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3.3on-chipram
3.4on-chipmemorysecurity
TMS320VC5409A
fixed-pointdigitalsignalprocessor
SPRS140F–NOVEMBER2000–REVISEDJANUARY2005
thestandardon-chipromlayoutisshownintable3-1.
table3-1.standardon-chipromlayout
ADDRESSRANGEDESCRIPTION
c000h-d4ffhromtablesforthegsmefrspeechcodec
d500h-f7ffhreserved
f800h-fbffhbootloader
fc00h-fcffhµ-lawexpansiontable
fd00h-fdffha-lawexpansiontable
fe00h-feffhsinelook-uptable
ff00h-ff7fhreserved
(1)
ff80h-ffffhinterruptvectortable
(1)inthe5409arom,128wordsarereservedforfactorydevice-testingpurposes.applicationcodeto
beimplementedinon-chiprommustreservethese128wordsataddressesff00h-ff7fhin
programspace.
the5409adevicecontains32k-文字
×
16-bitofon-chipdual-accessram(daram).
thedaramiscomposedoffourblocksof8kwordseach.eachblockinthedaramcansupporttwo
readsinonecycle,orareadandawriteinonecycle.fourblocksofdaramarelocatedintheaddress
range0080h-7fffhindataspace,andcanbemappedintoprogram/dataspacebysettingtheovlybit
toone.
the5409adevicehasamaskableoptiontoprotectthecontentsofon-chipmemories.whentherom
protectbitisset,noexternallyoriginatinginstructioncanaccesstheon-chipmemoryspaces;hpiwrites
havenorestriction,buthpireadsarerestrictedto4000h-5fffh.
FunctionalOverview
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