hisl_0044: Configuration Parameters > Diagnostics > Sample Time
R2026bSet sample time diagnostic parameters to error to support robust code generation
Usage: High-Integrity System Modeling
Guideline ID: hisl_0044
Rules
| hisl_0044: Configuration Parameters > Diagnostics > Sample Time |
|---|
In the Configuration
Parameters dialog box, on the Diagnostics > Sample Time pane, set these parameters to
If the target system does not allow
preemption between tasks that have equal priority, set Tasks with equal priority to
Rationale Support generation of robust and unambiguous code. Verification Check safety-related diagnostic settings for sample time (Simulink Check) |
Tips
Enabling diagnostics pertaining to the solver provides information to detect violations of other guidelines.
This table clarifies the result of not specifying the configuration parameter as indicated above.
Configuration Parameter Result Source block specifies -1 sample time Use of inherited sample times for a source block, such as Sine Wave, can go undetected and result in unpredictable execution rates for source and downstream blocks. Multitask data transfer Invalid transfer of data between two blocks operating in multitasking mode can go undetected. You cannot use invalid data transfer for embedded real-time software applications. Multitask conditionally executed subsystems A conditionally executed multirate subsystem, operating in multitasking mode. might go undetected and corrupt data or show unexpected behavior in a target system that allows preemption. Tasks with equal priority Two asynchronous tasks with equal priority might go undetected and show unexpected behavior in target systems that allow preemption. Enforce sample times specified by Signal Specification blocks Inconsistent sample times for a Signal Specification block and the connected destination block might go undetected and result in unpredictable execution rates. Unspecified inheritability of sample times An S-function that is not explicitly set to inherit sample time can go undetected and result in unpredictable behavior.
Industry Standards
DO-331, Section MB.6.3.1.b 'High-level requirements are accurate and consistent'
DO-331, Section MB.6.3.2.b 'Low-level requirements are accurate and consistent'
DO-331, Section MB.6.3.3.b 'Software architecture is consistent'
DO-331, Section MB.6.3.3.e – Software architecture conforms to standards.
IEC 61508-3, Table A.3 (3) 'Language subset'
IEC 62304, 5.5.3 - Software Unit acceptance criteria
ISO 26262-6, Table 1 (1b) 'Use of language subsets'
ISO 26262-6, Table 1 (1f) 'Use of unambiguous graphical representation'
ISO 26262-6, Table 1 (1i) - 'Concurrency aspects'
ISO 26262-6, Table 3 (1i) - 'Appropriate management of shared resources'
EN 50128, Table A.4 (11) 'Language Subset'
EN 50657, Table A.4 (11) 'Language Subset'