Hello Camiel,

Hooray, the units and display are correct for your controller for
the non-guide speeds!

Thanks so much for verifying that -- hopefully "set" commands
above 999 will also work. (Those are undocumented at this
point, based on the documents I have.)

On the -1 bug: I haven't tested this, but let's say (for the sake of
the discussion :-) ) that the OTA does indeed end up pointing at
the wrong place, which is a likely outcome. I did a little experiment,
and for the controller commands (or hand controller button presses)
that *move* the position, they do move the position quite happily
into that "forbidden" band. I just can't use any command that
sends coordinates, or an Altitude position (I tried that also).

Please check my knowledge on this, but I *think* that all I have
available to me to correct the position would be the LX200 move
commands, which move in one of the cardinal directions at a
given pace. That pace is the currently-selected "slew" rate
(center, find, slew, goto).

The amount of time would be dependent on the system clock,
and therefore dependent upon the responsiveness of the
system to issuing tty commands at a given interval. This
is because, as far as I know, there is no command to move
for a given period of time (except for pulse guiding, which is
not universally available, and which operates only on the
current guide rate, which is much too slow for the correction).

So, if the target Dec position were in the "forbidden zone",
I would have to detect the end of that slew, then:

1) Pick a rate (e.g., the "find" rate), change it to a known value
(adjusted for distance) and calculate the amount of time necessary
to go twice the distance, or a bit less, to the celestial equator at
that rate;
2) Start that southward motion;
3) At the end of that given time (say, an alert event), issue the
command to stop the motion;
4) Check the current Dec position, and if it is off, go through a
cycle at a slower rate (say, a guide rate) to correct the position.
For this, I *could* use the pulse guide facility if available, and if
not, just cycle for a reasonable time until reasonably close. :-)
5) Return the find rate to its former value.

Even after all this, any command that is issued that specifies
a Dec or altitude position will undo all that good work!

Please let me know if I have completely missed some much
easier way to do this. :blush:

Regards,

Gregory

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