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INDI Library v2.0.6 is Released (02 Feb 2024)

Bi-monthly release with minor bug fixes and improvements

Astroberry Focuser with Adafruit Motor HAT

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I haven't got a clue how many steps I'll need with my gear ratios. I hope 20,000 is enough. When I get home I'll try to calculate it.

Edit: Good news. Assuming I am not in error. My creation takes about 14,252 steps from full in to out.
Initial gear ratio is stepped down to 50.9:1. I have then stepped it back up 1.25x with a set at 25:20 for an effective reduction of 40.72:1.
At 200 steps per revolution. I need 8144 steps to turn my focus knob once. And the focus knob turns 1.75x from full into full out. For a total travel of 14,252 steps.
Last edit: 6 years 10 months ago by Andrew.
6 years 10 months ago #16641

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I think the motor HAT work with Pi3, as its the same GPIO layout (might want to Beef your power supply up though). I haven't checked the HAT Software drivers out, but I image that they will only be dependent upon Python versions 2.7 or 3, and so not a Pi2/3 issue.
regs
rob
6 years 10 months ago #16691

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Thanks Rob. As you said it should, and indeed from my experience with one does work with the Pi3. The HAT also requires it's own power supply as it can not draw enough from the GPIO pins. There is also space on the HAT for extra custom circuitry to match the voltage requirements of the motors being used or what have you.
6 years 10 months ago #16697

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Hi Kaczorek! Excellent work on the Astroberry Server. I know that's been keeping you very busy so take your time on this, no big rush. I have just about worked out the final iteration and will be releasing the STL files for anybody who can make use of them. Thanks Again.
6 years 10 months ago #16784

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I'm glad you find it useful. I should find time for the Adafruit Motor HAT driver soon. Stay tuned
6 years 10 months ago #16785

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Kaczorek: Will there be an option for backlash steps?
6 years 10 months ago #16845

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6 years 10 months ago #16852

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Excellent! I'm looking forward to giving this a spin.
6 years 10 months ago #16853

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There's really bad news on this driver. Adafruit provides only python library for this board and no c++ library is available that can be used directly. As the result a driver for this board needs to use low level PCA9685 driver (which basically means writing everything from scratch) or bind python library into c++ code (which reuses the library but still requires lots of coding).
In summary, for now a stepper focuser build on Adafruit Motor HAT can only work outside of INDI, controlled with python scripts released by a vendor. Integration with INDI will be possible if c++ library is available for the device.
6 years 10 months ago #16883

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Oh no. That's not good.
6 years 10 months ago #16887

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I'm trying to exercise my Google Fu and have come up with a couple results, it would seem other's have the same issue.
www.chiefdelphi.com/forums/showthread.php?p=1598518
github.com/threebrooks/AdafruitStepperMotorHAT_CPP
www.raspberrypi.org/forums/viewtopic.php?t=112415&p=908267
mjmeans.github.io/Adafruit.IoT/doc/html/...21e-7d84815c826d.htm

I hope some of this can be of use.
6 years 10 months ago #16889

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It seems that the second link would be quite useful. So we're back to the game ;-)
The following user(s) said Thank You: Andrew
Last edit: 6 years 10 months ago by Radek Kaczorek.
6 years 10 months ago #16902

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