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nasa / cFE

The Core Flight System (cFS) Core Flight Executive (cFE)
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Incorrect SCID field length #20

Closed CutrightD closed 4 years ago

CutrightD commented 5 years ago

cfe_mission_cfg.h shows a note circa line 49 that 'CCSDS allocates 8 bits for this field in the standard VCDU'. Newer CCSDS versions actually allocate 10-bits for this field - this seems like a minor thing but could potentially have implications elsewhere in the code. Per @acudmore , maybe TO, DS, and CF?

skliper commented 5 years ago

Note fsw/mission_inc/cfe_mission_cfg.h is only used in the deprecated classic build. CMake uses the mission configuration in the top level sample_defs, which is typically copied from the cFE/cmake directory.

https://github.com/nasa/cFE/blob/8811c92094512975e14fd545df355705141560b2/cmake/sample_defs/sample_mission_cfg.h#L47-L50

only real reference is from CFE_SB_SetMsgId:

https://github.com/nasa/cFE/blob/8811c92094512975e14fd545df355705141560b2/fsw/cfe-core/src/sb/cfe_sb_msg_id_util.c#L208

Structure is defined as:

https://github.com/nasa/cFE/blob/8811c92094512975e14fd545df355705141560b2/fsw/cfe-core/src/inc/ccsds.h#L140-L154

And write implemented as:

https://github.com/nasa/cFE/blob/8811c92094512975e14fd545df355705141560b2/fsw/cfe-core/src/inc/ccsds.h#L353-L354

and copies all 16 bits, so no impact to cFE. Could update/remove the 8 bit field comment.

Any impacts to TO, DS, or CF would need to be addressed in their repos (not a cFE issue).

skliper commented 4 years ago

No change applicable to cFE, closing ticket here.