System FDAL and software level are determined

System certification plan is released

PSAC is released

SDP is released

Software requirements standards are released

System requirements are mature enough to begin decomposition

Document high-level software requirements (in SWRD) from the SRD for requirements allocated to software

Identify requirements that have a safety impact (tag with safety attribute)

Identify any derived software requirements (requirements that do not trace to SRD and that define implementation details) and provide rationale for why each one is needed

Develop bidirectional traceability between SRD and SWRD requirements

Include interfaces/interactions in SWRD as needed

Include reference to hardware data in SWRD, as applicable

Document any deviations from requirements standards and obtain SQA approval

Document robustness requirements (tag as robust)

Review SWRD using the company procedures defined in the SVP and make updates as needed

Validate derived requirements (as part of the review) to ensure they are the right requirements (correct and complete)

Involve safety personnel in the review of all derived requirements

Document the development environment in the SLECI

SRD is released and under CM

SWRD is reviewed, updated, released, and under CM

Derived high-level software requirements are reviewed by appropriate safety personnel

SLECI is drafted and under CM

PSAC is released

SDP is released

Software design standards are released

SRD and SWRD are mature enough to begin design

Document low-level requirements using SRD, SWRD, and other referenced requirements as input

Identify interfaces/interactions in SDD as needed

Identify any derived low-level requirements (requirements that do not trace to SWRD and that are implementation details) and provide rationale for why each requirement is needed

Document robustness requirements (tag as robust)

Validate derived requirements (as part of the review) to ensure they are the right requirements (that is, they are correct and complete) (see SVP for details on the review)

Develop bidirectional traceability between high-level requirements and low-level requirements

Develop software architecture to be consistent with the requirements

Review the SDD using the process defined in the SVP and make needed updates

Document any deviations from design standards and obtain SQA approval

Involve safety personnel in the review of all derived requirements

SDD (including low-level requirements and architecture) reviewed, updated, released, and under CM

SRD and SWRD released and under CM

Derived low-level requirements reviewed by appropriate system safety personnel

PSAC is released

SDP is released

Code standards are released

SWRD and SDD are available and mature enough to begin coding

Write code using the SWRD, SDD, SDP, and coding standards as input

Develop bidirectional traceability between the code and low-level requirements

Review code and update based on comments (see SVP for details of the review)

Document any deviations from code standards and obtain SQA approval

Develop and review SCI

Code is reviewed, updated, released, and under CM

SRD, SWRD and SDD are released and under CM

SCI is reviewed and under CM

Code available

SCI drafted

Compiler and linker options are identified in SLECI

Develop build procedures (in SCI) and have an independent person run the procedures for repeatability

Build code, using the build procedures

Prior to formal testing, compile and link the released code, using the approved build procedures (in SCI)

Develop the load procedures (in SCI) and have an independent person run the procedures for repeatability

Update and review SCI (including build and load procedures)

Update (if needed) and review SLECI (prior to formal build of code)

Code is released and under CM

SCI (including build procedures and load procedures) and SLECI are reviewed, released, and under CM

Released code is compiled and linked

Executable object code is released and under CM