RDN+1 | Intel PXA255 guide

Memory Controller

Figure 6-18. Eight-Beat Burst Read from 16-Bit Burst-of-Four ROM or Flash (MSC0[RDF] = 4, MSC0[RDN] = 1, MSC0[RRR] = 0)

0ns	50ns		100ns			150ns	200ns	250ns
CLK_MEM
nCS[0]
	tAS
MA[25:5]
	RDF+2		RDN+1
MA[4:2]	0	1	2	3	4	5	6	7
MA[1:0]				"00"
	RDF+1							RRR*2+1
nADV(nSDCAS)
	tCES							tCEH
nOE
nWE
RDnWR
		tDOH
		tDSOH
MD[31:0]
DQM[3:0]			"0000"

nCS[1]

*MSC0:RDF0 = 4, RDN0 = 1, RRR0 = 1 tAS = Address Setup to nCS asserted = 1 clk_mem tCES = nCS setup to nOE asserted = 0 ns

tCEH = nCS hold from nOE deasserted = 0 ns

tDSOH = MD setup to Address changing = 1.5 clk_mems plus board routing delays

tDOH = MD hold from Address changing = 0 ns

6-52	Intel® PXA255 Processor Developer’s Manual

Image 234

Intel PXA255 manual RDN+1

Contents

Intel PXA255 Processor Intel PXA255 Processor Developer’s Manual Contents Power Manager General Configuration Register Pcfr Contents Expansion Card Interface Timing Diagrams and Parameters DMA 10-1 11-1 12.6 14.3 15.5 Figures BitBurst-of-Eight ROM or Flash Read Timing Diagram MSC0RDF = 10-25 Tables Clocks Manager Register Summary Sxcnfg 10-6 10-8 12-26 15-7 Revision History Date Revision Description Xxiv Intel XScale Microarchitecture Features System Integration Features Clocks and Power Controllers Memory ControllerUniversal Serial Bus USB Client 6 AC97 Controller DMA Controller DmacLCD Controller Inter-IC Sound I2S Controller Gpio Synchronous Serial Protocol Controller SspcInter-Integrated Circuit I2C Bus Interface Unit UARTs Pulse-Width Modulator PWM OS TimersReal-Time Clock RTC Interrupt Control Introduction System Architecture Overview Intel XScale Microarchitecture Implementation Options Coprocessor 7 Register 4 Psfs Bit Coprocessor 14 Registers 0-3 Performance Monitoring Coprocessor 14 Register 6 and 7- Clock and Power ManagementCPU Core Fault Register Bit Definitions Coprocessor 15 Register 0 ID Register Definition PXA255 Processor ID Values Coprocessor 15 Register 1 P-BitID Bit Definitions ARM ID Jtag ID I/O Ordering SemaphoresInterrupts USB ResetUnit Sleep Mode Gpio Reset Watchdog Reset Hard Reset ICP Internal Registers Selecting Peripherals vs. General Purpose I/O Pin List Power on Reset and Boot OperationPower Management Processor Pin Types Pin & Signal Descriptions for the PXA255 Processor Sheet 1 Pin Name Type Signal Descriptions Reset State Sleep State Pin & Signal Descriptions for the PXA255 Processor Sheet 2 Pin & Signal Descriptions for the PXA255 Processor Sheet 3 Psktsel Pin & Signal Descriptions for the PXA255 Processor Sheet 4 Pin & Signal Descriptions for the PXA255 Processor Sheet 5 Pin & Signal Descriptions for the PXA255 Processor Sheet 6 Pin & Signal Descriptions for the PXA255 Processor Sheet 7 Rtcclk Icocz Pin & Signal Descriptions for the PXA255 Processor Sheet 8Bootsel Pwren Pin & Signal Descriptions for the PXA255 Processor Sheet 9 Pin Description Notes Sheet 1 Memory Map Pin Description Notes Sheet 2 Memory Map Part One From 0x80000000 to 0xFFFF Ffff Memory Map Part Two From 0x00000000 to 0x7FFF Ffff Unit Address Register Symbol Register Description System Architecture Register SummarySystem Architecture Register Address Summary Sheet 1 System Architecture Register Address Summary Sheet 2 System Architecture Register Address Summary Sheet 3 System Architecture Register Address Summary Sheet 4 System Architecture Register Address Summary Sheet 5 Unit System Architecture Register Address Summary Sheet 6 System Architecture Register Address Summary Sheet 7 Unit Address System Architecture Register Address Summary Sheet 8 System Architecture Register Address Summary Sheet 9 System Architecture Register Address Summary Sheet 10 System Architecture Register Address Summary Sheet 11 System Architecture Register Address Summary Sheet 12 Clocks and Power Manager Clock Manager Introduction Power Manager Introduction Clock Manager OST Retains Power in SleepPWM SSP Ficp I2C MMC Core Phase Locked Loop 1 32.768 kHz Oscillator2 3.6864 MHz Oscillator Core PLL Output Frequencies for 3.6864 MHz Crystal 4 95.85 MHz Peripheral Phase Locked Loop5 147.46 MHz Peripheral Phase Locked Loop Sdram Resets and Power Modes Hardware ResetClock Gating Watchdog Reset Invoking Gpio Reset Gpio ResetCompleting a Watchdog Reset Behavior During Gpio Reset Completing Gpio Reset Run ModeTurbo Mode Entering Turbo Mode Exiting Turbo Mode Idle ModeBehavior in Turbo Mode Entering Idle Mode Frequency Change Sequence Behavior in Idle ModeExiting Idle Mode Preparing for a Frequency Change Sequence Invoking the Frequency Change Sequence Behavior During the Frequency Change Sequence 8 33-MHz Idle Mode Completing the Frequency Change Sequence Entering 33-MHz Idle Mode Behavior in 33-MHz Idle Mode Sleep Mode Exiting 33-MHz Idle ModeSleep Mode External Voltage Regulator Requirements Preparing for Sleep Mode Entering Sleep Mode Clocks and Power Manager Behavior in Sleep Mode Exiting Sleep Mode Clocks and Power Manager Power Mode Exit Sequence Table Sheet 1 Power Mode SummaryPower Mode Entry Sequence Table Idle Power Mode Exit Sequence Table Sheet 2 Power Manager Registers Power Mode Supply Source Module Turbo Run Pmcr Power Manager Control Register PmcrPmcr Bit Definitions Idae Pcfr Power Manager General Configuration Register PcfrPcfr Bit Definitions Opde Wertc Power Manager Wake-Up Enable Register PwerPwer Bit Definitions Pwer 0x40F00010 Power Manager Rising-Edge Detect Enable Register Prer10. Prer Bit Definitions Prer 0x40F00014 Power Manager Falling-Edge Detect Enable Register Pfer11. Pfer Bit Definitions Pfer 0x40F00018 Power Manager Gpio Edge Detect Status Register Pedr12. Pedr Bit Definitions Pedr Pssr Power Manager Sleep Status Register Pssr13. Pssr Bit Definitions Sheet 1 RDH 14. Pspr Bit Definitions Power Manager Scratch Pad Register Pspr13. Pssr Bit Definitions Sheet 2 CPU VFS Power Manager Fast Sleep Walk-up Configuration Register Pmfw 15. Pmfw Register Bitmap and Bit Definitions PGSR0 16. PGSR0 Bit Definitions17. PGSR1 Bit Definitions SS9 SS8 SS7 SS6 SS5 SS4 SS3 SS2 SS1 SS0 18. PGSR2 Bit Definitions Reset Controller Status Register RcsrBit Reset 0x40F00028 PGSR2 19. Rcsr Bit Definitions Core Clock Configuration Register CccrClocks Manager Registers Rcsr Bit Reserved 20. Cccr Bit Definitions0x41300000 Multiplier = Clock Enable Register Cken 21. Cken Bit Definitions Sheet 1 CKEN8 Description I2S Unit Clock Enable21. Cken Bit Definitions Sheet 2 CKEN5 Coprocessor 14 Clock and Power Management Oscillator Configuration Register Oscc22. Oscc Bit Definitions Core Clock Configuration Register Cclkcfg 23. Coprocessor 14 Clock and Power Management Summary24. Cclkcfg Bit Definitions Power Supply Connectivity Power Mode Register PwrmodePower-On-Reset Considerations External Hardware Considerations Power Manager Register Summary Clocks and Power Manager Register SummaryDriving the Crystal Pins from an External Clock Source Clocks Manager Register Locations 27. Power Manager Register Summary General-Purpose I/O Gpio Operation General-Purpose I/O Block Diagram Gpio Alternate Functions Gpio Alternate Functions Sheet 1 Gpio Alternate Functions Sheet 2 Gpio Alternate Functions Sheet 3 MMCCS0 ALTFN1OUTMbgnt ALTFN1OUT Gpio Register Definitions Gpio Alternate Functions Sheet 4Gpio Register Definitions Sheet 1 GPLR0 Bit Definitions Gpio Pin-Level Registers GPLR0, GPLR1, GPLR2Gpio Register Definitions Sheet 2 GPLR0 GPLR2 Bit Definitions Gpio Pin Direction Registers GPDR0, GPDR1, GPDR2GPLR1 Bit Definitions GPLR1 GPDR0 Bit Definitions GPDR1 Bit DefinitionsGPDR2 Bit Definitions GPSR0 GPSR0 Bit Definitions10. GPSR1 Bit Definitions PS9 PS8 PS7 PS6 PS5 PS4 PS3 PS2 PS1 PS0 11. GPSR2 Bit Definitions 12. GPCR0 Bit Definitions13. GPCR1 Bit Definitions GPCR2 Bit Definitions GPCR2 15. GRER0 Bit Definitions 16. GRER1 Bit Definitions17. GRER2 Bit Definitions 18. GFER0 Bit Definitions 19. GFER1 Bit DefinitionsGFER2 Bit Definitions Gpio Edge Detect Status Register GEDR0, GEDR1, GEDR2 21. GEDR0 Bit Definitions22. GEDR1 Bit Definitions GEDR2 Bit Definitions GEDR2 GAFR0L 24. GAFR0L Bit Definitions25. GAFR0U Bit Definitions AF9 AF8 AF7 AF6 AF5 AF4 AF3 AF2 AF1 AF0 GAFR1L 26. GAFR1L Bit Definitions27. GAFR1U Bit Definitions GAFR1U GAFR2L 28. GAFR2L Bit Definitions29. GAFR2U Bit Definitions GAFR2U Interrupt Controller Interrupt Controller Operation Interrupt Controller Block Diagram Interrupt Controller Register Definitions 30. Icmr Bit Definitions Interrupt Controller Mask Register IcmrInterrupt Controller Level Register Iclr Icmr Interrupt Controller Control Register Iccr 31. Iclr Bit Definitions32. Iccr Bit Definitions 33. Icip Bit Definitions 34. Icfp Bit Definitions Icpr Interrupt Controller Pending Register Icpr35. Icpr Bit Definitions Sheet 1 IS9 IS8 IS14 IS13 IS12 IS11 IS10 Network SSP Service Request Interrupt Pending35. Icpr Bit Definitions Sheet 2 IS16 System Integration Unit 35. Icpr Bit Definitions Sheet 336. List of First-Level Interrupts Sheet 1 Bit Position Source Unit Real-Time Clock RTC Real-Time Clock Operation36. List of First-Level Interrupts Sheet 2 RTC Register Definitions RTC Trim Register Rttr RTC Alarm Register Rtar Rttr Bit Definitions38. Rtar Bit Definitions 39. Rcnr Bit Definitions RTC Counter Register RcnrRTC Status Register Rtsr Rcnr Trim Procedure Oscillator Frequency Calibration40. Rtsr Bit Definitions Rttr Value Calculations Trim Example #1 Measured Value Has No Fractional ComponentTrim Example #2 Measured Value Has a Fractional Component Operating System OS Timer Maximum Error Calculation Versus RTC Accuracy Watchdog Timer Operation OS Timer Register DefinitionsOS Timer Match Register 0-3 OSMRx 42. Oier Bit Definitions OS Timer Interrupt Enable Register Oier41. OSMRx Bit Definitions OSMR3, OSMR2, OSMR1 OS Timer Status Register Ossr OS Timer Watchdog Match Enable Register OwerOS Timer Count Register Oscr 43. Ower Bit Definitions Pulse Width Modulator Operation 0x40A00014 Bit Reset ? ? ? ? ? ? ? ? BitsPulse Width Modulator Ossr Bit Definitions PWMn Block Diagram 1.1 Interdependencies Register Descriptions Reset SequencePower Management Requirements PWM Control Registers PWMCTRLn 0x40B00000 PWM Duty Cycle Registers PWMDUTYn46. PWMCTRLn Bit Definitions Prescale PWMDUTY0, PWMDUTY1 PWM Period Control Register PWMPERVALn47. PWMDUTYn Bit Definitions Fdcycle Dcycle Pulse Width Modulator Output Wave Example 48. PWMPERVALn Bit Definitions0x40B00008 System Integration Unit Register Summary Gpio Register Locations49. Gpio Register Addresses Sheet 1 OS Timer Register Locations Interrupt Controller Register LocationsReal-Time Clock Register Locations 52. OS Timer Register Addresses Sheet 2 Pulse Width Modulator Register Locations53. Pulse Width Modulator Register Addresses Dmac Block Diagram DMA Description Dmac Signal List Signal DescriptionsDREQ10 and PREQ370 Signals Signal Signal Type To/From Definition In/Out Dmairq Signal DMA Channel Priority Scheme Channel Priority if all channels are running concurrently Channel Priority Priority Schemes Examples No-Descriptor Fetch ModeDMA Descriptors DMA Channel Priority Descriptor Fetch Mode No-Descriptor Fetch Mode Channel State DMA Controller Channel States Servicing an Interrupt Read and Write Order Byte Transfer Order Trailing Bytes Little Endian Transfers Transferring Data Servicing Internal Peripherals Dcmdincsrcaddr = Dcmdflowsrc = Dcmdflowtrg = Dcmd Quick Reference for DMA ProgrammingDMA Quick Reference for Internal Peripherals Sheet 1 Drcmr Unit Function Fifo Address Width Servicing Companion Chips and External PeripheralsDMA Quick Reference for Internal Peripherals Sheet 2 Burst Size Source DMA Controller Memory-to-Memory Moves DMA Channel Control/Status Register DCSRx Dmac RegistersDMA Interrupt Register Dint Dint Bit Definitions Reqpend DCSRx Bit Definitions Sheet 1RUN Stopstate Endintr Startintr Buserrintr Reset 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 DCSRx Bit Definitions Sheet 2 DRCMRx Bit Definitions DMA Request to Channel Map Registers DRCMRxDMA Descriptor Address Registers DDADRx Chlnum Descriptor Address DMA Source Address RegistersDDADRx Bit Definitions Stop Source Address DMA Target Address Registers DTADRx10. DSADRx Bit Definitions Srcaddr Target Address DMA Command Registers DCMDx11. DTADRx Bit Definitions Trgaddr Endian Width 12. DCMDx Bit Definitions Sheet 1Incsrcaddr Size Width 12. DCMDx Bit Definitions Sheet 2Endian Length Example 1. How to set up and start a channel Examples Struct longddadr longdsadr longdtadr shortlength shortdcmd DMA Controller Register Summary 13. DMA Controller Register Summary Sheet 1 13. DMA Controller Register Summary Sheet 2 13. DMA Controller Register Summary Sheet 3 13. DMA Controller Register Summary Sheet 4 13. DMA Controller Register Summary Sheet 5 Memory Controller Functional Description Sdram Interface Overview Static Memory Interface / Variable Latency I/O Interface Memory System Examples 3 16-Bit PC Card / Compact Flash Interface Sdram Memory System Example Static Memory System Example Bus Operation Burst Size Memory AccessesDevice Transactions Words Bits Aborts and Nonexistent Memory Synchronous Dram Memory InterfaceReads and Writes Sdram Mdcnfg Register Mdcnfg Mdcnfg Bit Definitions Sheet 1 Mdcnfg Bit Definitions Sheet 2 DADDR2 Mdcnfg Bit Definitions Sheet 3DNB2 DLATCH2 Sdram Mode Register Set Configuration Register Mdmrs Mdmrs Bit Definitions Sheet 1 Low-Power Sdram Mode Register Set Configuration Register Mdmrs Bit Definitions Sheet 2 0X4800 Sdram Mdrefr Register MdrefrMdmrslp Register Bit Definitions Mdmrslp APD K2DB2 K2RUN K1DB2 K1RUN E1PIN K0DB2 K0RUN E0PIN Mdrefr Bit Definitions Sheet 1Mdrefr DRI Mdrefr Bit Definitions Sheet 2 0 1 0 0 1 * * 11 1 1 1 1 1 1 Fixed-Delay or Return-Clock Data Latching Mdrefr Bit Definitions Sheet 3APD Sample Sdram Memory Size Options Sdram Memory OptionsSdram Addressing Modes Number Chips Partition Size # Bits ‘0’1x12x8x32 ‘0’ 1x12x8x16 1x12x9x32 1x12x9x16 1x12x10x32 MA2410 Col Data 2x13x10x16 ‘0’ # Bits External Address pins at Sdram RAS Time Not Valid illegal addressing combination BA0 MA24 MA23MA20 A10 MA24 BA1 BA0 A11 A10 Memory Controller Sdram Command Overview A12 11. Sdram Command Encoding 12. Sdram Mode Register Opcode TableSdram Waveforms Sdclk Data SDRAMreadsamebankdiffrow SDRAMwrite SDCLK1 SDCKE1 Synchronous Static Memory Configuration Register Sxcnfg Synchronous Static Memory Interface Sxcnfg 13. Sxcnfg Bit Definitions Sheet 10x4800001C SXLATCH2 SXTP2 SXCA2 SXRA2 SXRL2 SXCL2 SXEN2 SXRL2 SXCL2 SXEN2 Sxcnfg Bit Definitions Sheet 2SXLATCH2 SXLATCH0 13. Sxcnfg Bit Definitions Sheet 3 SXCL0 Smrom Memory OptionsSxcnfg Bit Definitions Sheet 4 SXEN0 Smrom Sxmrs Synchronous Static Memory Timing Diagrams16. Sxmrs Bit Definitions SXMRS2 Non-SDRAM Timing Sxmem Operation Sdclk Sdcke 17. Read Configuration Register Programming Values Memclk SDCLK0 Mdrefr Non-SDRAM Timing Flash Read Timing Diagram 12shows the burst-of-eight read timing diagram 4.2 K3 Synchronous StrataFlash Reset Asynchronous Static MemoryStatic Memory Interface Sram Data Size MA10 DQM30 19 -Bit Bus Write Access20 -Bit Bus Write Access Data Size MA0 DQM10 21 -Bit Byte Address Bits MA10 for Reads Based on DQM30 22 -Bit Byte Address Bit MA0 for Reads Based on DQM1023. SA-1111 Register Bit Definitions Asynchronous Static Memory Control Registers MSCx MSC1 24. MSC0/1/2 Bit Definitions Sheet 1MSC0 MSC2 RRR1/3/5 RDN1/3/5 Reset RDF1/3/5 Bits Access Name24. MSC0/1/2 Bit Definitions Sheet 2 24. MSC0/1/2 Bit Definitions Sheet 3 Sram NOE ROM InterfaceTiming Memory Clocks MSCxRTx Device NWE NOE ROM Timing Diagrams and Parameters Clkmem RDN+1 Sram Timing Diagrams and Parameters Sram Interface Overview 20shows the timing for Sram writes Variable Latency I/O Vlio Interface Overview Variable Latency I/O Timing Diagrams and Parameters RDF+1+Waits RRR*2+1 RDF+1+Waits Flash Memory Timing Diagrams and Parameters Flash Memory Interface 23. Asynchronous 32-Bit Flash Write Timing Diagram 2 Writes CMD Data 26. MCMEM0/1 Bit Definitions Expansion Memory Timing Configuration Register16-Bit PC Card/Compact Flash Interface MCMEM0 MCATT0 27. MCATT0/1 Bit Definitions28. MCIO0/1 Bit Definitions MCATT1 29. Card Interface Command Assertion Code Table MCMEMxASST XASSTHOLD XASSTWAIT + Mecr Expansion Memory Configuration Register Mecr30. Mecr Bit Definition CIT NOS 3 16-Bit PC Card Overview 26 -Bit PC Card Memory Map 33. Attribute Memory Space Write Commands 31. Common Memory Space Write Commands32. Common Memory Space Read Commands 34. Attribute Memory Space Read Commands 37 -Bit I/O Space Write Commands nIOIS16 = 38 -Bit I/O Space Read Commands nIOIS16 =External Logic for 16-Bit PC Card Implementation DIR Socket Expansion Card Interface Timing Diagrams and Parameters 29 -Bit PC Card Memory or I/O 16-Bit Half-word Access 30 -Bit PC Card I/O 16-Bit Access to 8-Bit Device Companion Chip Interface 31. Alternate Bus Master Mode 32. Variable Latency IO Alternate Bus Master Mode Gpio Reset NVDDFAULT/nBATTFAULT with Pmcridae DisabledNVDDFAULT/nBATTFAULT with Pmcridae Enabled Boot Time Defaults Options and Settings for Boot MemoryAlternate Booting Bootdef Read-Only Register Bootdef Bootdef 40. Bootdef Bitmap41. Valid Boot Configurations Based on Processor Type PKG Type Boot SEL Boot-Time Configurations Sxcnfg 34. Smrom Boot Time Configurations and Register Defaults Memory Interface Reset and Initialization SmromMdrefr 03CA 7FFF Hardware, Watchdog, or Sleep Reset Operation 42. Memory Controller Pin Reset ValuesPin Name PXA255 Processor Reset Value Memory Controller Memory Controller Register Summary Gpio Reset ProcedurePhysical Address Symbol Register Name 43. Memory Controller Register Summary Sheet 1 43. Memory Controller Register Summary Sheet 2 LCD Controller Features LCD Controller LCD Controller Block Diagram Enabling the Controller LCD Controller OperationPin Descriptions Pin Descriptions Disabling the Controller Resetting the ControllerDetailed Module Descriptions Input FIFOs Lookup Palette Temporal Modulated Energy Distribution Tmed Dithering Compare Range for Tmed Output FIFOs LCD Controller Pin Usage Passive Display Timing Pixel Data Pins LDDx6 DMA Active Display Timing LCD External Palette and Frame Buffers External Palette Buffer External Frame Buffer Palette Buffer Format Bits Per Pixel Data Memory Organization 10 Bits Per Pixel Data Memory Organization Passive Mode Functional Timing FrameBufferSize = 12. Passive Mode Start-of-Frame Timing Vsync Hsync Lbias Register Descriptions Lfclk Vsync Llclk Hsync Lbias LCD Controller Control Register 0 LCCR0 LCD Controller LDD LCD Controller Data Pin Utilization Sheet 1 Single Passive Screen Portion Pins LCD Controller Data Pin Utilization Sheet 2 LCCR0 Reset X X X X X X X X X X XLCCR0 Bit Definitions Sheet 1 0x44000000 Bit Reserved QDM DIS DPD LCD Controller Control Register 1 LCCR1LCCR0 Bit Definitions Sheet 2 PAS EFM IUM SFM LDM SDS CMS ENB LCD Controller BLW ELW HSW PPL LCD Controller Control Register 2 LCCR2LCCR1 Bit Definitions BLW LCD Controller BFW EFW VSW LPP LCD Controller Control Register 3 LCCR3LCCR2 Bit Definitions BFW LCD Controller LCD Controller 0x4400000C Bit Reserved Reset X X X X 0 0 0LCCR3 Bit Definitions Sheet 1 DPC BPP Frame Descriptors Reset X X XLCD Controller DMA LCCR3 Bit Definitions Sheet 2 FDADRx Bit Definitions LCD DMA Frame Descriptor Address Registers FDADRxLCD DMA Frame Source Address Registers FSADRx FDADR0 LCD DMA Frame ID Registers FIDRx FSADRx Bit DefinitionsFIDRx Bit Definitions LCD DMA Command Registers LDCMDx LDCMD1 10. LDCMDx Bit DefinitionsLDCMD0 PAL Bint BRA LCD DMA Frame Branch Registers FBRx11. FBRx Bit Definitions 0 0 0 0 X X 0 Bits Name Description LCD Controller Status Register Lcsr LCD Controller X X 0x44000038 Bit Reset X XLcsr Bit Definitions Sheet 1 EOF IUU IUL ABC BER SOF LDD 13. Liicr Bit Definitions LCD Controller Interrupt ID Register Liidr12. Lcsr Bit Definitions Sheet 2 Sint BS EOF QD OU IUU IUL ABC BER SOF LDD TBS Tmed RGB Seed Register Trgbr14. Trgbr Bit Definitions TRS Tmed Control Register TCR LCD Controller Register Summary 15. TCR Bit Definitions16. LCD Controller Register Summary Sheet 1 16. LCD Controller Register Summary Sheet 2 LCD Controller External Interface to Codec Signal DescriptionExternal Interface to Synchronous Serial Peripherals Name Direction Description Data Formats Data TransferSerial Data Formats for Transfer to/from Peripherals SSP Format Details Sspsclk Sspsfrm MSB SPI Format DetailsSspsclk Sspsfrm LSB Microwire Format Details Sspsclk Sspsfrm Ssptxd Ssprxd National Microwire* Frame Format Parallel Data Formats for Fifo Storage Fifo Operation and Data Transfers Using Programmed I/O Data TransfersUsing DMA Data Transfers Baud-Rate Generation SSP Serial Port Registers SSP Control Register 0 SSCR0 SSP Control Register 0 SSCR0 Data Size Select DSSSSCR0 Bit Definitions SCR Synchronous Serial Port Enable SSE Frame Format FRFExternal Clock Select ECS SSP Control Register 1 SSCR1 Serial Clock Rate SCRSSCR1 Bit Definitions Sheet 1 Loop Back Mode LBM Receive Fifo Interrupt Enable RIETransmit Fifo Interrupt Enable TIE SSCR1 Bit Definitions Sheet 2 Serial Clock Phase SPH Serial Clock Polarity SPOSspsclk SPO=0 Sspsclk SPO=1 Sspsfrm Ssptxd Receive Fifo Interrupt/DMA Threshold RFT Microwire Transmit Data Size MwdsTransmit Fifo Interrupt/DMA Threshold TFT Ssprxd Sspsclk SPO=0 Sspsclk SPO=1 Sspsfrm Ssptxd SSP Data Register Ssdr TFT and RFT Values for DMA ServicingSsdr Bit Definitions SSP Status Register Sssr RFL TFL ROR RFS TFS BSY RNE TNF Transmit Fifo Not Full Flag TNFSssr Bit Definitions RFL Receive Fifo Not Empty Flag RNE Transmit Fifo Service Request Flag TFSReceive Fifo Service Request Flag RFS SSP Busy Flag BSY SSP Controller Register Summary SSP Controller Register SummaryReceive Fifo Level RFL Address Abbreviation Full Name Synchronous Serial Port Controller SDA I2C Signal DescriptionSignal Name Input/Output Description SCL I2C Bus Definitions 2C Device Definition 2 I2C Bus Interface Modes Mode DescriptionOperational Blocks Modes of Operation Stop Star Start and Stop Bus StatesStart and Stop Bit Definitions Condition Start Condition No Start or Stop ConditionStop Condition ACK ACK NAKStart ACK Stop NAK I2C Bus Operation Serial Clock Line SCL GenerationData and Addressing Management 3 I2C Acknowledge Addressing a Slave Device Polling Arbitration SCL Arbitration SDA Arbitration Arbitration Procedure of Two Masters 2C Master Mode Definition Action Operation Master OperationsMaster Transactions Sheet 1 Master Transactions Sheet 2 Slave Operations Master-Receiver Read from Slave-Transmitter 2C Slave Action Mode Definition Operation Slave Transactions General Call Address ACK StopNAK Stop General Call Address Second Byte Definitions Least Second Write n Bytes as a Slave Slave Mode Programming ExamplesInitialize Unit Read n Bytes as a Slave Master Programming Examples Write 1 Byte as a Master Read 1 Byte as a Master Write 2 Bytes and Repeated Start Read 1 Byte as a Master Reset Conditions Read 2 Bytes as a Master Send Stop Using the AbortGlitch Suppression Logic 2 I2C Data Buffer Register Idbr Register Definitions1 I2C Bus Monitor Register Ibmr Ibmr Bit Definitions 3 I2C Control Register ICR Idbr Bit Definitions10. ICR Bit Definitions Sheet 1 10. ICR Bit Definitions Sheet 2 40301690 Bit ResetDisable interrupt Beie Irfie Iteie GCD IUE Receive mode 4 I2C Status Register ISR10. ICR Bit Definitions Sheet 3 40301698 Bit 11. ISR Bit Definitions Sheet 12C Status Register BED SAD 12. Isar Bit Definitions 5 I2C Slave Address Register Isar11. ISR Bit Definitions Sheet 2 BED SAD Gcad IRF ITE ALD SSD IBB I2C Bus Interface Unit Feature List UARTs Standard Uart Bluetooth UartFull Function Uart Compatibility with Name Type Description Signal DescriptionsUart Signal Descriptions Sheet 1 RXD Uart Signal Descriptions Sheet 2 Uart Operational DescriptionLSB MSB Reset Internal Register Descriptions Uart Register Addresses as Offsets of a Base Register AccessedReceive Buffer Register RBR RBR Bit Definitions Transmit Holding Register THR Divisor Latch Registers DLL and DLHTHR Bit Definitions Interrupt Enable Register IER DLL Bit DefinitionsDLH Bit Definitions Interrupt Identification Register IIR IER Bit Definitions Priority Level Interrupt origin Interrupt ConditionsIIR Bit Definitions Sheet 1 FIFOES10 IIR Bit Definitions Sheet 2 Interrupt ID Bits Interrupt SET/RESET FunctionFcrresetrf 10. Interrupt Identification Register Decode Sheet 1 11. FCR Bit Definitions Sheet 1 Fifo Control Register FCR10. Interrupt Identification Register Decode Sheet 2 ITL Line Control Register LCR 11. FCR Bit Definitions Sheet 2 12. LCR Bit Definitions Base+0x0CUart Dlab Stkyp EPS PEN STB WLS1 WLS0 Fifoe Line Status Register LSR13. LSR Bit Definitions Sheet 1 Temt 13. LSR Bit Definitions Sheet 2 Tdrq 13. LSR Bit Definitions Sheet 3 Uart Modem Control Register MCR14. MCR Bit Definitions Sheet 1 Loop OUT2 OUT1 RTS DTR Modem Status Register MSR 14. MCR Bit Definitions Sheet 2Base+0x10 Modem Control Register 15. MSR Bit Definitions Scratchpad Register SPR Fifo Interrupt Mode OperationCharacter Timeout Indication Interrupt Receive Interrupt Fifo Polled Mode Operation DMA RequestsTransmit Interrupt Slow Infrared Asynchronous Interface Trailing Bytes in the Receive FifoInfrared Selection Register ISR Operation 17. ISR Bit Definitions IR Transmit and Receive Example 19. Btuart Register Summary Sheet 1 Uart Register Summary18. Ffuart Register Summary Dlab Bit Name Description 19. Btuart Register Summary Sheet 2 20. Stuart Register Summary Btmcr Uart Register Differences21. Flow Control Registers in Btuart and Stuart Btmsr Ficp Signal Description Ficp Operation 11.2.1 4PPM Modulation PPM Modulation Encodings Control Field Frame FormatAddress Field Data Field CRC Field Baud Rate GenerationReceive Operation Transmit Operation Transmit and Receive FIFOs Trailing or Error Bytes in the Receive Fifo Ficp Register Definitions Ficp Control Register 0 ICCR0 ICCR0 Bit Definitions Sheet 1 TUS ICCR0 Bit Definitions Sheet 2TXE LBM Ficp Control Register 1 ICCR1 ICCR1 Bit Definitions Ficp Control Register 2 ICCR2 ICCR2 Bit Definitions Ficp Data Register Icdr Icrd Bit Definitions FRE Ficp Status Register 0 ICSR0ICSR0 Bit Definitions Sheet 1 RFS ICSR0 Bit Definitions Sheet 2 TUREIF Ficp Status Register 1 ICSR1 ICSR1 Bit Definitions Ficp Register Summary Ficp Register Summary USB Device Controller USB Overview USB Protocol Device ConfigurationEndpoint Configuration IN/OUT USB States Signalling LevelsBit Encoding Bus State UDC+/UDC- Pin Levels Field Formats Nrzi Bit Encoding Example Token Packet Type IN, OUT, and Setup Token Packet FormatPacket Formats Start of Frame Packet Type Handshake Packet Type Transaction FormatsData Packet Type Bulk Transaction Type Bulk Transaction Formats Isochronous Transaction TypeControl Transaction Type Isochronous Transaction Formats UDC Device Requests Interrupt Transaction Type10. Interrupt Transaction Formats Configuration 11. Host Device Request SummaryRequest Name Self-Powered Device UDC Hardware Connection When GPIOn and GPIOx are Different Pins When GPIOn and GPIOx are the Same Pin Bus-Powered Devices UDC OperationCase 1 EP0 Control Read Case 2 EP0 Control Read with a Premature Status Stage 12-14 Intel PXA255 Processor Developer’s Manual Case 4 EP0 No Data Command Software Enables the DMACase 5 EP1 Data Transmit BULK-IN Software Enables the EP1 Interrupt Case 6 EP2 Data Receive BULK-OUT Software Enables DMA Case 7 EP3 Data Transmit ISOCHRONOUS-INSoftware Allows the Megacell to Handle the Transaction Software Enables the EP3 Interrupt Software Enables the SOF InterruptCase 8 EP4 Data Receive ISOCHRONOUS-OUT Intel PXA255 Processor Developer’s Manual 12-19 Case 10 Reset Interrupt Case 9 EP5 Data Transmit INTERRUPT-IN UDC Register Definitions Case 11 Suspend InterruptCase 12 Resume Interrupt UDC Enable UDE UDC Control Register Udccr12. Udccr Bit Definitions UDC Active UDA Reset Interrupt Request RstirReset Interrupt Mask REM UDC Resume RSM UDC Control Function Register Udccfr ACK Control ModeACK Response Enable 13. UDC Control Function Register Packet Ready IPR UDC Endpoint 0 Control/Status Register UDCCS0OUT Packet Ready OPR 14. UDCCS0 Bit Definitions Sent Stall SST Device Remote Wakeup Feature DrwfFlush Tx Fifo FTF Force Stall FST UDC Endpoint x Control/Status Register UDCCS1/6/11 Setup Active SATransmit Fifo Service TFS 15. UDCCS1/6/11 Bit Definitions Transmit Packet Complete TPC Transmit Underrun TURBit 6 Reserved UDC Endpoint x Control/Status Register UDCCS2/7/12 Transmit Short Packet TSP16. UDCCS2/7/12 Bit Definitions Receive Packet Complete RPC Receive Fifo Service RFSDMA Enable DME Bit 2 Reserved UDC Endpoint x Control/Status Register UDCCS3/8/13 Receive Short Packet RSP17. UDCCS3/8/13 Bit Definitions UDC Endpoint x Control/Status Register UDCCS4/9/14 Bits 64 Reserved Receive Overflow ROF 18. UDCCS4/9/14 Bit Definitions UDC Endpoint x Control/Status Register UDCCS5/10/15 Bits 54 Reserved19. UDCCS5/10/15 Bit Definitions Sheet 1 19. UDCCS5/10/15 Bit Definitions Sheet 2 UDC Interrupt Control Register 0 UICR0 UICR0 Interrupt Mask Endpoint x IMx, Where x is 0 through20. UICR0 Bit Definitions IM7 IM6 IM5 IM4 IM3 IM2 IM1 IM0 21. UICR1 Bit Definitions Interrupt Mask Endpoint x IMx, where x is 8 throughUDC Interrupt Control Register 1 UICR1 UICR1 Endpoint 1 Interrupt Request IR1 UDC Status/Interrupt Register 0 USIR0Endpoint 0 Interrupt Request IR0 22. USIR0 Bit Definitions Endpoint 4 Interrupt Request IR4 Endpoint 2 Interrupt Request IR2Endpoint 3 Interrupt Request IR3 Endpoint 5 Interrupt Request IR5 Endpoint 9 Interrupt Request IR9 UDC Status/Interrupt Register 1 USIR1Endpoint 8 Interrupt Request IR8 Endpoint 10 Interrupt Request IR10 UDC Frame Number High Register Ufnhr UDC Frame Number MSB Fnmsb Isochronous Packet Error Endpoint 4 IPE4Isochronous Packet Error Endpoint 9 IPE9 24. Ufnhr Bit Definitions UDC Byte Count Register x UBCR2/4/7/9/12/14 Isochronous Packet Error Endpoint 14 IPE14UDC Frame Number Low Register Ufnlr Start of Frame Interrupt Mask SIM UDC Endpoint 0 Data Register UDDR0 Endpoint x Byte Count BC26. UBCR2/4/7/9/12/14 Bit Definitions 27. UDDR0 Bit Definitions UDC Endpoint x Data Register UDDR1/6/11UDC Endpoint x Data Register UDDR2/7/12 28. UDDR1/6/11 Bit Definitions 29. UDDR2/7/12 Bit Definitions UDC Endpoint x Data Register UDDR3/8/13UDC Endpoint x Data Register UDDR4/9/14 30. UDDR3/8/13 Bit Definitions 31. UDDR4/9/14 Bit Definitions USB Device Controller Register SummaryUDC Endpoint x Data Register UDDR5/10/15 32. UDDR5/10/15 Bit Definitions 33. USB Device Controller Register Summary Sheet 2 UfnhrUfnlr 33. USB Device Controller Register Summary Sheet 3 AC’97 Controller Unit External Interface to CODECs Signal Configuration StepsExample AC-link Name Direction Description summary SDATAIN0 SDATAIN1 AC-link Digital Serial Interface ProtocolSupported Data Stream Formats Sheet 1 Channel Slots Comments AC-link Audio Output Frame Sdataout Supported Data Stream Formats Sheet 2Sync AC-link Audio Output Frame Slot 0 Tag Phase Slot 1 Command Address Port Slot 1 Bit Definitions Slot 2 Command Data PortSlot 3 PCM Playback Left Channel Slot 2 Bit Definitions Slot 5 Modem Line Codec AC-link Audio Input Frame SdatainSlot 4 PCM Playback Right Channel Slots 6-11 Reserved Sync Slot 1 Status Address Port/SLOTREQ bits Input Slot 1 Bit Definitions Sheet 1Bit Description Slot 4 PCM Record Right Channel Slot 2 Status Data PortSlot 3 PCM Record Left Channel Slot 5 Optional Modem Line Codec Slots 7-11 Reserved AC-link Low Power ModePowering Down the AC-link Slot 12 I/O Status Waking up the AC-link Wake up triggered by the Codec Acunit Operation Cold AC’97 ResetWarm AC’97 Reset Wake Up Triggered by the Acunit Initialization 13-16 Intel PXA255 Processor Developer’s Manual Operational Flow for Accessing Codec Registers Clocks and Sampling Frequencies Transmit Fifo Errors Receive Fifo ErrorsFIFOs Interrupts Registers Global Control Register GCR GCR Bit Definitions Sheet 1 Warmrst Global Status Register GSRGCR Bit Definitions Sheet 2 Coldrst Rdcs GSR Bit Definitions Sheet 1Cdone Sdone Secres Prires SCR PCR Mint Point Piint PCM-Out Control Register Pocr GSR Bit Definitions Sheet 2Pocr Bit Definitions Sheet 1 PCM-In Control Register Picr Pocr Bit Definitions Sheet 210. Picr Bit Definitions 11. Posr Bit Definitions PCM-Out Status Register PosrPCMIn Status Register Pisr 12. Pisr Bit Definitions 13. CAR Bit Definitions Codec Access Register CARPCM Data Register Pcdr 14. Pcdr Bit Definitions 15. Mccr Bit Definitions Mic-In Control Register MccrMic-In Status Register Mcsr Mccr Register 17. Mcdr Bit Definitions Mic-In Data Register Mcdr16. Mcsr Bit Definitions Micindat 18. Mocr Bit Definitions Modem-Out Control Register MocrModem-In Control Register Micr Mocr Register 19. Micr Bit Definitions Modem-Out Status Register MosrModem-In Status Register Misr 20. Mosr Bit Definitions 22. Modr Bit Definitions Modem Data Register Modr21. Misr Bit Definitions Modemdat Accessing Codec Registers 11. Modem Transmit and Receive Operation 23. Address Mapping for Codec Registers Sheet 1 Processor Bit PhysicalAddress for a Primary Secondary Audio Codec Modem Codec 23. Address Mapping for Codec Registers Sheet 2 13.9 AC’97 Register Summary 24. Register Mapping Summary 13-36 Intel PXA255 Processor Developer’s Manual Inter-Integrated-Circuit Sound I2S Controller GP32/SYSCLK GP29/SDATAIN Controller Operation Disabling and Enabling Audio Replay Disabling and Enabling Audio Record Transmit Fifo Errors Receive Fifo ErrorsSerial Audio Clocks and Sampling Frequencies Supported Sampling Frequencies Fifo and Memory Format14.5.2 I2S and MSB-Justified Serial Audio Formats Sysclk = Bitclk = I2S Data Formats 16 bits Registers Serial Audio Controller Global Control Register SACR0 Special purpose Fifo Read/Write function SACR0 Bit Definitions Tfth and Rfth Values for DMA Servicing Suggested Tfth and Rfth for DMA servicingFifo Write/Read table Efwr Strf Drpl SACR1 Bit DefinitionsEnlbf Drec RFL Serial Audio Clock Divider Register SadivSASR0 Bit Definitions TFL Serial Audio Interrupt Clear Register Saicr Sadiv Bit DefinitionsSaicr Bit Definitions 10. Saimr Bit Descriptions Serial Audio Interrupt Mask Register SaimrSerial Audio Data Register Sadr 11. Sadr Bit Descriptions Transmit and Receive Fifo Accesses Through the Sadr 14.8 I2S Controller Register Summary 12. Register Memory Map Address Register Description Paddr90 Name MultiMediaCard Controller Command Token Format MMC Data Token FormatSPI Data Token Format Mmcmd Mmdat MMC Controller Functional Description CRC Intel PXA255 Processor Developer’s Manual 15-5 MMC Signal Description Signal DescriptionMMC Controller Reset Card Initialization Sequence MMC Mode Error Detection SPI Mode Clock Control Data FIFOs Response Data Fifo MmcresReceive Data FIFO, Mmcrxfifo Transmit Data FIFO, Mmctxfifo Card Communication Protocol DMA and Program I/O Basic, No Data, Command and Response Sequence Mmcclkrt Mmcspi Mmcresto Block Data Write Block Data Read Stream Data Write Busy Sequence Stream Data Read SPI Functionality Enabling SPI ModeMultiMediaCard Controller Operation Start and Stop Clock No Data Command and Response Sequence EraseSingle Data Block Write Single Block Read Multiple Block Write Multiple Block Read Stream Write Stream Read MMC Controller Registers Mmcstrpcl Register Mmcstat Bit Definitions Sheet 1 MMCStatus Register MmcstatMmcstrpcl Bit Definitions Strpcl Mmcclkrt Register Mmcclkrt Mmcstat Bit Definitions Sheet 2 Mmcspi Register Mmcspi Mmcclk Bit DefinitionsMmcspi Bit Definitions Sheet 1 Mmccmdat Register Mmccmdat Mmcspi Bit Definitions Sheet 2Mmccmdat Bit Definitions Sheet 1 Mmcresto Register Mmcresto Mmccmdat Bit Definitions Sheet 210. Mmcresto Bit Definitions Readto Mmcrdto Register Mmcrdto11. Mmcrdto Register Specifies the length of time before a data read time-out 12. Mmcblklen Bit Definitions Mmcblklen Register MmcblklenMmcnob Register Mmcnob 13. Mmcnob Bit Definitions 14. Mmcprtbuf Bit Definitions Mmcprtbuf Register MmcprtbufMmcimask Register Mmcimask 15. Mmcimask Bit Definitions Sheet 1 Mmcimask Register MultiMediaCard Controller Mmcireg Register Mmcireg15. Mmcimask Bit Definitions Sheet 2 4 3 2 1 16. Mmcireg Bit Definitions Mmccmd Register Mmccmd 18. Command Index Values Sheet 1CMD Comm Mode Abbreviation Index 17. Mmccmd Register 18. Command Index Values Sheet 2 Mmcargl Register Mmcargl 18. Command Index Values Sheet 3Mmcargh Register Mmcargh 19. Mmcargh Bit Definitions 22. MMCRXFIFO, Fifo Entry Mmcres Fifo21. MMCRES, Fifo Entry Responsedata 24. MMC Controller Registers Sheet 1 MultiMediaCard Controller Register Summary23. MMCTXFIFO, Fifo Entry Writedata 24. MMC Controller Registers Sheet 2 Features Network SSP Serial Port Processor and DMA Fifo Access SSP Serial Port I/O SignalsOperation Trailing Bytes in the Receive Fifo Data Formats 16-4 Intel PXA255 Processor Developer’s Manual TI Synchronous Serial Protocol* Details SPI Protocol Details Serial Clock Phase SPH Motorola SPI* Frame Protocol multiple transfers 16-8 Intel PXA255 Processor Developer’s Manual Microwire* Protocol Details PSP Details Programmable Serial Protocol multiple transfers Sspspsfrmp Programmable Serial Protocol PSP ParametersSspspscmode Sspspstrtdly Hi-Z on Ssptxd 11. TI SSP with SSCRTTE=1 and SSCRTTELP=0 Motorola SPI Programmable Serial Protocol 16-16 Intel PXA255 Processor Developer’s Manual Fifo Operation Baud-Rate Generation 16-18 Intel PXA255 Processor Developer’s Manual SCR SSE SSCR0 Bit Definitions Sheet 1SSCR0 FRF DSS Data Size Select SSCR0 Bit Definitions Sheet 2Edss SCR SSE Edss DSS SSCR1 Ttelp TTE EbceiSclkdir Sfrmdir Scfr SPH SPO LBM TIE RIE SSP Programmable Serial Protocol Register Sspsp Sspsp Bit Definitions Sheet 1 Sspsp Bit Definitions Sheet 2 SSP Time Out Register SstoSSP Interrupt Test Register Ssitr Ssto Bit Definitions Ssitr Bit Definitions Test Receive Fifo Service Request TrfsTest Transmit Fifo Service Request Ttfs Ssitr BCE CSS TUR Sssr Bit Definitions Sheet 1Sssr Tint Sssr Bit Definitions Sheet 2 SSP Busy Transmit Fifo Service RequestSssr Bit Definitions Sheet 3 Receive Fifo not Empty Ssdr Network SSP Serial Port Register Summary10. Nssp Register Address Map Data TRANSMIT/RECEIVE Data 16-30 Intel PXA255 Processor Developer’s Manual Hardware Uart Hardware Uart Uart Signal Descriptions Operation 17-4 Intel PXA255 Processor Developer’s Manual Character Timeout Interrupt Fifo Interrupt Mode OperationFifo Polled Mode Operation Receive Interrupt Fifo DMA Mode Operation DMA Receive Programming ErrorsDMA Error Handling Removing Trailing Bytes In DMA Mode Autoflow ControlAuto-Baud-Rate Detection 17-8 Intel PXA255 Processor Developer’s Manual Intel PXA255 Processor Developer’s Manual 17-9 Divisor Latch Registers DLL and DLH Receive Buffer Register RBRTransmit Holding Register THR Bit Reserved Byte Bits Name Description 318 DLL Interrupt Enable Register IERDivisor Latch Register High DLH Bit Definitions DLH Physical Address Interrupt Enable Register IER 0x41600004 Bit Reset ? ? ? ? ? ? ? Bits Name? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? 0 0 0 0 0 0 0 Description ABL TOD IID Interrupt Identification Register IIRIIR NIP 0x41600008 Priority Type Source Reset ControlInterrupt Identification Register Decode Sheet 1 ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? 0 0 ? 0 0 0 0 Fifo Control Register FCR Interrupt Identification Register Decode Sheet 210. FCR Bit Definitions Sheet 1 Receive Fifo Occupancy Register for 10. FCR Bit Definitions Sheet 211. for Bit Definitions 12. ABR Bit Definitions Auto-Baud Control Register ABRAuto-Baud Count Register ACR ABT 14. LCR Bit Definitions Sheet 1 Line Control Register LCR13. ACR Bit Definitions ACR Line Control Register LCR PXA255 Processor Hardware Uart Line Status Register LSR14. LCR Bit Definitions Sheet 2 Dlab Stkyp EPS PEN STB WLS 15. LSR Bit Definitions Sheet 1 0x41600014 Bit? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? 0 1 1 0 0 0 0 Bits Line Status Register LSR PXA255 Processor Hardware Uart Modem Control Register MCR15. LSR Bit Definitions Sheet 2 0 0 0 0 Bits Name Description Physical Address Modem Control Register MCR 0x41600010 Bit Reset ? ? ? ? ? ? ? Bits16. MCR Bit Definitions Sheet 1 AFE Modem Status Register MSR 16. MCR Bit Definitions Sheet 217. MSR Bit Definitions Sheet 1 17. MSR Bit Definitions Sheet 2 Scratchpad Register SCRInfrared Selection Register ISR 18. SCR Bit Definitions 20. Hwuart Register Locations Sheet 1 Hardware Uart Register Summary19. ISR Bit Definitions Rxpl Txpl Xmode Rcveir Xmitir 20. Hwuart Register Locations Sheet 2 Intel PXA255 Processor Developer’s Manual 17-27