Intel® Agilex™ Hard Processor System Technical Reference Manual
                    
                        ID
                        683567
                    
                
                
                    Date
                    2/14/2023
                
                
                    Public
                
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                        1. Intel® Agilex™ Hard Processor System Technical Reference Manual Revision History
                    
                
                    
                        2. Introduction to the Hard Processor System
                    
                    
                
                    
                        3. Cortex-A53 MPCore Processor
                    
                    
                
                    
                        4. Cache Coherency Unit
                    
                    
                
                    
                        5. System Memory Management Unit
                    
                    
                
                    
                        6. System Interconnect
                    
                    
                
                    
                        7. Bridges
                    
                    
                
                    
                        8. DMA Controller
                    
                    
                
                    
                        9. On-Chip RAM
                    
                    
                
                    
                        10. Error Checking and Correction Controller
                    
                    
                
                    
                        11. Clock Manager
                    
                    
                
                    
                        12. System Manager
                    
                    
                
                    
                        13. Reset Manager
                    
                    
                
                    
                        14. Hard Processor System I/O Pin Multiplexing
                    
                    
                
                    
                        15. NAND Flash Controller
                    
                    
                
                    
                        16. SD/MMC Controller
                    
                    
                
                    
                        17. Ethernet Media Access Controller
                    
                    
                
                    
                        18. USB 2.0 OTG Controller
                    
                    
                
                    
                        19. SPI Controller
                    
                    
                
                    
                        20. I2C Controller
                    
                    
                
                    
                        21. UART Controller
                    
                    
                
                    
                        22. General-Purpose I/O Interface
                    
                    
                
                    
                        23. Timers
                    
                    
                
                    
                        24. Watchdog Timers
                    
                    
                
                    
                        25. CoreSight Debug and Trace
                    
                    
                
                    
                        A. Booting and Configuration
                    
                    
                
                    
                        B. Accessing the Secure Device Manager Quad SPI Flash Controller through HPS
                    
                    
                
            
        
                                    
                                    
                                        
                                        
                                            2.2.1. HPS Block Diagram
                                        
                                        
                                    
                                        
                                        
                                            2.2.2. Cortex-A53 MPCore Processor
                                        
                                        
                                    
                                        
                                        
                                            2.2.3. Cache Coherency Unit
                                        
                                        
                                    
                                        
                                        
                                            2.2.4. System Memory Management Unit
                                        
                                        
                                    
                                        
                                            2.2.5. HPS Interfaces
                                        
                                        
                                        
                                    
                                        
                                            2.2.6. System Interconnect
                                        
                                        
                                        
                                    
                                        
                                        
                                            2.2.7. On-Chip RAM
                                        
                                        
                                    
                                        
                                            2.2.8. Flash Memory Controllers
                                        
                                        
                                        
                                    
                                        
                                            2.2.9. System Modules
                                        
                                        
                                        
                                    
                                        
                                            2.2.10. Interface Peripherals
                                        
                                        
                                        
                                    
                                        
                                        
                                            2.2.11. CoreSight* Debug and Trace
                                        
                                        
                                    
                                        
                                        
                                            2.2.12. Hard Processor System I/O Pin Multiplexing
                                        
                                        
                                    
                                
                            
                                    
                                    
                                        
                                            3.5.1. Exception Levels
                                        
                                        
                                        
                                    
                                        
                                            3.5.2. Virtualization
                                        
                                        
                                        
                                    
                                        
                                            3.5.3. Memory Management Unit
                                        
                                        
                                        
                                    
                                        
                                            3.5.4. Level 1 Caches
                                        
                                        
                                        
                                    
                                        
                                        
                                            3.5.5. Level 2 Memory System
                                        
                                        
                                    
                                        
                                            3.5.6. Snoop Control Unit
                                        
                                        
                                        
                                    
                                        
                                        
                                            3.5.7. Cryptographic Extensions
                                        
                                        
                                    
                                        
                                            3.5.8. NEON Multimedia Processing Engine
                                        
                                        
                                        
                                    
                                        
                                        
                                            3.5.9. Floating Point Unit
                                        
                                        
                                    
                                        
                                        
                                            3.5.10. ACE Bus Interface
                                        
                                        
                                    
                                        
                                        
                                            3.5.11. Abort Handling
                                        
                                        
                                    
                                        
                                            3.5.12. Cache Protection
                                        
                                        
                                        
                                    
                                        
                                            3.5.13. Generic Interrupt Controller
                                        
                                        
                                        
                                    
                                        
                                            3.5.14. Generic Timers
                                        
                                        
                                        
                                    
                                        
                                            3.5.15. Debug Modules
                                        
                                        
                                        
                                    
                                        
                                        
                                            3.5.16. Cache Coherency Unit
                                        
                                        
                                    
                                        
                                        
                                            3.5.17. Clock Sources
                                        
                                        
                                    
                                
                            
                                    
                                    
                                        
                                        
                                            5.4.1. Translation Stages
                                        
                                        
                                    
                                        
                                            5.4.2. Exception Levels
                                        
                                        
                                        
                                    
                                        
                                        
                                            5.4.3. Translation Regimes
                                        
                                        
                                    
                                        
                                            5.4.4. Translation Buffer Unit
                                        
                                        
                                        
                                    
                                        
                                            5.4.5. Translation Control Unit
                                        
                                        
                                        
                                    
                                        
                                        
                                            5.4.6. Security State Determination
                                        
                                        
                                    
                                        
                                        
                                            5.4.7. Stream ID
                                        
                                        
                                    
                                        
                                        
                                            5.4.8. Quality of Service Arbitration
                                        
                                        
                                    
                                        
                                        
                                            5.4.9. System Memory Management Unit Interrupts
                                        
                                        
                                    
                                        
                                        
                                            5.4.10. System Memory Management Unit Reset
                                        
                                        
                                    
                                        
                                        
                                            5.4.11. System Memory Management Unit Clocks
                                        
                                        
                                    
                                
                            
                        
                        
                            
                            
                                15.1. NAND Flash Controller Features
                            
                        
                            
                                15.2. NAND Flash Controller Block Diagram and System Integration
                            
                            
                        
                            
                            
                                15.3. NAND Flash Controller Signal Descriptions
                            
                        
                            
                                15.4. Functional Description of the NAND Flash Controller
                            
                            
                        
                            
                                15.5. NAND Flash Controller Programming Model
                            
                            
                        
                            
                            
                                15.6. NAND Flash Controller Address Map and Register Definitions
                            
                        
                    
                
                                                
                                                
                                                    
                                                    
                                                        15.5.1.1. NAND Flash Controller Optimization Sequence
                                                    
                                                    
                                                
                                                    
                                                    
                                                        15.5.1.2. Device Initialization Sequence
                                                    
                                                    
                                                
                                                    
                                                    
                                                        15.5.1.3. Device Operation Control
                                                    
                                                    
                                                
                                                    
                                                    
                                                        15.5.1.4. ECC Enabling
                                                    
                                                    
                                                
                                                    
                                                    
                                                        15.5.1.5. NAND Flash Controller Performance Registers
                                                    
                                                    
                                                
                                                    
                                                        15.5.1.6. Interrupt and DMA Enabling
                                                    
                                                    
                                                    
                                                
                                                    
                                                    
                                                        15.5.1.7. Timing Registers
                                                    
                                                    
                                                
                                                    
                                                    
                                                        15.5.1.8. Registers to Ignore
                                                    
                                                    
                                                
                                            
                                        
                                                            
                                                            
                                                                
                                                                
                                                                    16.4.2.5.1. Internal DMA Controller Descriptors
                                                                
                                                                
                                                            
                                                                
                                                                
                                                                    16.4.2.5.2. Internal DMA Controller Descriptor Address
                                                                
                                                                
                                                            
                                                                
                                                                
                                                                    16.4.2.5.3. Internal DMA Controller Descriptor Fields
                                                                
                                                                
                                                            
                                                                
                                                                
                                                                    16.4.2.5.4. Host Bus Burst Access
                                                                
                                                                
                                                            
                                                                
                                                                
                                                                    16.4.2.5.5. Host Data Buffer Alignment
                                                                
                                                                
                                                            
                                                                
                                                                
                                                                    16.4.2.5.6. Buffer Size Calculations
                                                                
                                                                
                                                            
                                                                
                                                                
                                                                    16.4.2.5.7. Internal DMA Controller Interrupts
                                                                
                                                                
                                                            
                                                                
                                                                
                                                                    16.4.2.5.8. Internal DMA Controller Functional State Machine†
                                                                
                                                                
                                                            
                                                        
                                                    
                                                            
                                                            
                                                                
                                                                
                                                                    16.4.3.1.1. Load Command Parameters
                                                                
                                                                
                                                            
                                                                
                                                                
                                                                    16.4.3.1.2. Send Command and Receive Response
                                                                
                                                                
                                                            
                                                                
                                                                
                                                                    16.4.3.1.3. Send Response to BIU
                                                                
                                                                
                                                            
                                                                
                                                                
                                                                    16.4.3.1.4. Driving P-bit to the CMD Pin
                                                                
                                                                
                                                            
                                                                
                                                                
                                                                    16.4.3.1.5. Polling the CCS
                                                                
                                                                
                                                            
                                                                
                                                                
                                                                    16.4.3.1.6. CCS Detection and Interrupt to Host Processor
                                                                
                                                                
                                                            
                                                                
                                                                
                                                                    16.4.3.1.7. CCS Timeout
                                                                
                                                                
                                                            
                                                                
                                                                
                                                                    16.4.3.1.8. Send CCSD Command
                                                                
                                                                
                                                            
                                                                
                                                                
                                                                    16.4.3.1.9. I/O transmission delay (NACIO Timeout)
                                                                
                                                                
                                                            
                                                        
                                                    
                                    
                                    
                                        
                                            16.5.1. Software and Hardware Restrictions†
                                        
                                        
                                        
                                    
                                        
                                        
                                            16.5.2. Initialization
                                        
                                        
                                    
                                        
                                        
                                            16.5.3. Controller/DMA/FIFO Buffer Reset Usage
                                        
                                        
                                    
                                        
                                            16.5.4. Non-Data Transfer Commands
                                        
                                        
                                        
                                    
                                        
                                            16.5.5. Data Transfer Commands
                                        
                                        
                                        
                                    
                                        
                                            16.5.6. Transfer Stop and Abort Commands
                                        
                                        
                                        
                                    
                                        
                                            16.5.7. Internal DMA Controller Operations
                                        
                                        
                                        
                                    
                                        
                                            16.5.8. Commands for SDIO Card Devices
                                        
                                        
                                        
                                    
                                        
                                            16.5.9. CE-ATA Data Transfer Commands
                                        
                                        
                                        
                                    
                                        
                                            16.5.10. Card Read Threshold
                                        
                                        
                                        
                                    
                                        
                                        
                                            16.5.11. Interrupt and Error Handling
                                        
                                        
                                    
                                        
                                            16.5.12. Booting Operation for eMMC and MMC
                                        
                                        
                                        
                                    
                                
                            
                                                
                                                
                                                    
                                                    
                                                        16.5.12.1. Boot Operation by Holding Down the CMD Line
                                                    
                                                    
                                                
                                                    
                                                    
                                                        16.5.12.2. Boot Operation for eMMC Card Device
                                                    
                                                    
                                                
                                                    
                                                        16.5.12.3. Boot Operation for Removable MMC4.3, MMC4.4 and MMC4.41 Cards
                                                    
                                                    
                                                    
                                                
                                                    
                                                    
                                                        16.5.12.4. Alternative Boot Operation
                                                    
                                                    
                                                
                                                    
                                                    
                                                        16.5.12.5. Alternative Boot Operation for eMMC Card Devices
                                                    
                                                    
                                                
                                                    
                                                        16.5.12.6. Alternative Boot Operation for MMC4.3 Cards
                                                    
                                                    
                                                    
                                                
                                            
                                        
                        
                        
                            
                                17.1. Features of the Ethernet MAC
                            
                            
                        
                            
                            
                                17.2. EMAC Block Diagram and System Integration
                            
                        
                            
                            
                                17.3. Distributed Virtual Memory Support
                            
                        
                            
                                17.4. EMAC Controller Signal Description
                            
                            
                        
                            
                                17.5. EMAC Internal Interfaces
                            
                            
                        
                            
                                17.6. Functional Description of the EMAC
                            
                            
                        
                            
                                17.7. Ethernet MAC Programming Model
                            
                            
                        
                            
                            
                                17.8. Ethernet MAC Address Map and Register Definitions
                            
                        
                    
                
                                    
                                    
                                        
                                        
                                            17.6.1. Transmit and Receive Data FIFO Buffers
                                        
                                        
                                    
                                        
                                            17.6.2. DMA Controller
                                        
                                        
                                        
                                    
                                        
                                            17.6.3. Descriptor Overview
                                        
                                        
                                        
                                    
                                        
                                            17.6.4. IEEE 1588-2002 Timestamps
                                        
                                        
                                        
                                    
                                        
                                            17.6.5. IEEE 1588-2008 Advanced Timestamps
                                        
                                        
                                        
                                    
                                        
                                            17.6.6. IEEE 802.3az Energy Efficient Ethernet
                                        
                                        
                                        
                                    
                                        
                                        
                                            17.6.7. Checksum Offload
                                        
                                        
                                    
                                        
                                            17.6.8. Frame Filtering
                                        
                                        
                                        
                                    
                                        
                                            17.6.9. Clocks and Resets
                                        
                                        
                                        
                                    
                                        
                                        
                                            17.6.10. Interrupts
                                        
                                        
                                    
                                
                            
                                                            
                                                            
                                                                
                                                                
                                                                    17.6.8.1.1. Unicast Destination Address Filter
                                                                
                                                                
                                                            
                                                                
                                                                
                                                                    17.6.8.1.2. Multicast Destination Address Filter
                                                                
                                                                
                                                            
                                                                
                                                                
                                                                    17.6.8.1.3. Hash or Perfect Address Filter
                                                                
                                                                
                                                            
                                                                
                                                                
                                                                    17.6.8.1.4. Broadcast Address Filter
                                                                
                                                                
                                                            
                                                                
                                                                
                                                                    17.6.8.1.5. Unicast Source Address Filter
                                                                
                                                                
                                                            
                                                                
                                                                
                                                                    17.6.8.1.6. Inverse Filtering Operation (Invert the Filter Match Result at Final Output)
                                                                
                                                                
                                                            
                                                                
                                                                
                                                                    17.6.8.1.7. Destination and Source Address Filtering Summary
                                                                
                                                                
                                                            
                                                        
                                                    
                                    
                                    
                                        
                                        
                                            17.7.1. System Level EMAC Configuration Registers
                                        
                                        
                                    
                                        
                                        
                                            17.7.2. EMAC FPGA Interface Initialization
                                        
                                        
                                    
                                        
                                        
                                            17.7.3. EMAC HPS Interface Initialization
                                        
                                        
                                    
                                        
                                        
                                            17.7.4. DMA Initialization
                                        
                                        
                                    
                                        
                                        
                                            17.7.5. EMAC Initialization and Configuration
                                        
                                        
                                    
                                        
                                        
                                            17.7.6. Performing Normal Receive and Transmit Operation
                                        
                                        
                                    
                                        
                                        
                                            17.7.7. Stopping and Starting Transmission
                                        
                                        
                                    
                                        
                                            17.7.8. Programming Guidelines for Energy Efficient Ethernet
                                        
                                        
                                        
                                    
                                        
                                            17.7.9. Programming Guidelines for Flexible Pulse-Per-Second (PPS) Output
                                        
                                        
                                        
                                    
                                
                            
                        
                        
                            
                                18.1. Features of the USB OTG Controller
                            
                            
                        
                            
                            
                                18.2. Block Diagram and System Integration
                            
                        
                            
                            
                                18.3. Distributed Virtual Memory Support
                            
                        
                            
                            
                                18.4. USB 2.0 ULPI PHY Signal Description
                            
                        
                            
                                18.5. Functional Description of the USB OTG Controller
                            
                            
                        
                            
                                18.6. USB OTG Controller Programming Model
                            
                            
                        
                            
                            
                                18.7. USB 2.0 OTG Controller Address Map and Register Definitions
                            
                        
                    
                
                                    
                                    
                                        
                                        
                                            24.4.1. Setting the Timeout Period Values
                                        
                                        
                                    
                                        
                                        
                                            24.4.2. Selecting the Output Response Mode
                                        
                                        
                                    
                                        
                                        
                                            24.4.3. Enabling and Initially Starting a Watchdog Timers
                                        
                                        
                                    
                                        
                                        
                                            24.4.4. Reloading a Watchdog Counter
                                        
                                        
                                    
                                        
                                        
                                            24.4.5. Pausing a Watchdog Timers
                                        
                                        
                                    
                                        
                                        
                                            24.4.6. Disabling and Stopping a Watchdog Timers
                                        
                                        
                                    
                                        
                                        
                                            24.4.7. Watchdog Timers State Machine
                                        
                                        
                                    
                                
                            
                        
                        
                            
                            
                                25.1. Features of CoreSight Debug and Trace
                            
                        
                            
                            
                                25.2. ARM® CoreSight Documentation
                            
                        
                            
                            
                                25.3. CoreSight Debug and Trace Block Diagram
                            
                        
                            
                                25.4. Functional Description of CoreSight Debug and Trace
                            
                            
                        
                            
                                25.5. CoreSight Debug and Trace Programming Model
                            
                            
                        
                            
                            
                                25.6. CoreSight Debug and Trace Address Map and Register Definitions
                            
                        
                    
                
                                    
                                    
                                        
                                            25.4.1. Debug Access Port
                                        
                                        
                                        
                                    
                                        
                                        
                                            25.4.2. CoreSight SoC-400 Timestamp Generator
                                        
                                        
                                    
                                        
                                        
                                            25.4.3. System Trace Macrocell
                                        
                                        
                                    
                                        
                                        
                                            25.4.4. Trace Funnel
                                        
                                        
                                    
                                        
                                            25.4.5. CoreSight Trace Memory Controller
                                        
                                        
                                        
                                    
                                        
                                        
                                            25.4.6. AMBA Trace Bus Replicator
                                        
                                        
                                    
                                        
                                        
                                            25.4.7. Trace Port Interface Unit
                                        
                                        
                                    
                                        
                                        
                                            25.4.8. NoC Trace Ports
                                        
                                        
                                    
                                        
                                            25.4.9. Embedded Cross Trigger System
                                        
                                        
                                        
                                    
                                        
                                        
                                            25.4.10. Embedded Trace Macrocell
                                        
                                        
                                    
                                        
                                        
                                            25.4.11. HPS Debug APB Interface
                                        
                                        
                                    
                                        
                                            25.4.12. FPGA Interface
                                        
                                        
                                        
                                    
                                        
                                        
                                            25.4.13. Debug Clocks
                                        
                                        
                                    
                                        
                                        
                                            25.4.14. Debug Resets
                                        
                                        
                                    
                                
                            
                        
                        
                            
                            
                                B.1. Features of the Quad SPI Flash Controller
                            
                        
                            
                            
                                B.2. Taking Ownership of Quad SPI Controller
                            
                        
                            
                            
                                B.3. Quad SPI Flash Controller Block Diagram and System Integration
                            
                        
                            
                            
                                B.4. Quad SPI Flash Controller Signal Description
                            
                        
                            
                                B.5. Functional Description of the Quad SPI Flash Controller
                            
                            
                        
                            
                                B.6. Quad SPI Flash Controller Programming Model
                            
                            
                        
                            
                            
                                B.7. Accessing the SDM Quad SPI Flash Controller Through HPS Address Map and Register Definitions
                            
                        
                    
                
                                    
                                    
                                        
                                        
                                            B.5.1. Overview
                                        
                                        
                                    
                                        
                                            B.5.2. Data Slave Interface
                                        
                                        
                                        
                                    
                                        
                                        
                                            B.5.3. SPI Legacy Mode
                                        
                                        
                                    
                                        
                                            B.5.4. Register Slave Interface
                                        
                                        
                                        
                                    
                                        
                                        
                                            B.5.5. Local Memory Buffer
                                        
                                        
                                    
                                        
                                        
                                            B.5.6. Arbitration between Direct/Indirect Access Controller and STIG
                                        
                                        
                                    
                                        
                                        
                                            B.5.7. Configuring the Flash Device
                                        
                                        
                                    
                                        
                                        
                                            B.5.8. XIP Mode
                                        
                                        
                                    
                                        
                                        
                                            B.5.9. Write Protection
                                        
                                        
                                    
                                        
                                        
                                            B.5.10. Data Slave Sequential Access Detection
                                        
                                        
                                    
                                        
                                        
                                            B.5.11. Clocks
                                        
                                        
                                    
                                        
                                        
                                            B.5.12. Resets
                                        
                                        
                                    
                                        
                                        
                                            B.5.13. Interrupts
                                        
                                        
                                    
                                
                            10.4.4.4.1. Register Interface Tests
You can correct memory errors and test the memory register interface through registers in the ECC Controller.
    The following registers can be used to test and correct memory: 
    
 
  - ECC_Addrbus: Holds the address of the memory and ECC data.
- ECC_RData3bus through ECC_RData0bus: Holds memory data from a read access.
- ECC_WData3bus through ECC_WData0bus: Holds the data to be written to memory.
- ECC_RDataecc1bus and ECC_RDataecc0bus: Holds the ECC data from a read access.
- ECC_WDataecc1bus and ECC_WDataecc0bus: Holds the ECC data to be written to memory.
- ECC_accctrl: Configures the access as a read or a write and enables memory and ECC data overwrites.
- ECC_startacc: Initiates the register interface access of memory data or ECC data.
Single-Bit Error Test for DMA ECC RAM
 This sequence tests the single-bit error detection and correction in the ECC decoder of the DMA ECC RAM. 
   
 
   - Write data to the ECC_WData3bus through ECC_WData0bus registers.
- Set the ECC_EN bit in the CTRL register to enable the ECC detection and correction logic.
- Set the DBEN bit in the ECC_dbytectrl register.
- Select the address bus to write the data to by programming the ECC_Addrbus register.
-  In the ECC_accctrl register, program the following bits: 
     - RDWR=1
- ECCOVR=0
- DATAOVR=1
 
- Set the ENBUS* bit in the ECC_startacc register to trigger an indirect write access.
- Clear the ECC_EN bit in the CTRL register to disable the ECC detection and correction logic.
- Write a data value that has one bit altered in the ECC_WData3bus through ECC_WData0bus registers to the same address.
- Set the ENBUS* bit in the ECC_startacc register to trigger an indirect write access.
-  In the ECC_accctrl register, program the following bits: 
     - RDWR=0
- ECCOVR=1
- DATAOVR=1
 
- Set the ECC_EN bit in the CTRL register to enable the ECC detection and correction logic.
-  Set the ENBUS* bit in the ECC_startacc register to trigger an indirect write access. 
     If you have configured an interrupt to trigger for a single-bit error, then expect it to trigger after these steps have completed. If you read back the data at the same address using the ECC_RData*bus register, expect to see a corrected data result from the memories.
Single-Bit Error Test for Word-Writeable Memories
 This sequence tests the single-bit error detection and correction in the ECC decoder of the word-writeable ECC RAMs. 
   
 
   - Write data to the ECC_WData3bus through ECC_WData0bus registers.
- Set the ECC_EN bit in the CTRL register to enable the ECC detection and correction logic.
- Set the DBEN bit in the ECC_dbytectrl register.
- Select the address bus to write the data to by programming the ECC_Addrbus register.
-  In the ECC_accctrl register, program the following bits: 
     - RDWR=1
- ECCOVR=0
- DATAOVR=1
 
- Set the ENBUS* bit in the ECC_startacc register to trigger an indirect write access.
-  In the ECC_accctrl register, program the following bits: 
     - RDWR=0
- ECCOVR=1
- DATAOVR=0
 
- Set the ENBUS* bit in the ECC_startacc register to trigger an indirect write access.
- Write a data value that has one bit altered in the ECC_WData3bus through ECC_WData0bus registers to the same address.
- Read the resultant data from the ECC_RDataecc*bus registers at the same address.
- Write the value from the ECC_RDataecc*bus registers into the ECC_WDataecc*bus registers.
-  In the ECC_accctrl register, program the following bits: 
     - RDWR=1
- ECCOVR=1
- DATAOVR=1
 
- Set the ENBUS* bit in the ECC_startacc register to trigger an indirect write access.
-  In the ECC_accctrl register, program the following bits: 
     - RDWR=0
- ECCOVR=1
- DATAOVR=1
 
-  Set the ENBUS* bit in the ECC_startacc register to trigger an indirect write access. 
     If you have configured an interrupt to trigger for a single-bit error, then expect it to trigger after these steps have completed. If you read back the data at the same address using the ECC_RData*bus register, expect to see a corrected data result from the memories.
Double-Bit Error Test
 This sequence tests the double-bit error detection in the ECC decoder. 
   
 
   - Enable the ECC by setting the ECC_EN bit in the CTRL register.
- Set the Data override (DATAOVR) bit in the ECC_accctrl register.
- Write data to an address location in memory using a normal memory write. The correct ECC data should be generated.
- Write a data value that has two bits altered in the ECC_WData3bus through ECC_WData0bus registers and write the address of the memory location in the ECC_Addrbus.
- Configure the ECC_accctrl register to a write and set the ENBUSA bit of the ECC_startacc register to initiate the write. If the memory is dual-ported, an ENBUSB bit could optionally be enabled depending on the port access.
- Read the same memory location using a normal memory read access. Expect a double-bit error to be logged without data correction. Refer to the Error Logging section for more details about identifying errors.