Lists the combination of control pin assertion for | Compaq EV68A

Bcache Port

4.8.4.1 BcAdd_H[23:4]

The BcAdd_H[23:4] pins are high drive outputs that provides the index for the Bcache. The 21264/EV68A supports Bcache sizes of 1MB, 2MB, 4MB, 8MB, and 16MB. Table 4–42lists the values to be programmed into Cbox CSRs BC_ENABLE[0] and BC_SIZE[3:0] to support each size of the Bcache.

Table 4–42 Programming the Bcache to Support Each Size of the Bcache

BC_ENABLE[0]	BC_SIZE[3:0]	Bcache Size

1	0000	1MB
1	0001	2MB
1	0011	4MB
1	0111	8MB
1	1111	16MB

When the Cbox CSR BC_BANK_ENABLE[0] is not set, the unused BcAdd_H[23:4] pins are tied to zero. For example, when configured as a 4MB cache, the 21264/EV68A never changes BcAdd_H[23:22] from logic zero, and when BC_BANK_ENABLE[0] is asserted, the 21264/EV68A drives the complement of the MSB index on the next higher BcAdd_H pin.

4.8.4.2 Bcache Control Pins

The Bcache control pins (BcLoad_L, BcDataWr_L, BcDataOE_L, BcTagWr_L, BcTagOE_L) are controlled using Cbox CSRs BC_BURST_MODE_ENABLE[0] and BC_PENTIUM_MODE[0].

Table 4–43shows the four combinations of Bcache control pin behavior obtained using the two CSRs.

Table 4–43 Programming the Bcache Control Pins

BC_PENTIUM_MODE	BC_BURST_MODE_ENABLE	RAM_TYPE

0	0	RAM_TYPE A
0	1	RAM_TYPE B
1	0	Unsupported
1	1	Unsupported

Table 4–44lists the combination of control pin assertion for

RAM_TYPE A.

Table 4–44 Control Pin Assertion for RAM_TYPE A

TYPE_A

NOP

RA0

RA1

RA2

RA3

NOP

NOP

WA0

WA1

WA2

WA3

NOP

BcLoad_L

H

H

H

H

H

H

H

H

H

H

H

H

BcDataOE_L

H

L

L

L

L

H

H

L

L

L

L

H

BcDataWr_L

H

H

H

H

H

H

H

L

L

L

L

H

BcTagOE_L

H

L

H

H

H

H

H

L

H

H

H

H

BcTagWr_L

H

H

H

H

H

H

H

L

H

H

H

H

21264/EV68A Hardware Reference Manual

Cache and External Interfaces 4–51

Image 139

Compaq EV68A specifications lists the combination of control pin assertion for, BcAddH234, Bcache Control Pins

Contents

Compaq Computer Corporation Shrewsbury, Massachusetts Revision/Update Information 21264/EV68A Hardware Reference Manual Table of Contents Cache and External Interfaces Hardware Interface Internal Processor Registers Privileged Architecture Library Code Mffpcr Mtfpcr Initialization and Configuration Thermal Management Error Detection and Error HandlingTestability and Diagnostics Electrical Data 21264/EV68A Boundary-Scan Register Alpha Instruction Set Glossary Index 21264/EV68A-to-Bcache Pin Interface Figures 10-2 Type 2 Heat Sink Tables Xiv VDD Idcpower Page Preface ContentAudience Documentation Included by Reference For example Terminology and ConventionsAbbreviations Aligned and Unaligned W1CW1S Addresses External Signal NamesData Units Do Not Care Undefined Do not care. a capital X represents any valid value Page Architecture IntroductionIntroduction Floating-Point Data Types ArchitectureAddressing Integer Data Types 21264/EV68A Microprocessor Features 21264/EV68A Microprocessor Features 21264/EV68A Microprocessor Features 21264/EV68A Microarchitecture Internal ArchitectureInternal Architecture 21264/EV68A Microarchitecture Instruction Fetch, Issue, and Retire UnitVirtual Program Counter Logic Branch Predictor 21264/EV68A Block Diagram Global Predictor Local Predictor Instruction-Stream Translation Buffer Choice Predictor Instruction Fetch Logic Integer Issue QueueRegister Rename Maps Hwret Floating-Point Issue Queue Exception and Interrupt Logic Integer Execution UnitRetire Logic Integer Execution Unit-Clusters 0 PERR, MINxxx, MAXxxx, UNPKxx, PKxx 10Internal Architecture Floating-Point Execution Unit Onchip Caches External Cache and System Interface Unit21264/EV68A contains two onchip primary-level caches Data Cache Memory Reference Unit12Internal Architecture Miss address file MAF Dstream translation buffer DTB Pipeline OrganizationPipeline Organization Srom Interface Stage 1 Instruction Slot Stage 0 Instruction Fetch14Internal Architecture Stage 2 Map Stage 3 Issue Ebox and Fbox pipelines begin execution Instruction Issue RulesInstruction Issue Rules Pipeline Aborts Instruction Name, Pipeline, and Types Instruction Group Definitions Instruction Group Definitions and Pipeline Unit Ebox SlottingFTOIS, Ftoit ITOFS, ITOFF, Itoft U U L E L U E E L L E U 20Internal Architecture Instruction LatenciesInstruction Class Latency in Cycles Hwmfpr Instruction Retire Rules Instruction Retire RulesMinimum Retire Latencies for Instruction Classes BSR/JSR Retire of Operate Instructions into R31/F31Retire of Operate Instructions into R31/F31 Floating-Point Divide/Square Root Early Retire Instructions Retired Without Execution Load Instructions to R31 and F31Load Instructions to R31 and F31 Prefetch with Modify Intent LDS Instruction Load Hit Speculation Special Cases of Alpha Instruction ExecutionSpecial Cases of Alpha Instruction Execution Prefetch, Evict Next LDQ and Hwldq Instructions 10 Pipeline Timing for Floating-Point Load Instructions Cmov Instruction Floating-Point Store Instructions26Internal Architecture 2 I/O Address Space Load Instructions Memory and I/O Address Space InstructionsMemory and I/O Address Space Instructions Memory Address Space Load Instructions Rules for I/O Address Space Load Instruction Data Merging Memory Address Space Store Instructions28Internal Architecture Rules for I/O Address Space Store Instruction Data Merging 4 I/O Address Space Store Instructions Instruction Ordering MAF Memory Address Space Merging RulesMAF Memory Address Space Merging Rules Replay Traps Replay TrapsMbox Order Traps Memory Barrier MB/WMB/TB Fill Flow 12 I/O Write Buffer and the WMB InstructionWrite Buffer and the WMB Instruction Other Mbox Replay Traps WMB Instruction Processing MB Instruction Processing 34Internal Architecture TB Fill Flow12 TB Fill Flow Example Sequence 13 TB Fill Flow Example Sequence Floating-point control register Fpcr is shown in Figure Performance Measurement Support-Performance CountersFloating-Point Control Register Performance Measurement Support-Performance Counters 14 Floating-Point Control Register Fields Floating-Point Control Register36Internal Architecture Amask and Implver Instruction Values Amask and Implver Instruction Values Implver Design ExamplesDesign Examples Amask 12 Typical Uniprocessor Configuration Page Hardware Interface 21264/EV68A Microprocessor Logic SymbolHardware Interface 21264/EV68A Microprocessor Logic Symbol 21264/EV68A Microprocessor Logic Symbol 21264/EV68A Signal Descriptions 21264/EV68A Signal Names and Functions21264/EV68A Signal Names and Functions Signal Pin Types Definitions Dcokh Pllvdd TestStatH 21264/EV68A Signal Descriptions by Function SysVref Domain SysAddInL140 Pin Assignments Pin List Sorted by Signal NamePin Assignments AC1 Pllvdd 10Hardware Interface AA5 12Hardware Interface Pin List Sorted by PGA Location SysDataL28 14Hardware Interface BcDataH70 SysDataL5 16Hardware Interface Ground and Power VSS and VDD Pin List Mechanical Specifications Mechanical Specifications 21264/EV68A Packaging 21264/EV68A Packaging18Hardware Interface 21264/EV68A Bottom View Pin Up Page Introduction to the External Interfaces Cache and External InterfacesCache and External Interfaces Introduction to the External Interfaces 21264/EV68A System and Bcache Interfaces System Interface Second-Level Cache Bcache Interface Commands and AddressesPhysical Address Considerations Physical Address Considerations MB/WMB ECB I/O Physical Address Considerations System Duplicate Tag Stores Bcache Interface SignalsBcache Structure Bcache Structure Cache Coherency Basics Victim Data BufferCache Coherency Victim Data Buffer 21264/EV68A-Supported Cache Block States Cache CoherencyCache Block States 2lists the cache block states supported by the 21264/EV68A Cache Block State Transitions Mands. -4lists these commandsSystem Responses to 21264/EV68A Commands Cache Block State Transitions System Responses to 21264/EV68A Commands and Reactions Using SysDc Commands 12Cache and External Interfaces Dcache States and Duplicate Tags Lock Mechanism Lock Mechanism14Cache and External Interfaces Internal Eviction of LDxL Blocks In-Order Processing of LDxL/STxC InstructionsLiveness and Fairness System Port System Port16Cache and External Interfaces System Port Pins System Port Pins 18Cache and External Interfaces Programming the System Interface ClocksProgramming Values for System Interface Clocks Program Values for Data-Sample/Drive CSRs Bank Interleave on Cache Block Boundary Mode 3 21264/EV68A-to-System CommandsForwarded Clocks and Frame Clock Ratio 12describes the field definitions for Tables 4-10and Hit Mode11 Page Hit Mode of Operation 12 21264/EV68A-to-System Command Fields Definitions 13 Maximum Physical Address for Short Bus Format 4 21264/EV68A-to-System Commands Descriptions14describes the 21264/EV68A-to-system commands 14 21264/EV68A-to-System Commands Descriptions 22Cache and External Interfaces 15 Programming INVALTODIRTYENABLE10 24Cache and External Interfaces ProbeResponse Commands Command40 =16 Programming SETDIRTYENABLE20 17 21264/EV68A ProbeResponse Command 18describes the ProbeResponse command fields SysAck and 21264/EV68A-to-System Commands Flow Control18 ProbeResponse Fields Descriptions RVB RPB System-to-21264/EV68A CommandsProbe Commands Four Cycles 19 System-to-21264/EV68A Probe Commands 21 Data Movement Selection by Probe43 20 System-to-21264/EV68A Probe Commands Fields Descriptions21 lists the data movement selected by Probe43 22lists the next cache block state selected by Probe20 23 Data Transfer Command Format Data Transfer Commands Two Cycles28Cache and External Interfaces 24 SysDc40 Field Description 24describes the SysDc40 field 8.1 21264/EV68A Clock Basics Data Movement In and Out of the 21264/EV68A30Cache and External Interfaces Fast Data Mode 32Cache and External Interfaces 25 Sysclk Cycles Between SysAddOut and SysData 26 Cbox CSR SYSDCDELAY40 Examples 26shows four example configurations and shows their useFast Data Disable Mode 34Cache and External Interfaces 27 Four Timing ExamplesSysDataInValidL and SysDataOutValidL SysDataInValidL SysFillValidL SysDataOutValidL 28 Data Wrapping Rules Data Wrapping36Cache and External Interfaces 29 System Wrap and Deliver Data 30defines the interleaved scheme for the wrap order30 Wrap Interleave Order 38Cache and External Interfaces Nonexistent Memory Processing31defines the wrap order for double-pumped data trans fers 31 Wrap Order for Double-Pumped Data Transfers 21264/EV68A Command NXM Address System/21264/EV68A Response Ordering of System Port Transactions 10.1 21264/EV68A Commands and System Probes40Cache and External Interfaces System Port Bcache Port Bcache Port 36 Bcache Port Pins Bcache Port Pins35 Range of Maximum Bcache Clock Ratios 44Cache and External Interfaces Bcache Clocking 38 BCCLKDELAY10 Values 37 BCCPUCLKDELAY10 ValuesSetting the Period of the Cache Clock 46Cache and External Interfaces 39 Program Values to Set the Cache Clock Period Single-Data 41 Data-Sample/Drive Cbox CSRs Bcache TransactionsBcache Data Read and Tag Read Transactions 48Cache and External Interfaces Bcache Data Write Transactions Dual-data mode, bcfrm is twice the ratio When the ratio is even, bcfrm is equal to the ratioWhen the ratio is odd, bcfrm is twice the ratio For example, in single-data mode 50Cache and External Interfaces Pin DescriptionsRelationship Between Write-to-Read Bcwrrdbubbles and wrrd Relationship Between Read-to-Write Bcrdwrbubbles and rdwr BcAddH234 Bcache Control Pins43 Programming the Bcache Control Pins 44 lists the combination of control pin assertion for 52Cache and External Interfaces 45 Control Pin Assertion for Ramtype B46 Control Pin Assertion for Ramtype C 47 Control Pin Assertion for Ramtype D Disabling the Bcache for Debugging Bcache BankingBcDataInClkH and BcTagInClkH Interrupts Interrupts54Cache and External Interfaces Internal Processor Registers Internal Processor Registers Mbox IPRs Cycle Counter Control Register Ccctl Ebox IPRsEbox IPRs Cycle Counter Register CC Cycle Counter Control Register Fields Description Virtual Address Register VAVirtual Address Control Register Vactl 2describes the Ccctl register fields VAFORM32 Virtual Address Format Register Vaform3describes the virtual address control register fields Virtual Address Control Register Fields Description ITB PTE Array Write Register Itbpte Ibox IPRsIbox IPRs ITB Tag Array Write Register Itbtag ITB Invalidate All Register Itbia ITB Invalidate All Process ASM=0 Register ItbiapITB Invalidate Single Register Itbis ProfileMe PC Fields Description ProfileMe PC Register PmpcException Address Register Excaddr 4describes the ProfileMe PC register fields Instruction Virtual Address Format Register Ivaform Interrupt Enable and Current Processor Mode Register Iercm Iercm Register Fields Description Software Interrupt Request Register Sirr10Internal Processor Registers 6describes the software interrupt request register fields Interrupt Summary Register IsumSoftware Interrupt Request Register Fields Description 12Internal Processor Registers Hardware Interrupt Clear Register Hwintclr7describes the interrupt summary register fields Interrupt Summary Register Fields Description Mchkd W1C Exception Summary Register Excsum8describes the hardware interrupt clear register fields Hardware Interrupt Clear Register Fields Description Exception Summary Register Fields Description 9describes the exception summary register fields14Internal Processor Registers 10 PAL Base Register Fields Description PAL Base Register PalbaseIbox Control Register Ictl 10describes the PAL base register fields 11 Ibox Control Register Fields Description 11describes the Ibox control register fields16Internal Processor Registers PCT0EN SingleissuehSTWAIT64K PCT1EN Spce Ibox Status Register Istat18Internal Processor Registers TRP 12describes the Ibox status register fields12 Ibox Status Register Fields Description MIS 20Internal Processor Registers Clear Virtual-to-Physical Map Register Clrmap Sleep Mode Register SleepIcache Flush Register Icflush Icache Flush ASM Register Icflushasm 14 Process Context Register Fields Description 14describes the process context register fields22Internal Processor Registers 15describes the performance counter control register fields Performance Counter Control Register Pctrctl15 Performance Counter Control Register Fields Description SL0 PctxppcePmstalled Pmkilledbm 16 Performance Counter Control Register Input Select Fields Mbox IPRsMbox IPRs DTB Tag Array Write Registers 0 and 1 DTBTAG0, DTBTAG1 17describes the Dtbaltmode register fields DTB Alternate Processor Mode Register Dtbaltmode17 DTB Alternate Processor Mode Register Fields Description DTB PTE Array Write Registers 0 and 1 DTBPTE0, DTBPTE1 ALTMODE10 Dstream TB Invalidate All Process ASM=0 Register DtbiapDstream TB Invalidate All Register Dtbia Dstream TB Invalidate Single Registers 0 and 1 DTBIS0,1 18 Memory Management Status Register Fields Description Dstream TB Address Space Number Registers 0 and 1 DTBASN0,1Memory Management Status Register Mmstat 18describes the memory management status register fields For Mbox Control Register MctlACV 19 Mbox Control Register Fields Description Erences to superpages result in access violationsDcache Control Register Dcctl 19describes the Mbox control register fields 20describes the Dcache control register fields Dcache Status Register Dcstat20 Dcache Control Register Fields Description 21 Dcache Status Register Fields Description Cbox CSRs and IPRsCbox CSRs and IPRs 21describes the Dcache status register fields 22 describes the Cbox data register fields Cbox Data Register CdataCbox Shift Register Cshft Cbox Writeonce Chain Description 34Internal Processor Registers 24 Cbox Writeonce Chain Order Mboxbcprbstall BCLATDATAPATTERN031 BCLATTAGPATTERN023 BCWRRDBUBBLES03 36Internal Processor Registers SYSCLKDELAY10 38Internal Processor Registers Cbox Writemany Chain Description 25 Cbox Writemany Chain Order 40Internal Processor Registers 26 Cbox Read IPR Fields Description Cbox Read Register IPR Description 0 1 1 Istreammemerr 0 1 1 Dstreammemerr PALcode Description Privileged Architecture Library CodePrivileged Architecture Library Code PALmode Environment PALmode Environment Hwld Instruction Required PALcode Function CodesOpcodes Reserved for PALcode Required PALcode Function Codes Hwld Instruction Fields Descriptions Opcodes Reserved for PALcodeHwst Instruction 3describes the Hwld instruction fields 4describes the Hwst instruction fields Hwret InstructionHwst Instruction Fields Descriptions Hint Hwmfpr and Hwmtpr Instructions5describes the Hwret instruction fields Hwret Instruction Fields Descriptions Hwmfpr and Hwmtpr Instructions Fields Descriptions Internal Processor Register Access MechanismsInternal Processor Register Access Mechanisms 6describes the Hwmfpr and Hwmtpr instructions fields Hardware Structure of Explicitly Written IPRs IPR Scoreboard Bits Hardware Structure of Implicitly Written IPRs IPR Access OrderingPaired Instruction Fetch Order 10Privileged Architecture Library Code PALcode Emulation of the Fpcr PALshadow RegistersPALshadow Registers PALcode Entry Points PALcode Entry Points PALcode Exception Entry Locations PALcode Exception Entry Points 14Privileged Architecture Library Code Translation Buffer TB Fill FlowsTranslation Buffer TB Fill Flows DTB Fill Tb miss Wr DataWr PTE LD-PTE, write TB 16Privileged Architecture Library Code ITB Fill Performance Counter Support Performance Counter Support IPRs Used for Performance Counter Support General PrecautionsAggregate Mode Programming Guidelines Aggregate Mode Precautions SL1 10 Aggregate Mode Returned IPR ContentsOperation Pctrctl SL0 11shows the counter modes that are used with Aggregate mode ProfileMe Mode Programming GuidelinesThis input counts Mbox replay traps 12 Cmov Decomposed 22Privileged Architecture Library Code 13 ProfileMe Mode Returned IPR Contents Inum retire delay cycles ProfileMe Counting Mode Description Cycle counting 24Privileged Architecture Library Code 14shows the counter modes that are used with ProfileMe modeCounter Modes for ProfileMe Mode 14 ProfileMe Mode Pctrctl Input Select Fields Initialization and Configuration Initialization and ConfigurationPower-Up Reset Flow and the ResetL and Dcokh Pins 21264/EV68A Reset State Machine Major Operations Constraints Power-Up Reset Flow and the ResetL and Dcokh Pins Signal Pin Reset State Power Sequencing and Reset State for Signal Pins Pllvdd Clock Forwarding and System Clock Ratio Configuration PLL Pin Signal Names and Initialization State BiST and Srom Load and the TestStatH Pin PLL Ramp Up Power-Up Flow Signals and Their Constraints Clock Forward Reset and System Interface InitializationEV68A Fault Reset Flow Fault Reset FlowEffect on IPRs After Fault Reset Energy Star Certification and Sleep Mode Flow Energy Star Certification and Sleep Mode Flow 10Initialization and Configuration Effect on IPRs After Transition Through Sleep Mode Effect on IPRs After Warm Reset Warm Reset FlowWarm Reset Flow Signals and Constraints for the Sleep Mode Sequence Array Initialization Initialization Mode Processing12Initialization and Configuration Array Initialization Evictenable BCWRTSTS30 Bcbankenable Initialization Mode Processing External Interface Initialization Internal Processor Register Power-Up Reset State10 Internal Processor Registers at Power-Up Reset State 14Initialization and Configuration Internal Processor Register Power-Up Reset State 16Initialization and Configuration Ieee 1149.1 Test Port ResetReset State Machine Ieee 1149.1 Test Port Reset 11 21264/EV68A Reset State Machine State Descriptions Reset State Machine 18Initialization and Configuration PLL Output Clocks Phase-Lock Loop PLL Functional DescriptionPhase-Lock Loop PLL Functional Description Differential Reference Clocks 20Initialization and Configuration Power-Up/Reset Clocking 21264/EV68A Error Detection Mechanisms Error Detection and Error HandlingError Detection and Error Handling Data Error Correction Code Data Error Correction CodeIcache Data or Tag Parity Error Dcache Tag Parity Error Dcache Data Single-Bit Correctable ECC Error Dcache Data Single-Bit Correctable ECC ErrorLoad Instruction Store Instruction Quadword or Smaller Dcache Store Second ErrorDcache Duplicate Tag Parity Error Dcache Store Second Error Controlling Bcache Block Parity Calculation Bcache Tag Parity ErrorBcache Data Single-Bit Correctable ECC Error Bcache Tag Parity Error Dcache Fill from Bcache Bcache Data Single-Bit Correctable ECC Error Icache Fill from Memory Memory/System Port Single-Bit Data Correctable ECC ErrorMemory/System Port Single-Bit Data Correctable ECC Error Bcache Victim Read Dcache Fill from Memory Double-Bit Fill Errors Bcache Data Single-Bit Correctable ECC Error on a ProbeBcache Data Single-Bit Correctable ECC Error on a Probe Section D.36 Error Case SummaryError Case Summary 3summarizes the various error cases and their ramifications Mchk Cstatistreambcdbl Mchk CstatistreammemerrCstatdstreammemerr CRD CstatprobebcerrPage Maximum Electrical Ratings Electrical CharacteristicsElectrical Data 1lists the maximum electrical ratings for the 21264/EV68A Idcpower DC CharacteristicsDC Characteristics Signal Types Input Differential Amplifier Clock Receiver Idaclk VDD IdcpowerInput DC Reference Pin Idcref Input Differential Amplifier Receiver IDA Codtp Pin Type Open-Drain Driver for Test Pins OodtpPin Type Open-Drain Output Driver OOD IOZ 12 Push-Pull Output Clock Driver Oppclk 11 Push-Pull Output Driver OPP AC Characteristics AC CharacteristicsAC Test Conditions TSU1 TDH2 13 AC Specifications Dcokh AC Characteristics Page That causes thermal failure Operating TemperatureOperating Temperature at Heat Sink Center Tc Thermal Management Θca at Various Airflows for 21264/EV68A Operating Temperature10-2Thermal Management Heat Sink Specifications Heat Sink Specifications 10-4Thermal Management Type 2 Heat Sink Type 3 Heat Sink Thermal Design Considerations Thermal Design Considerations10-6Thermal Management Testability and Diagnostics Testability and DiagnosticsTest Pins Dedicated Test Port Pins Srom Load Operation SROM/Serial Diagnostic Terminal PortSROM/Serial Diagnostic Terminal Port 11-2Testability and Diagnostics Ieee 1149.1 Port Ieee 1149.1 PortIeee 1149.1 Instructions and Opcodes TAP Controller State Machine 11-4Testability and DiagnosticsTestStatH Pin TestStatH Pin Srom Initialization Power-Up Self-Test and InitializationPower-Up Self-Test and Initialization Built-in Self-Test Serial Instruction Cache Load Operation 11-6Testability and Diagnostics Icache Bit Fields in an Srom Line See Appendix B for a listing of the Boundary-Scan RegisterReferences Page Alpha Instruction Set A-1 Alpha Instruction SetAlpha Instruction Summary Table A-1 Instruction Format and Opcode Notation Alpha Instruction Summary Opr 11.46 Cmove if ≥ zero Mbr Branch to subroutinePcd Trap to PALcode Opr 11.24 Cmove if = zero 15.0BE Convert quadword to Gfloating 15.0AF Convert Gfloating to quadword17.010 Convert longword to quadword 15.0BC Convert quadword to Ffloating 17.02B Fcmove if ≠ zero 17.02F Fcmove if zero17.02E Fcmove if ≤ zero 17.02C Fcmove if zero Mem Load Sfloating Opr 13.40 Multiply longword with integer overflow enableOpr 13.60 Multiply quadword with integer overflow enable Opr 1C.31 Pixel error Opr 10.02 Scaled add longword by Opr 1C.36 Pack words to bytes Mfc 18.E000 Read and clearMbr 1A.2 Return from subroutine Mfc 18.C000 Read process cycle counter 18.F000 Read and set Reserved Opcodes Reserved OpcodesOpcodes Reserved for Compaq Ieee Floating-Point Instructions Ieee Floating-Point InstructionsOpcodes Reserved for PALcode 12B 16B 08B 00B 04B18B 10B 14B 02B 06B Independent Floating-Point Instructions VAX Floating-Point InstructionsVAX Floating-Point Instructions Opcode Summary Opcode Summary Floating-point operate instruction opcodes Mem Table A-9explains the symbols used in Table A-8Mem Res Ieee floating-point instruction opcodes Ieee Floating-Point Conformance Ieee Floating-Point Conformance14Alpha Instruction Set Alpha Instruction Set A-15 Table A-11 Exceptional Input and Output Conditions 16Alpha Instruction Set Cmptlt Cmptle Input Cmpteq Cmptun InputAlpha Instruction Set A-17 Fbeq Fbne Fblt Fble Fbgt Fbge LDS LDT STS STT Cpys Cpysn Boundary-Scan Register 21264/EV68A Boundary-Scan Register Pllvdd Boundary-Scan Register 21264/EV68A Boundary-Scan Register B-3 421264/EV68A Boundary-Scan Register 21264/EV68A Boundary-Scan Register B-5 621264/EV68A Boundary-Scan Register 21264/EV68A Boundary-Scan Register B-7 821264/EV68A Boundary-Scan Register 21264/EV68A Boundary-Scan Register B-9 1021264/EV68A Boundary-Scan Register 21264/EV68A Boundary-Scan Register B-11 1221264/EV68A Boundary-Scan Register Serial Icache Load Predecode Values C-1 Serial Icache Load Predecode ValuesPage PALcode Restrictions and Guidelines D-1 PALcode Restrictions and Guidelines 2PALcode Restrictions and Guidelines PALcode Restrictions and Guidelines D-3 4PALcode Restrictions and Guidelines Initwritemany PALcode Restrictions and Guidelines D-5 6PALcode Restrictions and Guidelines PALcode Restrictions and Guidelines D-7 8PALcode Restrictions and Guidelines PALcode Restrictions and Guidelines D-9 Restriction 7 Replay Trap, Interrupt Code Sequence, and STF 10PALcode Restrictions and Guidelines Restriction 10 Duplicate IPR Mode BitsRestriction 9 PALmode Istream Address Ranges Restriction 9 PALmode Istream Address Ranges Restriction 14 Hwret Restriction 11 Ibox IPR Update SynchronizationRestriction 11 Ibox IPR Update Synchronization Restriction 13 DTB Fill Flow Collision Guideline 16 JSR-BAD VA Guideline 20 Ictlsbe Stream Buffer EnableGuideline 16 JSR-BAD VA Restriction 21 HWRET/STALL After Hwmtpr ASN0/ASN1 Restriction 22 HWRET/STALL After Hwmtpr IS0/IS1 Restriction 22 HWRET/STALL After Hwmtpr IS0/IS1PALcode Restrictions and Guidelines D-13 14PALcode Restrictions and Guidelines Restriction 25 Hwmtpr Itbia After ResetGuideline 26 Conditional Branches in PALcode Restriction 24 HWRET/STALL After Hwmtpr ICFLUSH, Icflushasm Restriction 30 Hwmtpr and Hwmfpr to the Cbox CSR Guideline 29 JSR, JMP, RET, and Jsrcor in PALcodePALcode Restrictions and Guidelines D-15 16PALcode Restrictions and Guidelines Restriction 30 Hwmtpr and Hwmfpr to the Cbox CSR PALcode Restrictions and Guidelines D-17 Restriction 31 ICTLVA48 UpdateRestriction 32 Pctrctl Update Restriction 31 ICTLVA48 Update Restriction 37 Updating VACTLVA48 Guideline 35 Hwintclr UpdateRestriction 33 Hwld Physical/Lock Use Restriction 36 Updating Ictlsde PALcode Restrictions and Guidelines D-19 Restriction 40 Scrubbing a Single-Bit Error 20PALcode Restrictions and Guidelines Restriction 40 Scrubbing a Single-Bit Error Restriction 43 No Trappable Instructions Along with Restriction 42 Updating VACTL, CCCTL, or CC IPRsPALcode Restrictions and Guidelines D-21 22PALcode Restrictions and Guidelines Restriction 47 Cache Eviction for Single-Bit Cache Errors PALcode Restrictions and Guidelines D-23 Restriction 47 Cache Eviction for Single-Bit Cache Errors 24PALcode Restrictions and Guidelines Forwarding Clock Pin Groupings 21264/EV68A-to-Bcache Pin InterfaceTable E-1 Bcache Forwarding Clock Pin Groupings Tag Pin Usage Late-Write Non-Bursting SSRAMsLate-Write Non-Bursting SSRAMs Data Pin Usage Dual-Data Rate SSRAMs Dual-Data Rate SSRAMsTable E-4 Dual-Data Rate Ssram Data Pin Usage Table E-5 Dual-Data Rate Ssram Tag Pin Usage Trstl421264/EV68A-to-Bcache Pin Interface 21264/EV68A-to-Bcache Pin Interface E-5 Page Glossary BIU BSR Cisc CSR CmosCPI CPU DTL DMADram DTB Fpga FepromFET FEU IDU Gclk Jfet IowbIpga ITB Mips MAFMBO MBZ Nvram MSINaturally Aligned Nmos Plcc PALPGA PLA RAS PqfpProm RAM SAM RiscROM RTL Sipp SdramSimm SIP Unaligned StramTTL Uart VDF UnpredictableUvprom VAF Writeblock WAR Numerics Index Index-2 Index-3 Index-4 ECC Index-6 Index-7 Index-8 Index-9 Index-10 Index-11 Index-12