Lookup Table Blocks

hisl_0033: Usage of Lookup Table blocks

ID: Titlehisl_0033: Usage of Lookup Table blocks
Description

To support robustness of generated code, when using the 1-D Lookup Table, 2-D Lookup Table, n-D Lookup Table, Prelookup, and Interpolation Using Prelookup blocks:

A

Clear block parameter Remove protection against out-of-range input in generated code in each 1-D Lookup Table, 2-D Lookup Table, n-D Lookup Table, or Prelookup block.

B

Clear block parameter Remove protection against out-of-range index in generated code in each Interpolation Using Prelookup block.

Note

If the lookup table inputs are not guaranteed to fall within the range of valid breakpoint values, exclusion of range-checking code may produce unexpected results.

RationaleA,B

Protect against out-of-range inputs or indices.

Model Advisor Checks
  • By Task > Modeling Standards for DO-178C/DO-331 > High-Integrity Systems > Simulink > Check usage of lookup table blocks

  • By Task > Modeling Standards for IEC 61508 > High-Integrity Systems > Simulink > Check usage of lookup table blocks

  • By Task > Modeling Standards for IEC 62304 > High-Integrity Systems > Simulink > Check usage of lookup table blocks

  • By Task > Modeling Standards for EN 50128 > High-Integrity Systems > Simulink > Check usage of lookup table blocks

  • By Task > Modeling Standards for ISO 26262 > High-Integrity Systems > Simulink > Check usage of lookup table blocks

For check details, see Check usage of lookup table blocks (Simulink Check).

References
  • DO-331, Sections MB.6.3.1.g and MB.6.3.2.g 'Algorithms are accurate'

  • IEC 61508-3, Table A.3 (3) 'Language subset’
    IEC 61508-3, Table A.4 (3) 'Defensive programming’

  • IEC 62304, 5.5.3 - Software Unit acceptance criteria

  • ISO 26262-6, Table 1 (1b) 'Use of language subsets'
    ISO 26262-6, Table 1 (1d) 'Use of defensive implementation techniques'

  • EN 50128, Table A.4 (11) 'Language Subset'
    EN 50128, Table A.3 (1) 'Defensive Programming'

Last ChangedR2017b