Khalid replied to the topic 'Driver OnStep (LX200 like) for INDI' in the forum. 3 weeks ago

Because INDI is very chatty, sending lots of commands every poll interval, it may uncover things that would not be uncovered using another OnStep client.

I have no intelligent comment to add other than there are significant differences between 4.x and X.

For GX90, OnStepX does the following:
sprintF(reply, "%0.2f", rateSelectToRate(settings.pulseRateSelect));

While 4.x does:

dtostrf(guideRates[currentPulseGuideRate]/15.0,2,2,reply); boolReply=false; break;// pulse-guide rate

For GX96, OnStepX does the following:

case '6': reply[0] = "EWB"[preferredPierSide - 10]; reply[1] = 0; break; // preferred pier side

While 4.x does:

if (preferredPierSide == EAST) strcpy(reply,"E"); else
if (preferredPierSide == WEST) strcpy(reply,"W"); else strcpy(reply,"B");


Khalid replied to the topic 'Driver OnStep (LX200 like) for INDI' in the forum. 3 weeks ago

OnStepX is still really far away from being usable. Last time I tried it (a few months ago), it did not even compile. Howard made changes and it did compile, but did not work at all. Motors did not move.

That is on the S6, which is not the platform that Howard is using for development.

But as long as things are in flux, I would not bother with it.

Join the onstep-dev sub group and report what you find there. It is where Howard responds for OnStepX stuff.


In the Online Configuration Generator select "STM32 Blue Pill".

Note that you have to use a different board manager in the Arduino IDE.

The details are here

Ask on the OnStep mailing list if you have further questions.


Attach a picture of the board that you have and I will verify if it is an STM32 Blue Pill, or something else.

If you know the values to enter into the Online Configuration Generator, then there are very little risks. You will need to reenter a few things after you first power up OnStep (e.g. latitude and longitude, horizon and overhead limits, and maybe backlash if you have it), but after that, it should be smooth.

If you do upgrade to 4.24, and you have a WiFi module, then you need to upgrade it with the SmartWebSever (SWS) too.


The configuration file format has changed so much since 2.x.

The best way to convert is to take the values from your old configuration, and enter them in my Online Configuration Generator which is at

You will then get a Config.h that you can compile.


Regarding OnStep 2.2, it is quite ancient now.
I really recommend that you upgrade to 4.24.

The fixes in this thread are already in Jasem's PPA repository packages. So if Astroberry points to this repo, you should get them when you upgrade.


The pull request was merged by Jasem into INDI's repository.

We are now waiting for the PPA packages that incorporates the fixes for OnStep.



This topic is specific to the OnStep telescope controller, and affects far more than just the meridian flip.

For the meridian flip with OnStep, it is a frequently asked question, so we added it to the FAQ page on OnStep's Wiki.

I see that your mount is an iOptron. No idea if any (or all) of that applies to iOptron or not.


Thank you for your persistence. It paid off fixing this bug.

Let us all know when it is accepted by Jasem, so we look for the next indi-bin build.


Please update the pull request to include the attached code.
It is the same functionality as yours, but minus the Windows vs. Linux line ending (carriage return removed).
Also, the comments are in the correct place (on the condition line), so easier to read.


I tested the file you posted. I had to massage it to remove carriage returns.

It behaves normally on 4.x:
- The target in Ekos is now the star that is being slewed to, even though the slew is still in progress. It is no longer the previous star.
- The popup notification that the mount has reached the target only happens when the slew has actually ended.
- The 'Eq. Coordinates' in INDI goes yellow when the slew is in progress, and then green when the slew ended.

So all good on my side.

We need this to go into INDI's repo quickly, because it affects lots of people, not just those who do meridian flips.

Do you want me to submit it to Jasem?