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Intel

®

 440GX AGPset Design Guide

3-25

Design Checklist

3.13

Flash Design

3.13.1

Dual-Footprint Flash Design

New features are coming to the PC continue to increase the size of BIOS code, pushing the limits 
of the 1 Mbit boundary. OEMs have already converted many PC designs to 2 Mbit BIOS and 
higher, and more will follow. Since it is difficult to predict when BIOS code will exceed 1 Mbit, 
OEMs should design motherboards to be flexible. Design in a dual-footprint on the motherboard 
that accepts both Intel’s 1 Mbit flash chips and 2 Mbit boot block chips. This will make the 1M-to-
2M transition easier by removing the need for PCB changes to accommodate higher density 
components. Intel provides various layout tools to help OEMs design in the dual-footprint. These 
tools are available from Intel’s BBS, WWW (http://www.intel.com/design/flcomp/devtools/
flas4.html), and literature distribution center. Look for Application Note AP-623 Multi-Site Layout 
Planning with Intel's Boot Block Flash Memory
 (Order #: 292178). This document provides 
detailed information on flexible layouts. Shown below are three of the reference layouts that Intel 
furnishes to customers. These layouts are described in AP-623 and are available electronically 
(Gerber and Postscript formats). Note the small amount of extra board space needed to implement 
the dual-footprint layouts. 

3.13.2

Flash Design Considerations

The Intel’s flash devices (GX/BL/BV/B5) use an Address Transition Detection (ATD) mechanism 
to improve their performance. When interfacing flash devices that employ the ATD mechanism, the 
designer needs to make sure that the address transition time is not more than 10 ns while CE# is 
active (low). If the address transition time is more than 10 ns invalid data can result on the data bus. 
When flash devices are interfaced to the ISA bus they can be exposed to address transitions in 
excess of 10 ns. Other types of interfacing considerations, specific to flash, can be referenced in 
Application Note AP-636 “Preventing BIOS Failures Using Intel’s Boot Block Flash Memory” 
(Order# 292192 or on WWW).

Figure 3-5. Dual Footprint Flash Layouts

PLCC32 to TSOP40

PLCC32 to PSOP44

PDIP32 to TDIP40

Содержание 440GX

Страница 1: ...Intel 440GX AGPset Design Guide March 1999 Order Number 290651 001...

Страница 2: ...any time without notice Contact your local Intel sales office or your distributor to obtain the latest specifications and before placing your product order The Intel 440GX AGPset may contain design d...

Страница 3: ...idelines 2 1 2 1 BGA Quadrant Assignment 2 1 2 2 Board Description 2 3 2 3 Routing Guidelines 2 5 2 3 1 GTL Description 2 6 2 3 2 GTL Layout Recommendations 2 6 2 3 3 Single Processor Design 2 6 2 3 3...

Страница 4: ...outing Spacing 2 32 2 9 6 2 System Bus Clock Layout 2 32 2 9 6 3 PCI Clock Layout 2 33 2 9 6 4 SDRAM Clock Layout 2 33 2 9 6 5 AGP Clock Layout 2 34 3 Design Checklist 3 1 3 1 Overview 3 1 3 2 Pull up...

Страница 5: ...erature Sensor 3 33 3 18 2 LM79 Microprocessor System Hardware Monitor 3 33 3 18 3 82558B LOM Checklist 3 34 3 18 4 Wake On LAN WOL Header 3 35 3 19 Software BIOS 3 35 3 19 1 USB and Multi processor B...

Страница 6: ...1 5 1 Processors 5 1 5 1 1 Voltage Regulator Modules 5 2 5 1 2 Voltage Regulator Control Silicon 5 2 5 2 Intel 440GX AGPset 5 3 5 2 1 Clock Drivers 5 3 5 2 2 Power Management Components 5 3 5 2 3 FET...

Страница 7: ...Layout Guidelines 2 19 2 15 On board AGP Compliant Device Layout Guidelines 2 21 2 16 FET Switch Example 2 22 2 17 Registered SDRAM DIMM Example 2 23 2 18 Matching the Reference Planes and Adding Deco...

Страница 8: ...2 16 Control Signal Line Length Recommendations 2 21 2 17 MDx lines Reference Planes Routing 2 23 2 18 FET Switch DQ Route Example 2 25 2 19 Motherboard Model SRAS_B 4 DIMMs 2 28 2 20 Motherboard Mod...

Страница 9: ...Intel 440GX AGPset Design Guide ix Revision History Date Revision Description 3 99 001 Initial Release...

Страница 10: ...x Intel 440GX AGPset Design Guide...

Страница 11: ...1 Introduction...

Страница 12: ......

Страница 13: ...anageability of desktop mobile and server systems This chapter also provides design recommendations which Intel feels will provide flexibility to cover a broader range of products within a market segm...

Страница 14: ...oper s Guide order number 243006 AP 485 CPUID Application Note WWW order number 41618 AP 585 Layout Application Note WWW order number 243330 AP 586 Thermal Application Note WWW order number 243331 AP...

Страница 15: ...grated IDE Controller with Ultra DMA 33 support PIO Mode 4 transfers PCI IDE Bus Master support Integrated Universal Serial Bus USB Controller with 2 USB ports Integrated System Power Management Suppo...

Страница 16: ...ngle and dual Intel Pentium II processor configurations 64 bit GTL based system data bus Interface 32 bit system address bus support 64 72 bit main memory interface with optimized support for SDRAM 32...

Страница 17: ...rated Graphics Port and main memory The 82443GX supports a 4 deep in order queue i e it provides support for pipelining of up to 4 outstanding transaction requests on the system bus For system bus to...

Страница 18: ...upts Chip select decoding is provided for BIOS Real Time Clock Keyboard Controller second external Microcontroller as well as 2 Programmable Chip Selects The PIIX4E provides full Plug and Play compati...

Страница 19: ...and component instrumentation Information regarding this product can be found at http developer intel com ial WfM tools ldcm index htm The WfM Baseline Instrumentation specification identifies specifi...

Страница 20: ...l Off Soft off is usually provided by a user accessible switch that will send a soft off request to the system The PIIX4 provides the power button input for this purpose and implementation details are...

Страница 21: ...ing an open drain output driver with pull ups to Vcc2 5 3 Please prepare for additional thermal margin for increases of 1 5W for higher performance or otherwise enhanced processor 4 Motherboard design...

Страница 22: ...Introduction 1 10 Intel 440GX AGPset Design Guide...

Страница 23: ...2 Motherboard Design...

Страница 24: ......

Страница 25: ...motherboard to be routed in 4 layers Figure 2 1 shows the 4 signal quadrants of the 82443GX The component placement on the motherboard should be done with this general flow in mind This simplifies rou...

Страница 26: ...actor design the AGP compliant graphics device can be either on the motherboard device down option or on an AGP connector up option 4 The trace length limitation between critical connections will be a...

Страница 27: ...between the number of DIMM sockets and other motherboard peripherals need to be evaluated for each design 2 2 Board Description For a single processor Intel 440GX AGPset motherboard design a 4 layer...

Страница 28: ...d in a Intel 440GX AGPset design If a 6 layer stack up is used then it is recommended to route most of the GTL bus signals on the inner layers The primary and secondary signal layer can be used for GT...

Страница 29: ...or a short distance on a power plane then it should be routed on a VCC plane not the ground plane Keep vias for decoupling capacitors as close to the capacitor pads as possible 2 3 Routing Guidelines...

Страница 30: ...L layout Guidelines for the Pentium II Processor and Intel 440GX AGPset for more details 2 3 2 GTL Layout Recommendations This section contains the layout recommendations for the GTL signals The layou...

Страница 31: ...Update order number 243337 Specifically erratum 42 workaround L1 4 5 Intel strongly recommends running analog simulations using the available I O buffer models together with layout information extract...

Страница 32: ...tion space plot show Intel strongly recommends that any traces that fall outside the recommended lengths be simulated to ensure they meeting timing and signal quality specs 2 3 5 Single Processor Syst...

Страница 33: ...of design flexibility must be carefully weighed against the cost savings from removing the resistors 2 3 5 2 SET Trace Length Requirements Intel has performed sensitivity analysis on the SET topology...

Страница 34: ...delines for VREF distribution and decoupling are contained in P Intel Pentium II Processor Power Distribution Guidelines There are six GTL signals that can be driven by more than one agent simultaneou...

Страница 35: ...in this section The heart of the methodology is structured around extensive simulations and analysis prior to board layout This represents a significant departure from traditional design methods The...

Страница 36: ...le paths which must be considered Intel Pentium II processor driving an AGPset component AGPset component driving a Intel Pentium II processor Intel Pentium II processor driving a Intel Pentium II pro...

Страница 37: ...lated This is necessary to ensure that signal integrity requirements are met Refer to Slot 1 Bus Termination Card Design Guidelines for details 2 3 10 Pre Layout Simulation Sensitivity Analysis After...

Страница 38: ...25 4 4 75 5 5 0 0 2 0 4 0 6 0 8 1 1 2 L1 PCa rd 1 to 82 44 0FX Se pa rati on Di stanc e i n L2 PCa rd 2 to 82 44 0FX Se par ati on Dis tance i n D U A L K LA M A TH FLIGH T TIME M AX FT LP C 2 51 inc...

Страница 39: ...fined as the difference between the delay of a signal at the input of a receiving agent measured at VREF and the delay at the output pin of the driving agent when driving the GTL reference load Howeve...

Страница 40: ...hat it meets the specification at the core NOTE 1 Ringback specifications follow the methodology described in Intel Pentium II Processor at 233 MHz 266 MHz 300 MHz and 333 MHz Datasheet Table 2 5 Syst...

Страница 41: ...Recommendations on page 4 1 Tflight max Maximum system flight time Flight time is defined in Section 4 Debug Recommendations on page 4 1 Tco max Maximum driver delay from input clock to output data Tc...

Страница 42: ...B skew spec is based on the results of extensive simulations at Intel The Tadj value is based on Intel s experience with systems that use the Intel Pentium Pro processor and Intel Pentium II processor...

Страница 43: ...een signal coupling trace spacing and line lengths These routing rules are divided by trace spacing In 1 1 spacing the distance between the traces air gap is the same as the width of the trace In 1 2...

Страница 44: ...motherboard AGP signals must be pulled up to VCC3 3 using 8 2K to 10K pull up resistors refer to Section 3 5 1 82443GX Interface on page 3 10 Pull up resistors should be discrete resistors as resisto...

Страница 45: ...rongly recommended that the clock spacing be at least four times the trace width to any strobes The clock lines on the motherboard need to be simulated to determine the their proper line length The mo...

Страница 46: ...ay Considerations Designing a reliable and high performance memory system will be challenging Careful consideration of motherboard routing and stackup topologies DIMM topology impedance and trace leng...

Страница 47: ...a low inductance path for return currents is to provide additional decoupling capacitors next to signal vias It is not possible to route all the MD lines on a single layer As a result some of the MD...

Страница 48: ...s Layout Guidelines All signals require careful routing for both min and max trace lengths Figure 2 18 Matching the Reference Planes and Adding Decoupling Capacitor Figure 2 19 4 DIMMs Single or Doubl...

Страница 49: ...uidelines Table 2 18 FET Switch DQ Route Example Figure 2 20 Motherboard Model Data MDxx 4 DIMMs v004 0 6 82443GX 1 1 2 0 0 7 2 4 0 3 1 0 0 6 FET SW 82443GX 0 7 2 4 0 4 0 6 DIMM Module 2 DIMM Module 1...

Страница 50: ...2 4 6 7 4 DIMMs Figure 2 22 Motherboard Model DQM_A 1 5 4 DIMMs 82443GX 1 0 3 25 0 4 0 6 DIMM Module 1 DIMM Module 2 0 4 0 6 DIMM Module 3 DIMM Module 4 0 4 0 6 82443GX 1 0 3 25 0 4 0 6 DIMM Module 1...

Страница 51: ...s Figure 2 24 Motherboard Model DQM_B 1 5 4 DIMMs 82443GX 1 0 3 25 0 4 0 6 DIMM Module 3 DIMM Module 4 Figure 2 25 Motherboard Model CS_A CS_B 4 DIMMs Figure 2 26 Motherboard Model SRAS_A 4 DIMMs 8244...

Страница 52: ...e 2 19 Motherboard Model SRAS_B 4 DIMMs Table 2 20 Motherboard Model SCAS_A 4 DIMMs Table 2 21 Motherboard Model SCAS_B 4 DIMMs 82443GX 1 0 3 0 0 4 0 6 DIMM Module 3 DIMM Module 4 82443GX 1 0 3 0 0 4...

Страница 53: ...e 2 22 Motherboard Model WE_A 4 DIMMs Table 2 23 Motherboard Model WE_B 4 DIMMs Table 2 24 Motherboard Model MA_A 14 0 4 DIMMs 82443GX 1 0 3 0 0 4 0 6 DIMM Module 1 DIMM Module 2 82443GX 1 0 3 0 0 4 0...

Страница 54: ...GPset PCI Bus design is basically the same as the Intel 440BX AGPset The Intel 440GX AGPset supports 5 PCI Bus masters excluding the Intel 440GX AGPset and PIIX4E by the support of 5 PREQ and PGNT lin...

Страница 55: ...aced at the corners of the 443GX BGA Package A minimum of four 0 1uF and four 0 01 uF are recommended The system bus AGP PCI and DRAM interface can break out from the BGA package on all four sides Add...

Страница 56: ...be maintained between the clock traces and other traces A minimum spacing of 0 018 is recommended for serpentines 2 9 6 2 System Bus Clock Layout System bus clock nets should be routed as point to poi...

Страница 57: ...sed to drive DCLKWR at the 82443GX The single clock net should be T d as close as possible to the 82443GX An additional capacitive load of 20pF is also required The capacitor should also be located as...

Страница 58: ...ngth Note One driver The signal splits at the 82443GX each half of the trace goes through a 22 Ohm resistor and then to their respective loads If the graphics chip is down on the motherboard the trace...

Страница 59: ...3 Design Checklist...

Страница 60: ......

Страница 61: ...tions RC rise time etc Analysis should be done to determine the minimum maximum values that may be used on an individual signal Engineering judgment should be used to determine the optimal value This...

Страница 62: ...t A 31 3 to 82443GX A20M 150 ohm 330 ohm pull up to 2 5V ADS UP Connect to 82443GX DP Connect CPUs and 82443GX AERR Leave as NC AP 1 0 Leave as NC BCLK Connect to CK100 22 ohm series resistor BERR Lea...

Страница 63: ...100 22 ohm series resistor PICD 1 0 UP 150 ohm pull up to 2 5V DP Connect CPUs and IOAPIC and 150 ohm pull up to 2 5V PRDY 240 ohm series resistor to ITP PREQ Connected to ITP 330 ohm pull up to 2 5V...

Страница 64: ...DP Separate 47 ohm series resistors then hooked together to ITP 1K ohm pull up to 2 5V TRDY UP Connect to 82443GX DP Connect CPUs and 82443GX TRST UP Connect to ITP 680 ohm pull down DP Connect CPUs...

Страница 65: ...5 even if an I O APIC is not being used See the Debug Recommendations for further information that may affect these resistor values All CMOS inputs should be pulled up to Vcc2 5 150 ohm to 10K ohm See...

Страница 66: ...two regulator outputs together with a wide trace that runs the along the same basic path as the GTL signals beware of crosstalk VREF should be generated at each AGPset component from this combined VTT...

Страница 67: ...II processors Each processor site should have an isolated VccCORE power plane Contact your VRM vendor for availability of VRMs with current sharing capabilities if desired The SLOTOCC signal can be u...

Страница 68: ...rs 22 ohm series resistors are recommended on the CPU PCI and IOAPIC clock outputs In a UP system clock skew between the 82443GX and the CPU can be reduced by tying the clock driver pins together at t...

Страница 69: ...ementation of the 16 bit flip flop for CKE generation for 4 DIMMs GCKE trace length from the 82443GX to the flip flop is recommended to be 1 MIN to 4 MAX CKE trace lengths from the flip flop to the DI...

Страница 70: ...00 ohm resistor at both 82443GX and PIIX4E CPURST Connected to CPUs and ITP 240 ohm series resistor CRESET 10K ohm pull up to 3 3V Controls the mux for the CPU strapping signals CSA 5 0 Connect to DIM...

Страница 71: ...through 22 ohm series resistor PGNT 4 0 8 2K ohm pull ups to 3 3V Connected to PCI connectors PHLDA 8 2K ohm pull up to 3 3V Connected to PIIX4E PHOLD 8 2K ohm pull up to 3 3V Connected to PIIX4E PIPE...

Страница 72: ...internal pull up may prove to be sufficient however the first rev of boards should include the external pull up to be safe 3 5 2 82443GX GTL Bus Interface The Intel 440GX AGPset does not support the...

Страница 73: ...ooks to a unique input on the PIIX4E It is recommended that the interrupts be staggered It is also recommended that each PIRQ be programmed to a different IRQ if possible It is the requirement of the...

Страница 74: ...1 0 dated Feb 1998 shows pin 81 of the DIMM module is the WP write protect pin for the SPD EEPROM The block diagrams show there is a 47K pull down resistor tied to the WP pin This allows the DIMM man...

Страница 75: ...ndors 12 functional units per part requires 6 devices on motherboard 3 6 3 Registered SDRAM There may be power and thermal considerations for registered DIMMs If a design is going to support registere...

Страница 76: ...8 2K ohm pull up to 3VSB CONFIG2 8 2K ohm pull down CPURST Leave as a NC CPU_STP GPO17 No connect or connected to CK100 with 10K ohm pull up to 3VSB DACK 7 0 Connect to ISA slots DACK 3 0 also connec...

Страница 77: ...CS No connect MEMCS16 Connected to ISA slots 1K ohm pull up to VCC MEMR MEMW Connected to ISA slots and Flash 8 2K ohm pull up to VCC DP Connected to IOAPIC NMI Part of CPU bus frequency circuit 2 7K...

Страница 78: ...0 19 Connected to ISA slots Ultra I O Flash LM79 8 2K ohm pull up to VCC DP Connected to IOAPIC SBHE Connect to ISA slots SCS1 Connected to IDE connector through 33 ohm series resistor SCS3 Connected...

Страница 79: ...ontrol with 10K ohm pull up to VCC3 SUSB GPO15 No connect SUSC GPO16 Controls ATX power supply SUSCLK No Connect SUS_STAT 2 1 GPO 21 20 No Connect SYSCLK Connect to LM79 and ISA slots TC Connect to SI...

Страница 80: ...n the motherboard ground and hard disk drives 3 7 2 2 Motherboard 1 PIIX4E Placement The PIIX4E should be placed as close as possible to the ATA connector s 2 Resistor Location When the distance betwe...

Страница 81: ...ement for trace lengths not exceeding 4 inches Note that if the trace length between the PIIX4E and the IDE header exceeds 4 inches the series resistors should be placed within 1 inch of the PIIX4E Th...

Страница 82: ...ty The Schottky diode will begin to conduct first therefore carrying the high current VREF can be tied to Vcc in a non 5V tolerant system Tie Vss and Vss USB to ground 3 8 PCI Bus Signals A specific b...

Страница 83: ...tion 0 offset B0h B3h The LM79 is connected to the X Bus due to the functionality of the PGCS 1 0 pins on the PIIX4E Table 3 10 Non PIIX4E PCI Signals SIGNAL CONNECTION ACK64 PERR PLOCK REQ64 5V PCI e...

Страница 84: ...efore the PIIX4E should be located at close as possible to the ATA connectors to allow the IDE cable to be as long as possible Use ISA reset signal RSTDRV from PIIX4E through a Schmitt trigger for RES...

Страница 85: ...Flash Memory Order 292178 This document provides detailed information on flexible layouts Shown below are three of the reference layouts that Intel furnishes to customers These layouts are described...

Страница 86: ...tel s flash devices in desktop designs Simplified 2 7 3V 5V Design Considerations Following are general layout guidelines for the Intel s SmartVoltage Smart 5 boot block flash memory 2 4Mbit BV B5 in...

Страница 87: ...ignal to drive flash RP to keep device in deep power down during power up only write protection For systems not needing power saving modes Connect BYTE to GND for byte wide mode operation if x16 devic...

Страница 88: ...to logic on the board without first going through a Schmitt trigger input to square off and maintain its signal integrity PS_POK logic from the power supply connector can be powered from the core volt...

Страница 89: ...logic and pull ups in the path of PWRGOOD to the CPU and PWROK to the PIIX4E with the above exception can be powered from the core supply The PWROK signal to the chipset is a 3V signal The core well p...

Страница 90: ...e used Refer to the schematics for implementation details RI can be connected to the modem if this feature is used To implement ring indicate as a wake event the source driving the RI signal must be p...

Страница 91: ...With the exception of GPI1 all unused GPIx inputs on the PIIX4E should be tied high through pull up resistors 8 2K ohm 10K ohm to a power plane Tying directly to the power plane is also acceptable GP...

Страница 92: ...r from the PIIX4 reduces its effectiveness 3 17 82093AA IOAPIC An I O APIC is required for a DP system and is optional for a UP system The I O APIC is a 5V device All Vcc pins must be connected to 5V...

Страница 93: ...hat selects between APIC OS IRQ20 and PIC OS IRQ9 so the BIOS can properly report to the OS which interrupt is assigned to the SCI The SMI signal from the PIIX4 PIIX4E should be connected directly to...

Страница 94: ...ic is needed to ensure that at least 4 clock cycles occur between ALTRST and ISOLATE assertion The distance between Magnetics i e Cat 3 or Cat 5 wire and RJ 45 connector should be kept to less than on...

Страница 95: ...Intel Pentium II processor as early as possible in the POST during system boot up The BIOS update signature mechanism should be used to validate that the BIOS Update has been accepted by the processo...

Страница 96: ...erature measured 0 3 above the center of the fan See the Intel Pentium II Processor Datasheet for the TPH Specification Verify that all major components including the 82443GX can be cooled the way the...

Страница 97: ...especially if the layout guideline recommendations in this document are not followed It is recommended that simulations be performed to ensure proper timings and signal integrity is met especially if...

Страница 98: ...t run in parallel separate them on different layers with a well decoupled power or ground plane If they must run parallel on the same layer then separate the traces by a minimum of 25 mils Proper oper...

Страница 99: ...4 Debug Recommendations...

Страница 100: ......

Страница 101: ...a way to connect your logic analyzer to signals on the processor system bus They are available from two logic analyzer vendors Hewlett Packard Co for their HP 16500B series logic analyzers Contact you...

Страница 102: ...2 5 FLOTHERM Model A FLOTHERM Model is available for the Intel Pentium II processor 4 3 Debug Features These suggestions are for debug purposes only on initial prototype systems and are not required f...

Страница 103: ...nput current leakage input timings etc The resulting values may conflict As a result of the extra loading the following compromise pull ups to Vcc 2 5 are recommended The actual value required by your...

Страница 104: ...ection See the Integration tools chapter of the processor datasheet for schematics and a signal checklist Be sure it is the proper 0 050 x 100 1 27mm x 4mm spacing connector Provide the capability to...

Страница 105: ...ed the tool in this file This file needs to change based on what components are in the boundary scan chain In DP systems the processor with PREQ0 and PRDY0 is considered processor 0 even if it is not...

Страница 106: ...the deassertion of RESET if BIST is not configured to run If BIST is configured to run BNR will continue to toggle until BIST completion After BNR stops toggling the PICD 1 0 signals begin the MP init...

Страница 107: ...5 Third Party Vendors...

Страница 108: ......

Страница 109: ...vailability pricing and compatibility 5 1 Processors Table 5 1 Slot 1 Connector Supplier Contact Phone AMP Incorporated Mike Mullen 717 592 2352 Framatome Connectors Leonard Dore 717 767 8006 Foxconn...

Страница 110: ...aurice Lee 886 2 7164822 x233 Taiwan 510 770 0660 x111 LinFinity Andrew Stewart 714 372 8383 Raytheon Hubert Engle Brechten 415 962 7982 Semtech European CNDA Alan Moore 805 498 2111 x291 VXI Electron...

Страница 111: ...ardware monitor will be used to monitor voltage regulation and fan RPM 5 2 3 FET Switches 4 DIMM FET Design Intel is recommending that OEMs contact the particular vendor for pricing and availability o...

Страница 112: ...n mechanism retention mechanism attach mount and heat sink supports 5 3 3 Heat sinks Public information see Intel Pentium Processor Support Components Web page Mechanical dimensions are public an MP C...

Страница 113: ...A Reference Design Schematics...

Страница 114: ......

Страница 115: ...he EMI signals A thermal sensor the MAX 1617 ME which connects to an internal processor diode has been included to monitor processor temperature Intel Pentium II Slot 1 processor connector part 2 4 an...

Страница 116: ...ws the 82443GX component Memory and System Data Bus Interfaces GTL_REF signal are also shown on this page Ideally the GTL_REF signals should be decoupled separately and as close as possible to the 824...

Страница 117: ...vides logic level transitions for the PIIX4E Note the placement requirements for the capacitors and series resistors at the bottom left Flash BIOS Component 27 This page shows the 28F002BC T Flash BIO...

Страница 118: ...s speed and quieting the system Pull up and Pull down Resistors 34 35 These pages show pull up and pull down resistors for PCI signals PIIX4E Slot 1 CMOS ISA and AGP signals Also shown are spare gates...

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