SFFS889 July   2024 TMS320F2800132 , TMS320F2800133 , TMS320F2800135 , TMS320F2800137

 

  1.   1
  2.   Trademarks
  3. 1Introduction
  4. 2TMS320F280013x Hardware Component Functional Safety Capability
  5. 3TI Development Process for Management of Systematic Faults
    1. 3.1 TI New-Product Development Process
    2. 3.2 TI Functional Safety Development Process
  6. 4Component Overview
    1. 4.1 Targeted Applications
      1. 4.1.1 TMS320F280013x MCU
    2. 4.2 Hardware Component Functional Safety Concept
      1. 4.2.1 TMS320F280013x MCU Safety Features
      2. 4.2.2 Fault Tolerant Time Interval (FTTI)
      3. 4.2.3 TMS320F280013x MCU Safe State
      4. 4.2.4 Operating States
    3. 4.3 Hardware Component Configuration
      1. 4.3.1 Assumptions of Use - F280013x Self-Test Libraries
      2. 4.3.2 Operational Details - SDL
        1. 4.3.2.1 Operational Details – SDL Module Mapping
    4. 4.4 TMS320F280013x MCU Safety Implementation
      1. 4.4.1 Assumptions of Use
      2. 4.4.2 Example Safety Concept Implementation Options on TMS320F280013x MCU
  7. 5Description of Safety Elements
    1. 5.1 TMS320F280013x MCU Infrastructure Components
      1. 5.1.1 Power Supply
      2. 5.1.2 Clock
      3. 5.1.3 APLL
      4. 5.1.4 Reset
      5. 5.1.5 System Control Module and Configuration Registers
      6. 5.1.6 JTAG Debug, Trace, Calibration, and Test Access
    2. 5.2 Processing Elements
      1. 5.2.1 C28x Central Processing Unit (CPU)
    3. 5.3 Memory (Flash, SRAM and ROM)
      1. 5.3.1 Embedded Flash Memory
      2. 5.3.2 Embedded SRAM
      3. 5.3.3 Embedded ROM
    4. 5.4 On-Chip Communication Including Bus Arbitration
      1. 5.4.1 Device Interconnect
      2. 5.4.2 Enhanced Peripheral Interrupt Expander (ePIE) Module
      3. 5.4.3 Dual Zone Code Security Module (DCSM)
      4. 5.4.4 Crossbar (X-BAR)
      5. 5.4.5 Timer
    5. 5.5 Digital I/O
      1. 5.5.1 General-Purpose Input/Output (GPIO) and Pinmuxing
      2. 5.5.2 Enhanced Pulse Width Modulators (ePWM)
      3. 5.5.3 High Resolution PWM (HRPWM)
      4. 5.5.4 Enhanced Capture (eCAP)
      5. 5.5.5 Enhanced Quadrature Encoder Pulse (eQEP)
      6. 5.5.6 External Interrupt (XINT)
    6. 5.6 Analog I/O
      1. 5.6.1 Analog-to-Digital Converter (ADC)
      2. 5.6.2 Comparator Subsystem (CMPSS)
    7. 5.7 Data Transmission
      1. 5.7.1 Controller Area Network (DCAN)
      2. 5.7.2 Serial Peripheral Interface (SPI)
      3. 5.7.3 Serial Communication Interface (SCI)
      4. 5.7.4 Inter-Integrated Circuit (I2C)
  8. 6Management of Random Faults
    1. 6.1 Fault Reporting
      1. 6.1.1 Suggestions for Improving Freedom From Interference
      2. 6.1.2 Suggestions for Addressing Common Cause Failures
    2. 6.2 Functional Safety Mechanism
    3. 6.3 Description of Functional Safety Mechanisms
      1. 6.3.1 TMS320F280013x MCU Infrastructure Components
        1. 6.3.1.1  Clock Integrity Check Using DCC
        2. 6.3.1.2  Clock Integrity Check Using CPU Timer
        3. 6.3.1.3  Clock Integrity Check Using HRPWM
        4. 6.3.1.4  EALLOW Protection for Critical Registers
        5. 6.3.1.5  External Monitoring of Clock via XCLKOUT
        6. 6.3.1.6  External Monitoring of Warm Reset (XRSn)
        7. 6.3.1.7  External Voltage Supervisor
        8. 6.3.1.8  External Watchdog
        9. 6.3.1.9  Glitch Filtering on Reset Pins
        10. 6.3.1.10 Hardware Disable of JTAG Port
        11. 6.3.1.11 Lockout of JTAG Access Using OTP
        12. 6.3.1.12 Internal Watchdog (WD)
        13. 6.3.1.13 Lock Mechanism for Control Registers
        14. 6.3.1.14 Missing Clock Detect (MCD)
        15. 6.3.1.15 NMIWD Reset Functionality
        16. 6.3.1.16 NMIWD Shadow Registers
        17. 6.3.1.17 Multi-Bit Enable Keys for Control Registers
        18. 6.3.1.18 Online Monitoring of Temperature
        19. 6.3.1.19 Periodic Software Read Back of Static Configuration Registers
        20. 6.3.1.20 Peripheral Clock Gating (PCLKCR)
        21. 6.3.1.21 Peripheral Soft Reset (SOFTPRES)
        22. 6.3.1.22 Software Test of Reset - Type 1
        23. 6.3.1.23 PLL Lock Profiling Using On-Chip Timer
        24. 6.3.1.24 Reset Cause Information
        25. 6.3.1.25 Software Read Back of Written Configuration
        26. 6.3.1.26 Software Test of ERRORSTS Functionality
        27. 6.3.1.27 Software Test of Missing Clock Detect Functionality
        28. 6.3.1.28 Software Test of Watchdog (WD) Operation
        29. 6.3.1.29 Dual-Clock Comparator (DCC) - Type 2
        30. 6.3.1.30 PLL Lock Indication
        31. 6.3.1.31 Software Test of DCC Functionality Including Error Tests
        32. 6.3.1.32 Software Test of PLL Functionality Including Error Tests
        33. 6.3.1.33 Interleaving of FSM States
        34. 6.3.1.34 Brownout Reset (BOR)
      2. 6.3.2 Processing Elements
        1. 6.3.2.1 CPU Handling of Illegal Operation, Illegal Results, and Instruction Trapping
        2. 6.3.2.2 Stack Overflow Detection
        3. 6.3.2.3 CRC Check of Static Memory Contents
      3. 6.3.3 Memory (Flash, SRAM and ROM)
        1. 6.3.3.1  Bit Multiplexing in Flash Memory Array
        2. 6.3.3.2  Bit Multiplexing in SRAM Memory Array
        3. 6.3.3.3  Data Scrubbing to Detect/Correct Memory Errors
        4. 6.3.3.4  Flash ECC
        5. 6.3.3.5  Flash Program Verify and Erase Verify Check
        6. 6.3.3.6  Flash Program/Erase Protection
        7. 6.3.3.7  Flash Wrapper Error and Status Reporting
        8. 6.3.3.8  Prevent 0 to 1 Transition Using Program Command
        9. 6.3.3.9  On-Demand Software Program Verify and Blank Check
        10. 6.3.3.10 CMDWEPROT* and Program Command Data Buffer Registers Self-Clear After Command Execution
        11. 6.3.3.11 ECC Generation and Checker Logic is Separate in Hardware
        12. 6.3.3.12 Auto ECC Generation Override
        13. 6.3.3.13 Software Test of ECC Logic
        14. 6.3.3.14 Software Test of Flash Prefetch, Data Cache, and Wait-States
        15. 6.3.3.15 Access Protection Mechanism for Memories
        16. 6.3.3.16 SRAM ECC
        17. 6.3.3.17 SRAM Parity
        18. 6.3.3.18 Software Test of Parity Logic
        19. 6.3.3.19 Software Test of SRAM
        20. 6.3.3.20 Memory Power-On Self-Test (MPOST)
        21. 6.3.3.21 ROM Parity
      4. 6.3.4 On-Chip Communication Including Bus-Arbitration
        1. 6.3.4.1 1oo2 Software Voting Using Secondary Free Running Counter
        2. 6.3.4.2 Maintaining Interrupt Handler for Unused Interrupts
        3. 6.3.4.3 Power-Up Pre-Operational Security Checks
        4. 6.3.4.4 Majority Voting and Error Detection of Link Pointer
        5. 6.3.4.5 Software Check of X-BAR Flag
        6. 6.3.4.6 Software Test of ePIE Operation Including Error Tests
      5. 6.3.5 Digital I/O
        1. 6.3.5.1  eCAP Application Level Safety Mechanism
        2. 6.3.5.2  ePWM Application Level Safety Mechanism
        3. 6.3.5.3  ePWM Fault Detection Using X-BAR
        4. 6.3.5.4  ePWM Synchronization Check
        5. 6.3.5.5  eQEP Application Level Safety Mechanism
        6. 6.3.5.6  eQEP Quadrature Watchdog
        7. 6.3.5.7  eQEP Software Test of Quadrature Watchdog Functionality
        8. 6.3.5.8  Hardware Redundancy
        9. 6.3.5.9  HRPWM Built-In Self-Check and Diagnostic Capabilities
        10. 6.3.5.10 Information Redundancy Techniques
        11. 6.3.5.11 Monitoring of ePWM by eCAP
        12. 6.3.5.12 Monitoring of ePWM by ADC
        13. 6.3.5.13 Online Monitoring of Periodic Interrupts and Events
        14. 6.3.5.14 Software Test of Function Including Error Tests
        15. 6.3.5.15 QMA Error Detection Logic
      6. 6.3.6 Analog I/O
        1. 6.3.6.1 ADC Information Redundancy Techniques
        2. 6.3.6.2 ADC Input Signal Integrity Check
        3. 6.3.6.3 ADC Signal Quality Check by Varying Acquisition Window
        4. 6.3.6.4 CMPSS Ramp Generator Functionality Check
        5. 6.3.6.5 DAC to ADC Loopback Check
        6. 6.3.6.6 Opens/Shorts Detection Circuit for ADC
        7. 6.3.6.7 Disabling Unused Sources of SOC Inputs to ADC
      7. 6.3.7 Data Transmission
        1. 6.3.7.1  Information Redundancy Techniques Including End-to-End Safing
        2. 6.3.7.2  Bit Error Detection
        3. 6.3.7.3  CRC in Message
        4. 6.3.7.4  DCAN Acknowledge Error Detection
        5. 6.3.7.5  DCAN Form Error Detection
        6. 6.3.7.6  DCAN Stuff Error Detection
        7. 6.3.7.7  Software Test of Function Including Error Tests Using EPG
        8. 6.3.7.8  I2C Access Latency Profiling Using On-Chip Timer
        9. 6.3.7.9  I2C Data Acknowledge Check
        10. 6.3.7.10 Parity in Message
        11. 6.3.7.11 SCI Break Error Detection
        12. 6.3.7.12 Frame Error Detection
        13. 6.3.7.13 Overrun Error Detection
        14. 6.3.7.14 Software Test of Function Using I/O Loopback
        15. 6.3.7.15 SPI Data Overrun Detection
        16. 6.3.7.16 Transmission Redundancy
  9.   A Summary of Safety Features and Diagnostics
  10.   B References

6.3.5.10 Information Redundancy Techniques

Information redundancy techniques can be applied through software as an additional runtime diagnostic. To provide diagnostic coverage for network elements outside the TMS320F280013x MCU (wiring harness, connectors, transceiver) end-to-end safety mechanisms are applied. These mechanisms can also provide diagnostic coverage inside the TMS320F280013x MCU.

In the case of processing elements (CPU), this refers to multiple executions of the code and software based cross checking to verify correctness. The multiple execution and result comparison can be based on either the same code executed multiple times or the implementation of diversified software code. For details regarding the implementation, see the ISO 26262-5:2018, D.2.3.4.

Typical control applications involve measuring three-phase voltage and current. These values are either sampled directly using the on chip ADC or sent to the TMS320F280013x MCU by external sensors, which are captured using eCAP, and so forth. In such scenarios, the correlation between input signals can be used to check the integrity (for example, if the three phase voltage, V1, V2, V3 is being measured, the function V1 + V2 + V3 = 0 can be used to provide diagnostic coverage for input signal integrity).

In the case of SRAM and flash memory, critical data, program, variables, and so forth can be stored redundantly and compared before use. Care must be taken to avoid compiler optimizing code containing redundant data and programs. Safety programs in flash can be copied to SRAM and executed after performing a CRC check against a pre-calculated golden CRC value.