ASCOM Alpaca & NodeRed for Open Astronomy

General
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Hello good people,

I hope all of you are doing great and healthy, mentally and physically.

I am an amateur astronomer and now working in an backyard Observatory and Planetarium called ImahNoong, located in Lembang, Indonesia. So I have been working with astro instruments and integrating it with ASCOM Protocol, only as a user. But I also used NodeRed for some of the automation around the observatory such as the sliding roof.

ASCOM released a new protocol using HTTP and JSON to send and receive commands, called ASCOM Alpaca, I really like NodeRed because of it's flexibility and robustness, but I don't know how to connect them together, below are some resources that I've been reading to understand how ASCOM Alpaca works, but I still don't get it.

I am planning to use Raspberry pi to control the hardware (Sliding Roof) using the GPIO, so that's why NodeRed came to my mind as the go to solution.

I hope this post will spark a discussion and some suggestions on how I can better understand the system.

Thank you,

Best Regards,
Arifin

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Hi, the ASCOM Alpaca API is said to be a REST interface. You could most likely just use the "http request" node to send commands. The documentation is full of examples for various url's and methods. What have you tried so far?

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Hello, thank you for answering. The main problem is my inability of making the first step, because I still don't understand REST Interface. I still can't draw the whole concept in my mind on how the instrument and the protocol working together.

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There are many good resources out there, plenty on utube for example. Have you looked?

I've not tried Alpaca yet but run ASCOM as the interface for cameras, mount etc. But no connection with NR yet.

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The first example above is checking the connection status. The second is an example checking the "Interface version". The api documentation provides you with many more examples but this should get you going. I'm not going to share the flows, learning by typing is much better

Here are the configurations for the http nodes respectively:

In this one, using the test server

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For this one, you have to modify the ip and eventually the port nbr according to your local settings

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