FindHome() implementation issue in the OnStep ASCOM driver

I have an issue with the homing ASCOM implementation in OnStep.

The FindHome() method definition changed between V3 and V4 telescope implementation.
The V3 FindHome() method only returns when the mount has found home, whereas the latest V4 method call is asynchronous, returning immediately, and has to set the slewing property true whilst it is homing. When it is homed, AtHome is set true and slewing set false.

The OnStep ASCOM driver is returning immediately from a FindHome() method call, but it is not setting Slewing to True. This is causing confusion with imaging applications, which monitor slewing property and assume homing is complete before it has found the sensors.

The best solution is to have the driver set slewing=true while homing. One could return from FindHome() after finding home but it is not preferred as it is the old standard.

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Howard has released a change to the ASCOM driver. Until ASCOM 7 is more fully established, he will adopt the V3 standard, returning from the call when it has homed, or raising an exception after 4 mins if it hasn’t.

Does this resolve the issue of the scope not searching for home when slewing large distances?

I have not explicitly tested, but assume not.

Gustavo - I would also hold off the change (1.0.41). I was testing it earlier and it has a bug which causes it to report the guide rates = 0 , an illegal value, and causes PHD2 to fail. Hopefully another one tomorrow.

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10.0.42 has been released - it should fix both the FindHome anomaly in 10.0.40 and the GuideRate one too, introduced in 10.0.41.
Gustavo - for homing, I developed a simple script that replaces a home and park instruction sequence in NINA. It homes twice - so it should overcome slews of over 90 degrees. Let me check out the new ASCOM driver and I can share if you want it. (You could also do this in NINA, too;

unpark
tracking on
delay 5s
home
tracking on
delay 5s
home
tracking on
delay 5s
park

best
Chris

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ASCOM 1.0.42 has been released, making it unnecessary for workarounds in NINA. This version returns from FindHome() when it is complete and reports the guide rates correctly for apps like PHD2 to use.