标签: 存储器校验

Manyapplicationsrequirethemicrocontrollertocal-culateachecksumontheprogrammemorytodeter-mineifthecontentshavebeencorrupted.Untilnow,theonlyfamilyofPICmicro®microcontrollerstohavethecapabilitytoreadfromprogrammemoryarethePIC17CXXXdevices.ThePIC16F87Xdevicesarethefirst14-bitcorePICmicromicrocontrollersthatareabletoaccessprogrammemoryinthesamefashionasusedwithdataEEPROMmemory.ThesedevicesareFLASHextensionsofthepopularPIC16C7Xfamily.Table1showsacomparisonbetweenthetwoPICmicromicrocontrollerfamilies.MCalculatingProgramMemoryChecksumsUsingaPIC16F87XTB026ACCESSINGMEMORYAuthor:RodgerRicheyMicrochipTechnologyInc.ThedataEEPROMandFLASHProgrammemoryarebothaccessedusingthesamemethod.Anaddressand/ordatavaluearestoredinSpecialFunctionReg-isters(SFR)andthenmemoryisaccessedusingcon-INTRODUCTIONtrolbitsinotherSFRs.TherearesixSFRsrequiredtoMany……