Variable length data in Commands/Telemetry

[Peet, Sterling L]

   Is there a method to send variable length arguments in commands and telemetry (events, I guess)?  I realize that I could load up Fw::Buf in a component byte by byte with a command, but that seems tedious with lots of overhead.

   I think I want something between the file uplink/downlink full message suite, and single byte transfer.  I want to send arbitrary bytes to a component from the GDS, and get back arbitrary bytes.  The order, start, and end all matter.  In some senses it is a file but its only a few bytes to low tens of bytes in length for either direction.

   I looked through the documentation for stuff like serializables as command arguments, but didn’t find anything.  Maybe I didn’t look in the correct place?

Thanks,

Sterling Peet

Space Systems Design Lab at Aerospace Engineering
Engineering Science and Mechanics Building
Georgia Institute of Technology
620 Cherry St. N.W. Atlanta GA 30332

Web: http://ssdl.gatech.edu/sterling-peet
Ph: (404) 385-7641

[lestarch]

Is is arbitrary bytes or string text bytes?  You can use string commands to send strings (look at CMD_NO_OP_STRING).  Alternatively, you could use `Fw::Buffer` and hook the file uplink/downlink ports to a component that processes those.

As it stands currently, I don't know that the GDS can send arbitrary byte strings as part of a command.

-Michael

[Peet, Sterling L]

    This is for arbitrary bytes in an exerciser component within a testing deployment.  Since the uplink direction is generally only a handful of bytes, I am currently loading a buffer one byte per command by specifying a value and an index.  Then I send a separate command to run the internal transaction, and downlink the results as multiple events holding a start index and 8 bytes of data each.

    If it was for a flight type context, I would probably consider using a separate messaging protocol and route it to the appropriate component with a custom ground interface component implementation.  Mostly I was looking to see if there was an easier way to leverage the command messages than what I described above.

Thanks,

Sterling Peet

Space Systems Design Lab at Aerospace Engineering
Engineering Science and Mechanics Building
Georgia Institute of Technology
620 Cherry St. N.W. Atlanta GA 30332

Web: http://ssdl.gatech.edu/sterling-peet
Ph: (404) 385-7641

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