www.德州仪器.com
SERIALCONTROLINTERFACE
REGISTERWRITEOPERATION
r0001-02
IDX6
MSB LSB
IDX5
idx4r/w IDX3 IDX2 IDX1 IDX0 D7 D6 D5 D4 D3 D2 D1 D0
寄存器 index (或者 地址) 寄存器 数据
读/write 运作
0 = write 运作
1 = 读 运作 (寄存器 index 是 ignored)
IDX0
D7 D6 D4D5 D3 D2 D1 d0r/w
ML
MC
MDI X r/w
IDX6
X
IDX1IDX2IDX3IDX4IDX5IDX6
X
t0048-02
SINGLEREGISTERREADOPERATION
PCM1609A
SLES145–AUGUST2005
theserialcontrolinterfaceisa4-wiresynchronousserialportthatoperatesasynchronouslytotheserialaudio
接口.theserialcontrolinterfaceisusedtoprogramandreadtheon-chipmoderegisters.thecontrol
interfaceincludesmdo(pin33),mdi(pin34),mc(pin35),andml(pin36).mdoistheserialdataoutput,使用
toreadbackthevaluesofthemoderegisters;mdiistheserialdatainput,usedtoprogramthemoderegisters;
mcistheserialbitclock,usedtoshiftdatainandoutofthecontrolport;andmlisthecontrolportlatchclock.
allwriteoperationsfortheserialcontrolportuse16-bitdatawords.Figure24showsthecontroldataword
format.themostsignificantbitistheread/写(r/w)位.whensetto0,thisbitindicatesawriteoperation.
sevenbits,labeledidx[6:0],settheregisterindex(oraddress)forthewriteoperation.theleastsignificanteight
位,d[7:0],containthedatatobewrittentotheregisterspecifiedbyidx[6:0].
Figure25showsthefunctionaltimingdiagramforwritingtotheserialcontrolport.mlisheldatalogic-1state
untilaregisteristobewritten.tostarttheregisterwritecycle,mlissettologic-0.sixteenclocksarethen
providedonmc,correspondingtothe16bitsofthecontroldatawordonmdi.afterthesixteenthclockcyclehas
完成,mlissettologic-1tolatchthedataintotheindexedmodecontrolregister.
figure24.controldatawordformatformdi
figure25.writeoperationtiming
readoperationsusethe16-bitcontrolwordformatshowninFigure24.forreadoperations,ther/wbitisset
to1.readoperationsignoretheindexbits,idx[6:0],ofthecontroldataword.instead,thereg[6:0]bitsin
controlregister11areusedtosettheindexoftheregisterthatistobereadduringthereadoperation.位
idx[6:0]shouldbesetto00hforreadoperations.
ThedetailsofthereadoperationareshowninFigure26.第一,controlregister11mustbewrittenwiththeindex
oftheregistertobereadback.additionally,theincbitmustbesettologic-0inordertodisablethe
自动-incrementreadfunction.thereadcycleistheninitiatedbysettingmltologic-0andsettingther/wbitof
thecontroldatawordtologic-1,indicatingareadoperation.mdoremainsinahigh-impedancestateuntilthe
lasteightbitsofthe16-bitreadcycle,whichcorrespondtotheeightdatabitsoftheregisterindexedbythe
reg[6:0]bitsofcontrolregister11.thereadcycleiscompletedwhenmlissetto1,immediatelyafterthemc
clockcyclefortheleast-significantbitoftheindexedcontrolregisterhascompleted.
17
: 点此下载
