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A while back I was on a project to port a satellite simulator from SPARC/Solaris to RHEL/x64. The compressed telemetry stream that came from the satellite need

by jcadam 5y ago

A while back I was on a project to port a satellite simulator from SPARC/Solaris to RHEL/x64. The compressed telemetry stream that came from the satellite needed to be in big endian (and that's what the ground station software expected), and the simulator needed to mimic the behavior. This was not a problem for the old SPARC system, which naturally put everything in the correct order without any fuss, but one of the biggest sticking points in porting over to x64 was having to now manually pack all of that binary data. Using Ada, (what else!) of course.

metiscus 5y ago
If memory serves correctly, ada 2012 and beyond has language level support for this. I was working on porting some code from an aviation platform to run on PC and it was all in ada 2005 so we didn't have the benefit of that available.
- jcadam 5y ago
  Same here, Ada2005 for the port. The simulator was originally written in Ada95. Part of what made it even less fun was the data was highly packed and individual fields crossed byte boundaries (these 5 bits are X, the next 4 bits are Y, etc.) :(
  - bombcar 5y ago
    Given enough memory it may be worth treating the whole stream internally as a bitstream.
  - onox 5y ago
    Couldn't you add the Bit_Order and Scalar_Storage_Order attributes (or aspects in Ada 2012) to your records/arrays? Or did Scalar_Storage_Order not exist at the time?