PIC18C ECAN ‘C’例程

TheEnhancedControllerAreaNetwork(ECAN)mod-

ule,offeredbymanyofthePIC18FfamilyofPICmicro

®

microcontrollers,isthelatestenhancementtotheexist-

inglegacyCANmodule.Devicessuchasthe

PIC18C658/858andPIC18F248/258/448/458usethe

legacyCANmodule.

ECANoffersmanyenhancementsoverthelegacy

CANmoduleintermsofmoretransmit/receivebuffers,

acceptancefilters,andhardwareFIFOoperation.At

thesametime,theECANmoduleisfullybackward

compatiblewiththelegacyCANmodule.

ECANprovidesthreemodesofoperation–Mode0,

Mode1andMode2.Mode0isfullybackwardcompat-

iblewiththelegacyCANmodule.Applicationsdevel-

opedforthelegacyCANmodulewouldcontinueto

workwithoutanychangeusingECAN.Mode1isthe

EnhancedLegacymodewithincreasedbuffersandfil-

ters.Mode2hasthesameresourcesasMode1,but

withahardwaremanagedreceiveFIFO.Givenitsfea-

turesandflexibility,ECANwouldproveusefultomany

CAN-basedapplications.

Thisapplicationnoteimplements‘C’routinestoaccess

allfeaturesoftheECANmodule.Thisdocumentdoes

notdescribeECANandtherelatedPIC18Ffamilyin

detail.Readersareencouragedtoreadthe

PIC18F6585/6680/8585/8680devicedatasheet

(DS30491)formoreinformation.AN878PIC18CECAN‘C’RoutinesAuthors:CaioGübelandNileshRajbhartiOVERVIEWOFECANMODULEMicrochipTechnology,Inc.FollowingarethemainfeaturesoftheECANmodule:FullybackwardcompatiblewiththelegacyCANINTRODUCTIONmoduleThreefunctionalmodes:TheEnhancedControllerAreaNetwork(ECAN)mod--Mode0