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tms320f2808,tms320f2806
tms320f2801,ucd9501
DigitalSignalProcessors
SPRS230F–OCTOBER2003–REVISEDSEPTEMBER2005
table2-2.signaldescriptions
pinno.
NAMEDESCRIPTION
(1)
PZPINGGM
#BALL#
JTAG
jtagtestresetwithinternalpulldown.trst,whendrivenhigh,givesthescansystemcontrolof
theoperationsofthedevice.ifthissignalisnotconnectedordrivenlow,thedeviceoperatesinits
functionalmode,andthetestresetsignalsareignored.
便条:donotusepullupresistorsontrst;ithasaninternalpull-downdevice.trstisanactive
hightestpinandmustbemaintainedlowatalltimesduringnormaldeviceoperation.inalow-噪音
TRST84A6
环境,trstmaybeleftfloating.inotherinstances,anexternalpulldownresistoris
高级地
推荐
.thevalueofthisresistorshouldbebasedondrivestrengthofthedebuggerpods
applicabletothedesign.a2.2-k
Ω
resistorgenerallyoffersadequateprotection.sincethisis
应用-明确的,itisrecommendedthateachtargetboardisvalidatedforproperoperationof
thedebuggerandtheapplication.(i,
↓
)
tck75a10jtagtestclockwithinternalpullup(i,
↑
)
jtagtest-modeselect(tms)withinternalpullup.thisserialcontrolinputisclockedintothetap
TMS74B10
controllerontherisingedgeoftck.(i,
↑
)
jtagtestdatainput(tdi)withinternalpullup.tdiisclockedintotheselectedregister(操作指南
TDI73C9
ordata)onarisingedgeoftck.(i,
↑
)
jtagscanout,testdataoutput(tdo).thecontentsoftheselectedregister(instructionordata)
TDO76B9
areshiftedoutoftdoonthefallingedgeoftck.(o/z8madrive)
emulatorpin0.whentrstisdrivenhigh,thispinisusedasaninterrupttoorfromtheemulator
EMU080A8
systemandisdefinedasinput/outputthroughthejtagscan.(i/o/z,8madrive
↑
)
emulatorpin1.whentrstisdrivenhigh,thispinisusedasaninterrupttoorfromtheemulator
EMU181B7
systemandisdefinedasinput/outputthroughthejtagscan.(i/o/z,8madrive,
↑
)
FLASH
vdd3vfl96c43.3-vflashcorepowerpin.thispinshouldbeconnectedto3.3vatalltimes.
test197a3testpin.reservedforti.mustbeleftunconnected.(i/o)
test298b3testpin.reservedforti.mustbeleftunconnected.(i/o)
时钟
outputclockderivedfromsysclkout.xclkoutiseitherthesamefrequency,一个-halfthe
频率,orone-fourththefrequencyofsysclkout.thisiscontrolledbythebits1,0
xclkout66e8(xclkoutdiv)inthexclkregister.atreset,xclkout=sysclkout/4.thexclkoutsignal
canbeturnedoffbysettingxclkoutdivto3.unlikeothergpiopins,thexclkoutpinisnot
placedinhigh-impedancestateduringareset.(o/z,8madrive).
externaloscillatorinput.thispinistofeedaclockfromanexternal3.3-voscillator.inthiscase,
xclkin90b5thex1pinmustbetiedtognd.ifacrystal/resonatorisused(orifanexternal1.8-voscillatoris
usedtofeedclocktox1pin),thispinmustbetiedtognd.(i)
内部的/externaloscillatorinput.tousetheinternaloscillator,aquartzcrystaloraceramic
resonatormaybeconnectedacrossx1andx2.thex1pinisreferencedtothe1.8-vcoredigital
x188e6powersupply.a1.8-vexternaloscillatormaybeconnectedtothex1pin.inthiscase,thexclkin
pinmustbeconnectedtoground.ifa3.3-vexternaloscillatorisusedwiththexclkinpin,x1must
betiedtognd.(i)
internaloscillatoroutput.aquartzcrystaloraceramicresonatormaybeconnectedacrossx1and
X286C6
x2.ifx2isnotuseditmustbeleftunconnected.(o)
重置
devicereset(在)andwatchdogreset(输出).
devicereset.xrscausesthedevicetoterminateexecution.thepcwillpointtotheaddress
containedatthelocation0x3fffc0.whenxrsisbroughttoahighlevel,executionbeginsatthe
locationpointedtobythepc.thispinisdrivenlowbythedspwhenawatchdogresetoccurs.
XRS78B8
duringwatchdogreset,thexrspinisdrivenlowforthewatchdogresetdurationof512oscclk
循环.(i/od,
↑
)
theoutputbufferofthispinisanopen-drainwithaninternalpullup(100
µ
一个,典型).itis
recommendedthatthispinbedrivenbyanopen-draindevice.
ADCSIGNALS
adcina716f3adcgroupa,channel7input(i)
adcina617f4adcgroupa,channel6input(i)
(1)i=输入,o=输出,z=highimpedance,od=opendrain,
↑
=pullup,
↓
=Pulldown
介绍
17
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