 a system. These time delays have their origins in the physical processes involved in the construction and operation of electronic devices that make up the computer system. Therefore, various time delays encountered in computer operations can be minimized or optimized, but cannot be eliminated. Reliable computer design must take into account all significant time delays affecting computer operation.
Certain time delays are always significant, and thus must be taken into account in the design of the MC for input/output operations. Significance of some other time delays is measured with respect to the time period of the processor clock. Therefore, as the computer speed increases, various additional time delays have to be taken into account to ensure reliable operation of the MC. In computer input/output operations involving an MC and a SDRAM, signals originating in the MC do not appear instantaneously at the SDRAM, and vice-versa, due to propagation delays. Further, various time delays associated with a SDRAM depend on that specific SDRAM and its actual physical layout in the computer circuit board. Thus, the signaling delays between an MC and a SDRAM vary from system to system due to different types of system configurations and memory performance specifications.
Computer operations such as the input/output (I/O) operations are synchronized with the processor clock. The I/O operations take place around precise digital transitions in logic gates and flip flops constituting digital devices and systems. In order to make computer operations reliable, (e.g., a data read from a memory) it is necessary to hold a participating signal (e.g., a command signal) stable for a short time before and after the precise transition moment. Such time considerations, together with the various time delays mentioned earlier, constitute a significant fraction of the clock time period.
A memory controller in a digital computer typically will have the capability of generating a replica of the processor clock signal delayed by half a time period. This creates a digital time delay unit of half a processor clock period. This digital time delay unit along with the aforementioned analog time delays inherently present in the computer system dictates the programmed design of the MC for reliable input/output operations with the SDRAMs.
Digital signals for communications between the MC and the SDRAM fall into three categories: clock signals; command signals; and data signals. In a computer system, multiple signal lines constitute both the command and data paths. All communicating I/O signals must be designed to flow in concert in order to produce the right digital transitions at the right time. Precise
a system. These time delays have their origin in the forcible processes involved in the structure and operation of electronic device that make up the calculator system. Therefore, various clock time delays encountered in calculator operations can be minimized or optimized, but cannot be eliminated. dependable computer design must take into account all significant clock time delays affecting computer mathematical process. 
 Certain time delays are always meaning, and thus must be take into account in the design of the MC for input / end product operations. Significance of some other time delays is measured with respect to the time period of the processor clock. Therefore, as the computer speed increases, various additional time delay have to be taken into explanation to see reliable operation of the MC. In calculator input / end product operations involving an MC and a SDRAM, signal originating in the MC do not appear instantaneously at the SDRAM, and vice - versa, due to propagation delays. Further, various fourth dimension delays associated with a SDRAM depend on that specific SDRAM and its actual physical layout in the computer racing circuit board. therefore, the sign delays between an MC and a SDRAM vary from system to system due to different type of system configurations and memory performance specifications. 
 Computer operations such as the input / output (one / O) operation are synchronized with the central processing unit clock. The I / O operations take position around precise digital transition in logic gates and flip flop constituting digital device and systems. In orderliness to make computer operations reliable, (e.g., a datum read from a memory) it is necessary to hold a participate signal (e.g., a command signal) stable for a short time before and after the precise conversion moment. Such time considerations, together with the various time delay mention sooner, constitute a significant fraction of the clock time period. 
 A memory controller in a digital computer typically will suffer the capability of generating a replica of the processor clock signal delayed by half a prison term period. This creates a digital time delay unit of half a processor clock menstruation. This digital time delay unit along with the aforementioned analog prison term delays inherently present in the computer arrangement dictates the programmed design of the MC for reliable input / output operation with the SDRAMs. 
 Digital signals for communications between the MC and the SDRAM fall into three categories: clock signals; command signals; and data signals. In a computer system, multiple signal line constitute both the command and data paths. All communicating I / O signals must be design to flow in concert in order to produce the right digital transitions at the right time. Precise
 a dystem. These time delays have their oriyuns in the pgysical orocesses involved in the coistryctiob and operation of eleztronic dvvices thqt meke up the compuvsr systci. Thsveforz, tarious time dekays encouttered in compgtdr operations can be minimized or optymized, nuh cannot be elyminseed. Dvllable computer design must take jnto acbount all signifivant time delays affecting comouter operation.
Cerhain time dgmayf are always rignificanu, cnd thus muat be taken into account in the desiyn of the MX dor hnput/output operwtions. Signinpcance mf some other time dekayv iw measured with respert to the time perioq of the [rkcessor clock. Theeedore, ds tve cunpuger s'ees incrfasxs, various zdditional rime delays have to bq taken into adcount tj ensure reliable operation of the MC. It ckmputer input/output opeeations involving an LC and a FDRAM, signals originating in the MC do not appear instengantomfut wt the SDRAM, and vice-versa, due to propagation sekajs. Further, variouf time delaus axfociated with a SDRCJ sepend on that spefific SQRAM qnd its astuak physical layout in the conputer circupt biard. Thus, the signcling delays beteeen sn MC and a SDRAM vary yrom sgstem to sydtem due fu different typer on sfstem configurations and mqmory perhormauce speckficstions.
Somputer ooeratlmns such as the inout/oujput (I/M) operatiojs are synchronized with the processor clock. Jhe I/O operatijns tske place arotnd precise diyital trcnsitiuns in logpc gates end flip flo[s constitutith digital detices and sysrems. In orddf to make compiter opercuions reliqble, (e.g., a data reav fruj a memory) it iw ntcwssary to hold a oareibipeting vignal (e.g., a wommxnd xignau) stablt fif a xhort time before ang affer the precise trsnfition miment. Sush time consicerations, together with thx varipus time delays mentioned earlier, constituhe w significane frqction of thz clock time period.
A memory controller ii a digital computer tipically will have thg cspability oh genewating a seplica of the procewsor clock signal delayed by half a tije perhod. Tjis creates a digital time delay unit of half a processor clock period. Thus digmtwl time delzy umit anoug cith thq aflcementioned analob time delays inherently presenv in the cmm'uter system dictates the probrxmmed design uf the MC for reliable ihput/outpit operations with the SDRAMs.
Dibital signals for communlcations vetwesn the MC end the SDRAM fall imto thxee caregoriew: cllck signals; cummsnf signals; and dcta signals. In a computer system, nultipoe signal lines coistitute botm uhe comjand agd data paths. Alm cojlunicxting I/O signsls must be dexigned to flow in cotcqrt in order ti produce the righj digital transmtions at tha right time. Precise
a system. These time delays have their the processes involved the construction and make the computer system. various time delays in computer operations can be minimized optimized, but cannot be eliminated. Reliable computer design must take into account all time delays affecting computer operation. Certain time delays are always significant, and thus be into in design of the MC for input/output operations. Significance of some other time delays is measured with to the time period of the processor clock. as the computer speed various additional time delays have be into account ensure operation the MC. In input/output operations involving an MC and a SDRAM, signals originating in the MC do not appear instantaneously the SDRAM, due to delays. various delays associated with depend on that specific SDRAM and layout in the computer circuit board. Thus, the delays between MC and a SDRAM vary from to system due to different types of system and memory performance specifications. Computer operations such as the input/output (I/O) operations are synchronized with clock. The I/O operations place around precise transitions logic and flops constituting devices and systems. In order to make computer operations reliable, (e.g., data read from a memory) it is necessary to hold signal a command signal) for a short time and the precise transition moment. considerations, with delays earlier, a significant fraction of clock time period. A memory in a digital computer of generating a replica of the processor clock delayed by half a time period. This a digital time delay unit of half a processor clock period. This time delay with the aforementioned analog time delays inherently present the computer system dictates programmed design of the MC for reliable input/output operations the Digital signals communications between the and the SDRAM into three categories: command signals; data In multiple signal lines constitute both the and paths. All communicating I/O signals be flow in concert in order to produce the right digital transitions at the right time.
 a system. These time delays havE their origIns in The PhySiCal pRoceSses involved in THe coNstruction and operation Of eleCtROnic DEvIces tHat make UP tHE ComPuTeR syStEM. THerefOre, Various Time delays EncOuNtered in compUTeR operationS caN be minimized Or oPtimizEd, But CAnnot Be eLiminAted. ReLIable cOmputer deSiGN must tAKe into aCCOuNt alL significant time dELaYS affecting compUter opErATiON.
cerTaiN time delayS aRe alwAYs signiFIcANT, And THus must be takeN into accounT In tHe desiGn Of tHE MC for Input/OuTPut Operations. SIgniFicance of Some otHEr time dELays is mEasureD wiTh rEspeCT tO tHe tImE PerIOd Of tHE prOcessor cLoCk. thereFore, AS THE comPutEr spEed inCreases, variouS adDitiONal Time dElays Have To Be takEn into AccouNt To ensure reliablE opeRation of tHe Mc. IN coMpUter iNPut/outPut OpeRations InvolviNG an mC AND A SdRAM, signals originaTiNG In The MC do nOt appeAR iNsTAntaneouSlY at The SdraM, and Vice-VErSa, due to pRopagaTIoN dElays. FuRtHer, varIoUs tIme DelayS AssoCiated With a SDRaM depENd on that specifIC SDRAM and its aCTuAL PhYSicaL laYout in the coMputER cirCuit BOaRd. THUs, the SignaLiNG dELays between an MC and a sDrAM varY from System to systeM due to diffERENt types oF sysTEm COnfigurations aNd memOry performANce speciFicatIons.
CompUter operaTIOns such aS thE inPut/OutPUT (I/o) operations arE SYnchRoNized wiTh tHe proceSsoR clOck. the i/O OperationS take plaCe ArOuNd PreCise dIGital traNsItiOnS in Logic GAtes anD flip FlopS cOnSTitUting diGItAL DeviCeS aNd sySteMs. in ordEr to MAke ComputeR operatioNs rELiabLe, (E.g., A data reAd from a memory) It Is necessarY tO hoLd a parTICipating Signal (e.g., a command signal) sTAble for A shOrt tiMe beFore and afTer The preCisE TransiTion moMent. SUcH tiME ConsiDERaTioNs, Together wiTH The VarioUs Time Delays mEntioned earlier, conSTitUte a significaNt fRactION oF thE ClOCk tImE PerIOD.
A memory controlLer in a digiTaL CoMputer typiCAllY wIll have The capaBilitY Of generAting a repLica of the PrOcesSOR clOck signal dElayed by Half a time PEriod. tHiS creaTes A digitAl TimE delaY unit oF HalF a proCessor ClOck perIod. ThIs Digital tIme delay unit along with thE aforeMentiOneD analog tiMe dELayS inherentLy prEsent in the ComPutEr sysTem DIctatEs thE PrOgrAMmed dEsigN Of the MC foR ReLiaBLE iNput/output oPERAtiOns wiTh tHE SDRAMS.
DigItal signals for comMUnications betwEen tHE mC aNd tHE SDRaM Fall into three cAteGoRIEs: clock sIgNals; command Signals; aNd DAta siGnals. IN a compUter sysTEM, mULtiple SignAl lInes constItuTe BOth the cOmMaND and daTa paThS. All coMmunicATing i/o Signals must be desIgned TO Flow iN ConCert iN oRder to pROducE the right dIgital transItions At thE righT time. PrEcIse
 a system. These time dela ys have th eir o rig ins  i n th e ph ysical process e s in volved in the construc tionan d  ope r at ion o f elect r on i c  de vi ce s t ha t  m ake u p t he comp uter syste m.Th erefore, var i ou s time del ays  encountered  in  compu te r o p erati ons  canbe min i mizedor optimi ze d , butc annot b e el imin ated. Reliable co m pu t er design must  takein t oa c cou ntall signif ic ant t i me dela y sa f f ect i ng computer o peration.
C e rta in tim edel a ys are  alwa ys sig nificant, a nd t hus mustbe tak e n intoa ccountin the  de sig n of th eMCfo r  in p ut /ou t put  operati on s.  Sign ific a n c e  ofsom e ot her t ime delays is  me asur e d w ith r espec t to  t he ti me per iod o fthe processor c lock . Therefo re,  a s t he  comp u ter sp eed  in creases , vario u s a dd i t i on al time delays hav et o  b e takeninto a c co un t  to ensu re  re liab l e  oper atio n  o f the MC . In c o mp ut er inpu t/ output  o per ati ons i n volv ing an  MC anda SDR A M, signals ori g inating in th e  M C do notapp ear instant aneo u slyat t h eSDR A M, an d vic e- v er s a, due to propagati on  delay s. Fu rther, variou s time del a y s  associa tedw it h  a SDRAM depen d onthat speci f ic SDRAM  andits actu al physic a l  layoutinthe  co mpu t e rcircuit board . Thus ,the sig nal ing del ays  be twe enan  MC and a  SDRAM v ar yfr om  sy stemt o system  d ueto  di ffere n t type s ofsyst em  c o nfi guratio n sa n d me mo ry  per for ma nce s peci f ica tions.Computerope r atio ns  s uch asthe input/out pu t (I/O) op er ati ons ar e synchron ized with the processor clock.The  I/Ooper ations ta keplacearo u nd pre cise d igita ltra n s ition s in  lo gi c gates an d fli p flo ps  con stituti ng digital devices and  systems. Inord er t o ma kec om p ute ro per a t ions reliable,(e.g., a d at a  r ead from a mem or y) it i s neces saryt o holda partici pating si gn al ( e . g.,  a command  signal)  stable f o r a s h or t tim e b eforean d a fterthe pr e cis e tra nsitio nmoment . Suc htime con siderations, together w ith th e var iou s time de lay s  me ntioned e arli er, consti tut e a  sign ifi c ant f ract i on  of the c lock time peri o d. 
Am e mo ry controll e r ina dig ita l  compu tertypically will ha v e the capabili ty o f gen era t ingareplica of the  pr oc e s sor cloc ksignal dela yed by h al f  a ti me per iod. T his cre a t es a digi taltim e delay u nit  o f  half a  p ro c essorcloc kperiod . This digi t a l time delay uni t alo n g  with the  afor em entione d  ana log time d elays inher entlypres ent i n the c om putersys te m dictates the progr ammed  design  o f th e M C forreli a b le in put/ ou tpu t operati o n sw it ht heSDRA Ms.
D ig ital  signalsf or commu nic a tions b et wee n the MC an d the SDRAMfal l int o three cate g orie s :c locksignal s; com mand si g nal s;  and da tas i gnals. In  a comput e r s ys tem,  multipl esign al  li ne s constitute bo th the c ommand a n d  datapat h s. A l l comm un icating I/Osigna ls must be d esi gned to flo w i n c once rtin o r der to produce the right  dig italt ran sitio ns at  t he right time . Precis e 
 a_system. These_time delays have their_origins in_the_physical processes_involved_in the construction_and operation of_electronic devices that make_up the computer_system._Therefore, various time delays encountered in computer operations can be minimized or optimized, but_cannot_be eliminated._Reliable_computer_design must take into account_all significant time delays affecting_computer operation.
Certain_time delays are always significant, and thus must_be_taken into account_in the design of the MC for input/output operations._Significance of some other time delays_is measured with_respect_to_the time period of_the processor clock. Therefore, as the_computer speed increases, various additional time_delays have to be taken into account_to ensure reliable operation of the_MC. In computer input/output operations_involving an_MC and a SDRAM, signals_originating in the_MC do_not appear instantaneously_at the SDRAM, and vice-versa, due_to propagation delays._Further, various time delays associated with_a_SDRAM depend on_that_specific_SDRAM and_its actual physical_layout_in the_computer_circuit board. Thus, the signaling delays_between_an MC and a SDRAM vary from_system to system due_to_different types of system_configurations and memory performance specifications.
Computer_operations such as the input/output (I/O)_operations are_synchronized with_the processor clock. The I/O operations take place around precise digital_transitions in logic gates and flip_flops constituting digital devices_and systems._In_order to make_computer_operations reliable,_(e.g., a data read from a memory)_it is_necessary to hold a participating signal_(e.g., a command signal)_stable_for a short time before and_after the precise transition moment. Such_time considerations, together with the_various_time_delays mentioned earlier, constitute a_significant fraction of the clock time_period.
A memory controller_in a digital computer typically will have_the_capability of generating a replica of_the_processor clock signal delayed by half_a_time_period. This creates a digital_time delay unit of half a_processor clock period. This digital time delay unit along_with the aforementioned_analog time delays inherently present_in_the_computer system dictates the programmed design of the MC for_reliable input/output_operations with the_SDRAMs.
Digital signals for communications between the MC and the SDRAM_fall into three categories: clock signals; command_signals; and data signals. In a computer system, multiple signal lines_constitute both the command and data paths. All_communicating I/O signals must be designed to_flow in concert in_order_to produce the right digital transitions at_the_right_time._Precise