Thank you very much for your quick reply. I tried to find some documentation of the EQUATORIAL_PE property in the web, but this was unsuccessful. I then tried to just replace EQUATORIAL_EOD_COORD with EQUATORIAL_PE in my example code. That was how I interpreted your short comment in your post:

# get coordinate object
    equatorial_pe = None
    while not equatorial_pe:
        time.sleep(0.5)
        equatorial_pe = device.getNumber("EQUATORIAL_PE")

    # Slew to fixed position in the sky.
    ra = 1.5
    de = 25.4
    print("Slew to RA= " + str(ra) + ", DE= " + str(de))
    equatorial_pe[0].value = ra
    equatorial_pe[1].value = de
    indiclient.sendNewNumber(equatorial_pe)

    # get pulse guide objects
    telescope_guideNS = None
    while not telescope_guideNS:
        time.sleep(0.5)
        telescope_guideNS = device.getNumber("TELESCOPE_TIMED_GUIDE_NS")

    # # wait until the scope has finished moving
    # while equatorial_pe.s == PyIndi.IPS_BUSY:
    #     time.sleep(0.2)

    # Stationary state reached, store measured position.
    ra_before = equatorial_pe[0].value
    de_before = equatorial_pe[1].value

    # Issue an INDI "move north" instruction and wait a short time.
    print("Move north 10000 milliseconds.")
    telescope_guideNS[0].value = 1000.
    telescope_guideNS[1].value = 0
    indiclient.sendNewNumber(telescope_guideNS)
    time.sleep(4.)

    # # wait until the scope has finished moving
    # while equatorial_pe.s == PyIndi.IPS_BUSY:
    #     time.sleep(0.2)

    # Stationary state reached, store measured position.
    ra_after = equatorial_pe[0].value
    de_after = equatorial_pe[1].value
    print("The telescope has moved north by "+str(3600*(de_after-de_before)) + "arc seconds.")
The first thing I noticed is that waiting for the telecscope to finish moving does not seem to work as with EQUATORIAL_EOD_COORD, so I commented it out. Then the code ran through without errors. When I looked at the Ekos window of the telescope simulator, however, I saw that the RA/DEC coordinates do not change with the initial slew-to operation. It seems, therefore, that EQUATORIAL_PE is not just the replacement of EQUATORIAL_EOD_COORD for the case of the telescope simulator. And the result was the same as before: 0.0 arc seconds movement with the guideNS operation.

I'm very frustrated with the almost complete absence of documentation for the whole INDI system. Is there any place in the web where I can find how to use the telescope interface from Python? It is very difficult to find out everything by trial and error.

All the best,
Rolf

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