SPRSP92D February   2023  – December 2024 AM69 , AM69A

PRODUCTION DATA  

  1.   1
  2. Features
  3. Applications
  4. Description
    1. 3.1 Functional Block Diagram
  5. Device Comparison
  6. Terminal Configuration and Functions
    1. 5.1 Pin Diagrams
    2. 5.2 Pin Attributes
      1.      10
      2.      11
    3. 5.3 Signal Descriptions
      1.      13
      2. 5.3.1  ADC
        1. 5.3.1.1 MCU Domain
          1.        16
          2.        17
          3.        18
      3. 5.3.2  DDRSS
        1. 5.3.2.1 MAIN Domain
          1.        21
          2.        22
          3.        23
          4.        24
      4. 5.3.3  GPIO
        1. 5.3.3.1 MAIN Domain
          1.        27
        2. 5.3.3.2 WKUP Domain
          1.        29
      5. 5.3.4  I2C
        1. 5.3.4.1 MAIN Domain
          1.        32
          2.        33
          3.        34
          4.        35
          5.        36
          6.        37
          7.        38
        2. 5.3.4.2 MCU Domain
          1.        40
          2.        41
        3. 5.3.4.3 WKUP Domain
          1.        43
      6. 5.3.5  I3C
        1. 5.3.5.1 MCU Domain
          1.        46
      7. 5.3.6  MCAN
        1. 5.3.6.1 MAIN Domain
          1.        49
          2.        50
          3.        51
          4.        52
          5.        53
          6.        54
          7.        55
          8.        56
          9.        57
          10.        58
          11.        59
          12.        60
          13.        61
          14.        62
          15.        63
          16.        64
          17.        65
          18.        66
        2. 5.3.6.2 MCU Domain
          1.        68
          2.        69
      8. 5.3.7  MCSPI
        1. 5.3.7.1 MAIN Domain
          1.        72
          2.        73
          3.        74
          4.        75
          5.        76
          6.        77
          7.        78
        2. 5.3.7.2 MCU Domain
          1.        80
          2.        81
      9. 5.3.8  UART
        1. 5.3.8.1 MAIN Domain
          1.        84
          2.        85
          3.        86
          4.        87
          5.        88
          6.        89
          7.        90
          8.        91
          9.        92
          10.        93
        2. 5.3.8.2 MCU Domain
          1.        95
        3. 5.3.8.3 WKUP Domain
          1.        97
      10. 5.3.9  MDIO
        1. 5.3.9.1 MAIN Domain
          1.        100
          2.        101
        2. 5.3.9.2 MCU Domain
          1.        103
      11. 5.3.10 UFS
        1. 5.3.10.1 MAIN Domain
          1.        106
      12. 5.3.11 CPSW2G
        1. 5.3.11.1 MAIN Domain
          1.        109
        2. 5.3.11.2 MCU Domain
          1.        111
      13. 5.3.12 SGMII
        1. 5.3.12.1 MAIN Domain
          1.        114
      14. 5.3.13 ECAP
        1. 5.3.13.1 MAIN Domain
          1.        117
          2.        118
          3.        119
      15. 5.3.14 EQEP
        1. 5.3.14.1 MAIN Domain
          1.        122
          2.        123
          3.        124
      16. 5.3.15 EPWM
        1. 5.3.15.1 MAIN Domain
          1.        127
          2.        128
          3.        129
          4.        130
          5.        131
          6.        132
          7.        133
      17. 5.3.16 USB
        1. 5.3.16.1 MAIN Domain
          1.        136
      18. 5.3.17 Display Port
        1. 5.3.17.1 MAIN Domain
          1.        139
      19. 5.3.18 PCIE
        1. 5.3.18.1 MAIN Domain
          1.        142
      20. 5.3.19 SERDES
        1. 5.3.19.1 MAIN Domain
          1.        145
          2.        146
          3.        147
          4.        148
      21. 5.3.20 DSI
        1. 5.3.20.1 MAIN Domain
          1.        151
          2.        152
      22. 5.3.21 CSI
        1. 5.3.21.1 MAIN Domain
          1.        155
          2.        156
          3.        157
      23. 5.3.22 MCASP
        1. 5.3.22.1 MAIN Domain
          1.        160
          2.        161
          3.        162
          4.        163
          5.        164
      24. 5.3.23 DMTIMER
        1. 5.3.23.1 MAIN Domain
          1.        167
        2. 5.3.23.2 MCU Domain
          1.        169
      25. 5.3.24 CPTS
        1. 5.3.24.1 MAIN Domain
          1.        172
        2. 5.3.24.2 MCU Domain
          1.        174
      26. 5.3.25 DSS
        1. 5.3.25.1 MAIN Domain
          1.        177
      27. 5.3.26 GPMC
        1. 5.3.26.1 MAIN Domain
          1.        180
      28. 5.3.27 MMC
        1. 5.3.27.1 MAIN Domain
          1.        183
          2.        184
      29. 5.3.28 OSPI
        1. 5.3.28.1 MCU Domain
          1.        187
          2.        188
      30. 5.3.29 Hyperbus
        1. 5.3.29.1 MCU Domain
          1.        191
      31. 5.3.30 Emulation and Debug
        1. 5.3.30.1 MAIN Domain
          1.        194
          2.        195
      32. 5.3.31 System and Miscellaneous
        1. 5.3.31.1 Boot Mode configuration
          1.        198
        2. 5.3.31.2 Clock
          1.        200
          2.        201
        3. 5.3.31.3 System
          1.        203
          2.        204
        4. 5.3.31.4 EFUSE
          1.        206
        5. 5.3.31.5 VMON
          1.        208
      33. 5.3.32 Power
        1.       210
    4. 5.4 Pin Connectivity Requirements
  7. Specifications
    1. 6.1  Absolute Maximum Ratings
    2. 6.2  ESD Ratings
    3. 6.3  Power-On-Hour (POH) Limits
    4. 6.4  Recommended Operating Conditions
    5. 6.5  Operating Performance Points
    6. 6.6  Electrical Characteristics
      1. 6.6.1  I2C, Open-Drain, Fail-Safe (I2C OD FS) Electrical Characteristics
      2. 6.6.2  Fail-Safe Reset (FS Reset) Electrical Characteristics
      3. 6.6.3  HFOSC/LFOSC Electrical Characteristics
      4. 6.6.4  eMMCPHY Electrical Characteristics
      5. 6.6.5  SDIO Electrical Characteristics
      6. 6.6.6  CSI2/DSI D-PHY Electrical Characteristics
      7. 6.6.7  ADC12B Electrical Characteristics
      8. 6.6.8  LVCMOS Electrical Characteristics
      9. 6.6.9  USB2PHY Electrical Characteristics
      10. 6.6.10 SerDes 2-L-PHY/4-L-PHY Electrical Characteristics
      11. 6.6.11 UFS M-PHY Electrical Characteristics
      12. 6.6.12 eDP/DP AUX-PHY Electrical Characteristics
      13. 6.6.13 DDR0 Electrical Characteristics
    7. 6.7  VPP Specifications for One-Time Programmable (OTP) eFuses
      1. 6.7.1 Recommended Operating Conditions for OTP eFuse Programming
      2. 6.7.2 Hardware Requirements
      3. 6.7.3 Programming Sequence
      4. 6.7.4 Impact to Your Hardware Warranty
    8. 6.8  Thermal Resistance Characteristics
      1. 6.8.1 Thermal Resistance Characteristics for ALY Package
      2. 6.8.2 Thermal Resistance Characteristics for AND Package
    9. 6.9  Temperature Sensor Characteristics
    10. 6.10 Timing and Switching Characteristics
      1. 6.10.1 Timing Parameters and Information
      2. 6.10.2 Power Supply Sequencing
        1. 6.10.2.1 Power Supply Slew Rate Requirement
        2. 6.10.2.2 Combined MCU and Main Domains Power- Up Sequencing
        3. 6.10.2.3 Combined MCU and Main Domains Power- Down Sequencing
        4. 6.10.2.4 Isolated MCU and Main Domains Power- Up Sequencing
        5. 6.10.2.5 Isolated MCU and Main Domains Power- Down Sequencing
        6. 6.10.2.6 Independent MCU and Main Domains, Entry and Exit of MCU Only Sequencing
        7. 6.10.2.7 Independent MCU and Main Domains, Entry and Exit of DDR Retention State
        8. 6.10.2.8 Independent MCU and Main Domains, Entry and Exit of GPIO Retention Sequencing
      3. 6.10.3 System Timing
        1. 6.10.3.1 Reset Timing
        2. 6.10.3.2 Safety Signal Timing
        3. 6.10.3.3 Clock Timing
      4. 6.10.4 Clock Specifications
        1. 6.10.4.1 Input and Output Clocks / Oscillators
          1. 6.10.4.1.1 WKUP_OSC0 Internal Oscillator Clock Source
            1. 6.10.4.1.1.1 Load Capacitance
            2. 6.10.4.1.1.2 Shunt Capacitance
          2. 6.10.4.1.2 WKUP_OSC0 LVCMOS Digital Clock Source
          3. 6.10.4.1.3 Auxiliary OSC1 Internal Oscillator Clock Source
            1. 6.10.4.1.3.1 Load Capacitance
            2. 6.10.4.1.3.2 Shunt Capacitance
          4. 6.10.4.1.4 Auxiliary OSC1 LVCMOS Digital Clock Source
          5. 6.10.4.1.5 Auxiliary OSC1 Not Used
        2. 6.10.4.2 Output Clocks
        3. 6.10.4.3 PLLs
        4. 6.10.4.4 Module and Peripheral Clocks Frequencies
      5. 6.10.5 Peripherals
        1. 6.10.5.1  ATL
          1. 6.10.5.1.1 ATL_PCLK Timing Requirements
          2. 6.10.5.1.2 ATL_AWS[x] Timing Requirements
          3. 6.10.5.1.3 ATL_BWS[x] Timing Requirements
          4. 6.10.5.1.4 ATCLK[x] Switching Characteristics
        2. 6.10.5.2  CPSW2G
          1. 6.10.5.2.1 CPSW2G MDIO Interface Timings
          2. 6.10.5.2.2 CPSW2G RMII Timings
            1. 6.10.5.2.2.1 CPSW2G RMII[x]_REF_CLK Timing Requirements – RMII Mode
            2. 6.10.5.2.2.2 CPSW2G RMII[x]_RXD[1:0], RMII[x]_CRS_DV, and RMII[x]_RX_ER Timing Requirements – RMII Mode
            3. 6.10.5.2.2.3 CPSW2G RMII[x]_TXD[1:0], and RMII[x]_TX_EN Switching Characteristics – RMII Mode
          3. 6.10.5.2.3 CPSW2G RGMII Timings
            1. 6.10.5.2.3.1 RGMII[x]_RXC Timing Requirements – RGMII Mode
            2. 6.10.5.2.3.2 CPSW2G Timing Requirements for RGMII[x]_RD[3:0], and RGMII[x]_RCTL – RGMII Mode
            3. 6.10.5.2.3.3 CPSW2G RGMII[x]_TXC Switching Characteristics – RGMII Mode
            4. 6.10.5.2.3.4 RGMII[x]_TD[3:0], and RGMII[x]_TX_CTL Switching Characteristics – RGMII Mode
        3. 6.10.5.3  CSI-2
        4. 6.10.5.4  DDRSS
        5. 6.10.5.5  DSS
        6. 6.10.5.6  eCAP
          1. 6.10.5.6.1 Timing Requirements for eCAP
          2. 6.10.5.6.2 Switching Characteristics for eCAP
        7. 6.10.5.7  EPWM
          1. 6.10.5.7.1 Timing Requirements for eHRPWM
          2. 6.10.5.7.2 Switching Characteristics for eHRPWM
        8. 6.10.5.8  eQEP
          1. 6.10.5.8.1 Timing Requirements for eQEP
          2. 6.10.5.8.2 Switching Characteristics for eQEP
        9. 6.10.5.9  GPIO
          1. 6.10.5.9.1 GPIO Timing Requirements
          2. 6.10.5.9.2 GPIO Switching Characteristics
        10. 6.10.5.10 GPMC
          1. 6.10.5.10.1 GPMC and NOR Flash — Synchronous Mode
            1. 6.10.5.10.1.1 GPMC and NOR Flash Timing Requirements — Synchronous Mode
            2. 6.10.5.10.1.2 GPMC and NOR Flash Switching Characteristics – Synchronous Mode
          2. 6.10.5.10.2 GPMC and NOR Flash — Asynchronous Mode
            1. 6.10.5.10.2.1 GPMC and NOR Flash Timing Requirements – Asynchronous Mode
            2. 6.10.5.10.2.2 GPMC and NOR Flash Switching Characteristics – Asynchronous Mode
          3. 6.10.5.10.3 GPMC and NAND Flash — Asynchronous Mode
            1. 6.10.5.10.3.1 GPMC and NAND Flash Timing Requirements – Asynchronous Mode
            2. 6.10.5.10.3.2 GPMC and NAND Flash Switching Characteristics – Asynchronous Mode
          4. 6.10.5.10.4 GPMC0 IOSET
        11. 6.10.5.11 HyperBus
          1. 6.10.5.11.1 Timing Requirements for HyperBus
          2. 6.10.5.11.2 HyperBus 166 MHz Switching Characteristics
          3. 6.10.5.11.3 HyperBus 100 MHz Switching Characteristics
        12. 6.10.5.12 I2C
        13. 6.10.5.13 I3C
        14. 6.10.5.14 MCAN
        15. 6.10.5.15 MCASP
        16. 6.10.5.16 MCSPI
          1. 6.10.5.16.1 MCSPI — Controller Mode
          2. 6.10.5.16.2 MCSPI — Peripheral Mode
        17. 6.10.5.17 MMCSD
          1. 6.10.5.17.1 MMC0 - eMMC Interface
            1. 6.10.5.17.1.1 Legacy SDR Mode
            2. 6.10.5.17.1.2 High Speed SDR Mode
            3. 6.10.5.17.1.3 High Speed DDR Mode
            4. 6.10.5.17.1.4 HS200 Mode
            5. 6.10.5.17.1.5 HS400 Mode
          2. 6.10.5.17.2 MMC1/2 - SD/SDIO Interface
            1. 6.10.5.17.2.1 Default Speed Mode
            2. 6.10.5.17.2.2 High Speed Mode
            3. 6.10.5.17.2.3 UHS–I SDR12 Mode
            4. 6.10.5.17.2.4 UHS–I SDR25 Mode
            5. 6.10.5.17.2.5 UHS–I SDR50 Mode
            6. 6.10.5.17.2.6 UHS–I DDR50 Mode
            7. 6.10.5.17.2.7 UHS–I SDR104 Mode
        18. 6.10.5.18 CPTS
          1. 6.10.5.18.1 CPTS Timing Requirements
          2. 6.10.5.18.2 CPTS Switching Characteristics
        19. 6.10.5.19 OSPI
          1. 6.10.5.19.1 OSPI0/1 PHY Mode
            1. 6.10.5.19.1.1 OSPI0/1 With PHY Data Training
            2. 6.10.5.19.1.2 OSPI Without Data Training
              1. 6.10.5.19.1.2.1 OSPI Timing Requirements – SDR Mode
              2. 6.10.5.19.1.2.2 OSPI Switching Characteristics – SDR Mode
              3. 6.10.5.19.1.2.3 OSPI Timing Requirements – DDR Mode
              4. 6.10.5.19.1.2.4 OSPI Switching Characteristics – PHY DDR Mode
          2. 6.10.5.19.2 OSPI0/1 Tap Mode
            1. 6.10.5.19.2.1 OSPI0 Tap SDR Timing
            2. 6.10.5.19.2.2 OSPI0 Tap DDR Timing
        20. 6.10.5.20 OLDI
          1. 6.10.5.20.1 OLDI Switching Characteristics
        21. 6.10.5.21 PCIE
        22. 6.10.5.22 Timers
          1. 6.10.5.22.1 Timing Requirements for Timers
          2. 6.10.5.22.2 Switching Characteristics for Timers
        23. 6.10.5.23 UART
          1. 6.10.5.23.1 Timing Requirements for UART
          2. 6.10.5.23.2 UART Switching Characteristics
        24. 6.10.5.24 USB
      6. 6.10.6 Emulation and Debug
        1. 6.10.6.1 Trace
        2. 6.10.6.2 JTAG
          1. 6.10.6.2.1 JTAG Electrical Data and Timing
            1. 6.10.6.2.1.1 JTAG Timing Requirements
            2. 6.10.6.2.1.2 JTAG Switching Characteristics
  8. Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagram
    3. 7.3 Processor Subsystems
      1. 7.3.1 Arm Cortex-A72
      2. 7.3.2 Arm Cortex-R5F
      3. 7.3.3 DSP C71x
    4. 7.4 Accelerators and Coprocessors
      1. 7.4.1 GPU
      2. 7.4.2 VPAC
      3. 7.4.3 DMPAC
    5. 7.5 Other Subsystems
      1. 7.5.1 MSMC
      2. 7.5.2 NAVSS
        1. 7.5.2.1 NAVSS0
        2. 7.5.2.2 MCU_NAVSS
      3. 7.5.3 PDMA Controller
      4. 7.5.4 Power Supply
      5. 7.5.5 Peripherals
        1. 7.5.5.1  ADC
        2. 7.5.5.2  ATL
        3. 7.5.5.3  CSI
          1. 7.5.5.3.1 Camera Streaming Interface Receiver (CSI_RX_IF) and MIPI DPHY Receiver (DPHY_RX)
          2. 7.5.5.3.2 Camera Streaming Interface Transmitter (CSI_TX_IF)
        4. 7.5.5.4  CPSW2G
        5. 7.5.5.5  CPSW9G
        6. 7.5.5.6  DCC
        7. 7.5.5.7  DDRSS
        8. 7.5.5.8  DSS
          1. 7.5.5.8.1 DSI
          2. 7.5.5.8.2 eDP
        9. 7.5.5.9  eCAP
        10. 7.5.5.10 EPWM
        11. 7.5.5.11 ELM
        12. 7.5.5.12 ESM
        13. 7.5.5.13 eQEP
        14. 7.5.5.14 GPIO
        15. 7.5.5.15 GPMC
        16. 7.5.5.16 Hyperbus
        17. 7.5.5.17 I2C
        18. 7.5.5.18 I3C
        19. 7.5.5.19 MCAN
        20. 7.5.5.20 MCASP
        21. 7.5.5.21 MCRC Controller
        22. 7.5.5.22 MCSPI
        23. 7.5.5.23 MMC/SD
        24. 7.5.5.24 OSPI
        25. 7.5.5.25 PCIE
        26. 7.5.5.26 SerDes
        27. 7.5.5.27 WWDT
        28. 7.5.5.28 Timers
        29. 7.5.5.29 UART
        30. 7.5.5.30 USB
        31. 7.5.5.31 UFS
  9. Applications, Implementation, and Layout
  10. Device Connection and Layout Fundamentals
    1. 9.1 Power Supply Decoupling and Bulk Capacitors
      1. 9.1.1 Power Distribution Network Implementation Guidance
    2. 9.2 External Oscillator
    3. 9.3 JTAG and EMU
    4. 9.4 Reset
    5. 9.5 Unused Pins
    6. 9.6 Hardware Design Guide for JacintoTM 7 Devices
  11. 10Peripheral- and Interface-Specific Design Information
    1. 10.1 LPDDR4 Board Design and Layout Guidelines
    2. 10.2 OSPI and QSPI Board Design and Layout Guidelines
      1. 10.2.1 No Loopback and Internal Pad Loopback
      2. 10.2.2 External Board Loopback
      3. 10.2.3 DQS (only available in Octal Flash devices)
    3. 10.3 USB VBUS Design Guidelines
    4. 10.4 System Power Supply Monitor Design Guidelines using VMON/POK
    5. 10.5 High Speed Differential Signal Routing Guidance
    6. 10.6 Thermal Solution Guidance
  12. 11Device and Documentation Support
    1. 11.1 Device Nomenclature
      1. 11.1.1 Standard Package Symbolization
      2. 11.1.2 Device Naming Convention
    2. 11.2 Tools and Software
    3. 11.3 Support Resources
    4. 11.4 Trademarks
    5. 11.5 Electrostatic Discharge Caution
    6. 11.6 Glossary
  13. 12Revision History
  14. 13Mechanical, Packaging, and Orderable Information
    1. 13.1 Packaging Information

Package Options

Refer to the PDF data sheet for device specific package drawings

Mechanical Data (Package|Pins)
  • ALY|1414
Thermal pad, mechanical data (Package|Pins)
Orderable Information

Table 5-5 DDRSS0 Signal Descriptions
SIGNAL NAME [1] ((2))PIN TYPE [2]DESCRIPTION [3]ALY PIN [4]AND PIN [4]
DDR0_CKNIODDRSS Differential Clock (negative)AB2Y2
DDR0_CKPIODDRSS Differential Clock (positive)AC1AA1
DDR0_RESETnIODDRSS Reset AD5W7
DDR0_RETIDDR Retention EnableAC8AC7
DDR0_CA0IODDRSS Command Address AD2AA3
DDR0_CA1IODDRSS Command Address AC5Y4
DDR0_CA2IODDRSS Command Address AB4AA4
DDR0_CA3IODDRSS Command Address AC4AB3
DDR0_CA4IODDRSS Command Address AB3Y3
DDR0_CA5IODDRSS Command Address AC3AB5
DDR0_CAL0 (1)AIO Pad Calibration ResistorAE8R7
DDR0_CKE0IODDRSS Clock EnableAB6AB6
DDR0_CKE1IODDRSS Clock EnableAD3AB7
DDR0_CSn0_0IODDRSS Chip SelectAD7AA6
DDR0_CSn0_1IODDRSS Chip SelectAC7Y5
DDR0_CSn1_0IODDRSS Chip SelectAB7Y7
DDR0_CSn1_1IODDRSS Chip SelectAD6AA7
DDR0_DM0IODDRSS Data MaskV3U6
DDR0_DM1IODDRSS Data MaskAA4V2
DDR0_DM2IODDRSS Data MaskAG2AE2
DDR0_DM3IODDRSS Data MaskAJ5AF6
DDR0_DQ0IODDRSS Data U2R5
DDR0_DQ1IODDRSS Data U4R4
DDR0_DQ2IODDRSS Data W6R2
DDR0_DQ3IODDRSS Data W5T4
DDR0_DQ4IODDRSS Data V4U5
DDR0_DQ5IODDRSS Data V7T3
DDR0_DQ6IODDRSS Data U5T6
DDR0_DQ7IODDRSS Data V6T7
DDR0_DQ8IODDRSS Data Y2V4
DDR0_DQ9IODDRSS Data W3V7
DDR0_DQ10IODDRSS Data AA3W3
DDR0_DQ11IODDRSS Data W2V5
DDR0_DQ12IODDRSS Data AA6W6
DDR0_DQ13IODDRSS Data Y4U2
DDR0_DQ14IODDRSS Data Y5W4
DDR0_DQ15IODDRSS Data AA7U3
DDR0_DQ16IODDRSS Data AF2AD5
DDR0_DQ17IODDRSS Data AE7AC3
DDR0_DQ18IODDRSS Data AG3AE3
DDR0_DQ19IODDRSS Data AF5AB2
DDR0_DQ20IODDRSS Data AE6AC4
DDR0_DQ21IODDRSS Data AF4AD2
DDR0_DQ22IODDRSS Data AE3AC6
DDR0_DQ23IODDRSS Data AE4AD4
DDR0_DQ24IODDRSS Data AG5AG4
DDR0_DQ25IODDRSS Data AH3AG2
DDR0_DQ26IODDRSS Data AJ2AF3
DDR0_DQ27IODDRSS Data AH4AE5
DDR0_DQ28IODDRSS Data AJ4AE6
DDR0_DQ29IODDRSS Data AH6AG5
DDR0_DQ30IODDRSS Data AH7AF4
DDR0_DQ31IODDRSS Data AG6AH6
DDR0_DQS0NIODDRSS Complimentary Data StrobeV1T1
DDR0_DQS0PIODDRSS Data StrobeU1R1
DDR0_DQS1NIODDRSS Complimentary Data StrobeY1W1
DDR0_DQS1PIODDRSS Data StrobeAA1V1
DDR0_DQS2NIODDRSS Complimentary Data StrobeAE1AC1
DDR0_DQS2PIODDRSS Data StrobeAF1AD1
DDR0_DQS3NIODDRSS Complimentary Data StrobeAH1AF1
DDR0_DQS3PIODDRSS Data StrobeAJ1AG1
An external 240 Ω ±1% resistor must be connected between this pin and VSS. No external voltage should be applied to this pin.
DDRSS0, DDRSS1, DDRSS2, and DDRSS3 must always be used in incremental order. For instance, when using a single LPDDR component, it must be connected to the DDR0_* interface. When using two LPDDR components, they must be connected to DDR0_* and DDR1_* interfaces, and so forth.