUorprovideremoteI/O

usingaserialinterface.

Thisapplicationnotediscussesthefeaturesetanduse

oftheMCP23X08/17(8-bitand16-bit)GPIOExpand-

ers.

TheMCP23X08are8-bitGPIOExpanders:

•MCP23008:I

2

C™Interface

•MCP23S08:SPIInterface

TheMCP23X17are16-bitGPIOExpanders:

•MCP23017:I

2

CInterface

•MCP23S17:SPIInterface

ThefunctionsandfeaturesoftheMCP23X08and

MCP23X17arebasicallythesame,exceptwhere

otherwisenoted.AN1043UniqueFeaturesoftheMCP23X08/17GPIOExpandersAuthor:PatRichardsI/OPORTDESCRIPTIONMicrochipTechnologyInc.TheI/Oportishighlyconfigurableformaximumflexibility.Figure1isasimplifiedblockdiagramofanINTRODUCTIONI/Oportpin.Theportcaneitherdrivelogiclevelsonthepin,orreadlogiclevelsfromthepad.ThelevelontheGPIOexpandersprovideeasyI/Oexpansionusingpadcanbereadatanytime,regardlessifthepinisstandardser