A further thought - does SL have the means to open a pipe and
read raw samples from it?   A popen() system call?

If so, a more general interface is possible.  SL could open a
pipe to a script on the PC.  The script makes an ssh connection
to the Pi and invokes some arbitrary command, perhaps a vtread
command to retrieve historic signal.  The command runs on the
Pi and its output arrives at SL through the pipe.

--
Paul Nicholson
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