[Hamlib-developer] Re: Hamlib and rotators

[Francois R. <fgr...@su...>]

Hello Stephane,

>
> Hmm, the protocol looks simple, but I don't understand why the hell there
> are frequencies and modes to be specified when controlling the rotator.
> Do you have a clue?

The spec was invented by the author of WiSP. WiSP is a PacSat ground 
station program (for Windows).   It includes rotator control, radio 
dopler control and PacSat mailbox functions amongst others.  That is 
why there is both radio and rotator stuff.
 
> Some examples of the EASYCOMM II protocol would help also.
> Maybe you are the right person to implement these backends, and test it
> while you're at it.

I will check-out a fresh copy of the CVS and start hacking.  
Should I create a new directory for rotor backends?

> > The basic capabilities of a rotator will be:
> >
> > Movement range and mode:  Minimum and maximum values of the two axis,
> >       and also where the turn-around point is.
> >         (0-180, 0-360, 180-0-180 or 360-0-360, etc.)
> 
> Hmm, I'm sorry, I don't understand why we need a turn-around point.
> Let's say we have min_elevation/max_el and min_az/max_az, all
> being angles relative to horizon / north. Shouldn't it be enough?
> Or did I miss something?

On second thought, the min/max should be enough. Let's keep it simple 
for a start.

> Another question. If I'm not mistaken, there are rotator controllers and
> rotators being controlled. And a given rotator model can be controlled by
> different models of controllers. So, do you think Hamlib should have a
> database of rotator capabilities on top of the backends (which are for
> controllers) ?

Hmm, not sure, will think about it.  Will get back to you on this one.

> exactly! I've done some work on the rpcrig. Works better, still not
> complete (esp. caps retrieval). Right now, I'm testing "rpc.rigd -vvv"
> setup for use with dummy backend, and "rigctl -vvvv -m  1901 -r localhost"
> in another window.
> Seems okay, please let me know how it goes on your side.

As soon as I looked at the rotator backend stuff, I will check
the RPC.


I have a problem with the current CVS code.  The test programs in the
hamlib CVS works fine.  But when I try to link it to a test program 
(external to hamlib), it complain about:
/usr/local/lib/libhamlib.so: undefined reference to
'lt_preloaded_symbols'

I get the same problem with the AC_LIB_HAMLIB macro.  The problem 
started after the hamlib-1.1.2 release.


Cheers
  Francois Retief

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