PHD not sharing com port with planetarium software

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Allen Force

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Apr 18, 2020, 2:00:47 PM4/18/20
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I didn't use to have this problem but something has changed somewhere.  I'm trying to connect to an iOptron ZEQ mount.  The connection goes from the USB port to a usb-to-serial adapter to an iOptron cable to an RJ connection on the hand controller (Got2Nova) for the ZEQ.

1)  If I connect the planetarium software to the mount it works fine.  When I next try to connect with PHD2 (V2.6.7) it gives the message "Cannot connect to com port".  It then shows a status bar for trying to connect, which eventually times out with the message "ASCOM driver problem during connection.  The operation was cancelled." 
2)  If I connect PHD2 first, it also works fine.  But when I try to connect to the planetarium software it also "Cannot connect to com port".

I have tried this with Cartes du Ciel, Stellarium and an old copy of TheSky6.  I have reinstalled the iOptron ASCOM driver several times.  I started with ASCOM platform 6.3 and upgraded it to 6.4.  I have used 3 different computers.  I have tried multiple USB cables and two different usb-to-serial adapters and two different iOptron cables.  The only thing I haven't replaced is the hand controller.  This has been going on for some time.  I can still image, the only thing I miss out on is being able to use my computer to GOTO, I have to use the hand controller which means I have to be at the mount.  All three computers are Windows 10 and like I said in the beginning, I used to be able to connect and use both at the same time.

I hope that someone out there has an answer for this.  Has anyone else experienced this?

Al

Jack Thewlis

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Apr 18, 2020, 2:17:00 PM4/18/20
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An RS232 COM port operates with as single send/receive system. You can't run two softwares through the same COM port symultaneously.. Having said that, some COM post sockets have dual channel wiring. For example, my Meade LX200 classic does exactly what you are trying to do. However, they still use different port assignments (COM2 and COM3 for example).
Cheers,
Jack

Patrick Chevalley

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Apr 18, 2020, 2:45:32 PM4/18/20
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As Jack say the COM port itself cannot be shared by multiple application.

The telescope sharing must be done at a higher level, at the ASCOM driver level.
But there is a number of condition to make it work correctly.
- All the application must run with the same user, no application can run as administrator.
- More chance it work if all the application use the same architecture 32 or 64 bit.
- The driver must support multiple connection,  if not you can use an intermediary hub, like Poth or the Ascom device hub.

Patrick




Brian Valente

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Apr 18, 2020, 3:34:44 PM4/18/20
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I'm wondering if you are connecting via ascom to your planetarium software? it needs to say ascom driver.

if you are connecting via another way (typically serial) then the planetarium software is not sharing. that is the purpose of ASCOM



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Brian Valente

Allen Force

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Apr 18, 2020, 6:56:22 PM4/18/20
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I know it can be done because I used to have it working for me.  I can connect using the old Poth hub and Cartes du Ciel works and PHD2 says it's connected but but I'm not sure it will really work.  I'm not clear on the ASCOM device hub.I Googled it and found some info on GitHub but don't see anything on the ASCOM site.  Is this something that I would have to download and install?  I used to use Poth with PHD2 and TheSky6 all sorts of experts kept telling me that it wouldn't work.  Then something changed somewhere and it stopped working but I was still able to use them both at the same time.  I had experts telling that couldn't work too.  My guess is that Windows pushed an upgrade that made some change somewhere, possibly a DLL got changed and affect ASCOM.  I'm not running anything as administrator.  Both Cartes du Ciel and Stellarium are 64 bit but ASCOM, PHD2 and TheSky6 are all in Program Files (x86).  I'm connecting to everything using ASCOM. We're having a bit of weather here so I won't be able to test using Poth until next week but if you know how I can access the ASCOM Device Hub please let me know.

Al

Brian Valente

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Apr 18, 2020, 7:00:11 PM4/18/20
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Hi Al,

if you can stick with Stellarium, you can download the latest version that has ascom built in. 

you can get it here: http://stellarium.org/

once you do that, you can go into the settings and to telescope, enable on load, and then use the ascom driver

just to be clear, this isn't about PHD sharing or not sharing. If you are using the planetarium program and connecting directly to the camera (not via ascom driver or an ascom hub) it will block *any* program from using it. 

Make sure you have the ascom driver for your camera installed as well

Give stellarium a try

Brian

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Allen Force

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Apr 19, 2020, 12:00:28 PM4/19/20
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Thanks Brian,

I was using the latest Stellarium, unless there's something newer than a week.  The camera is not an issue for PHD2.  I connect directly to it with USB.  However I had been using a 64bit version of Stellarium, installed in c:\Program Files and ASCOM and PHD2 are in c:\Program Files (x86).  I attempted to install a 32 bit version but it wanted to install in the same place so I stopped it.  I just checked again and downloaded from another source (declining a lot of junkware that wanted to come with it) and it did install in the right place.  I'll try and test it this evening.  Wish me luck.

Al

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Allen Force

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Apr 21, 2020, 9:06:32 AM4/21/20
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OK I got the 32 bit Stellarium installed and working but I still can't connect to both PHD2 and the planetarium software at the same time.  I also tried POTH and that didn't work either.  It looks like my last hope is the ASCOM Device Hub.  I've been able to download the files from Github and also a PDF for how to use it.  As I look at the files though, they use extensions that I have never seen before and I have no idea how to actually open the thing and get started.  I've been Googling without success.  Can anybody point me in the right direction?  Does anyone actually use this?

thanks,
Al

bw_msgboard

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Apr 21, 2020, 4:35:13 PM4/21/20
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Hi Al.  I fear you may be going down a blind alley here.  POTH works, it’s just about the most reliable testing tool for making mount connections.  I think your problem lies elsewhere – for example:

 

  1. Are you 100% certain that Stellarium is connecting to the ASCOM mount driver rather than a built-in driver it has.  The name of the driver must include the ‘ASCOM’ name.
  2. Are you sure that Stellarium is not being run ‘As Admin’.
  3. Are you always using the same account on your PC.
  4. What do you mean that “POTH” didn’t work?  Did you do a setup with POTH and specify the correct ASCOM mount driver?  Did you then configure the correct serial port number in POTH?  Can you get POTH to connect to the mount when no other astro apps are running?  You can run POTH as a free-standing app, attached are the instructions for doing that.
  5. If you can get POTH connected, then try connecting PHD2.  But in that case, the mount connection will be ‘POTH”, not your iOptron ASCOM mount driver.
  6. If that works, then try one of the planetarium apps, again connecting to ‘POTH’.  If you get POTH configured correctly and talking to the mount, then you can focus on which app is having a problem.

 

Good luck,

Bruce

 


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Using POTH as a Diagnostic Tool.doc

Brian Valente

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Apr 21, 2020, 5:27:06 PM4/21/20
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>> Does anyone actually use this?


FYI many people (including myself) use stellarium and other apps (including PHD) connected to their mount, all the time.

Bruce made many good suggestions for diagnosing this. 
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