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INDI Library v1.9.4 Released (17 Jan 2022)

Bimonthly Stable INDI Library release introduces new drivers and fixes for existing ones. Some highlights:

INDI focuser driver for Waveshare Stepper Motor HAT for Raspberry Pi / Rock Pi

  • Posts: 304
  • Thank you received: 76
Barry,

That motor should be fine. In the default 32x microstepping configuration, it might move a little slow. If that turns out to be the case, you can change the DIP switches on the Waveshare HAT to a lower microstepping factor, to speed things up. You will need to modify the #define MICROSTEPPING at the top of the source code file to match the DIP switches, and rebuild the driver. But it will work as is, maybe just a little slow.

-- Kevin
The following user(s) said Thank You: Barry Dyer
3 months 2 weeks ago #76237

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Hi Kevin
Firstly a huge thank you for the work you've done on this driver.  It's been a lot of fun playing with getting this working on my Raspberry Pi 4 and StellarmateOS.  I have a question on microstepping and I suspect I am missing something elementary.  I have a 1.8 degree (200 steps/rev) Nema14 motor that I am trying to pair with my SVX102T refractor.  My scope has a CFZ of 111 microns and I am trying to achieve the recommended 10 steps per CFZ.  I believe that using 1/8 steps should achieve this goal, but I am a loss as to how to make the driver do this.  I tested with the Waveshare Python code (which needed to be corrected for the active high enable pin) and was able to make the stepper motor do a 1/8 rev with 200 steps:
    Motor1.SetMicroStep('hardward','1/8step')
    Motor1.TurnStep(Dir='forward', steps=200, stepdelay = 0.0001)
    time.sleep(0.5)
    Motor1.TurnStep(Dir='backward', steps=200, stepdelay = 0.0001)
    Motor1.Stop()
Questions:
  1. To make this work for the focuser, I changed the MICROSTEPPING define in wmh_focuser.cpp to 8 and set the dip switches to 110 on the board.  However, this still yields a full turn for 200 steps when I test using the Indi Control panel for the focuser. I'm sure I'm misunderstanding the intent of the MICROSTEPPING define, but for the life of my I can't figure it out. 
  2. I then figured I could put the motor onto the fine focus knob, but wouldn't that make focusing really slow?


 
1 month 1 week ago #78508

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I believe the way microstepping was implemented in the driver is for smoother and quieter motor movement rather than added precision. And a microstep position can only be held with constant power to the motor, which is not desirable. Your options are therefor to use gear reduction and backlash compensation.
INDI/KStars on Raspberry Pi 4, 4gb
Raspbian Buster with AstroPi3 script configuration
Skywatcher HEQ5 Pro Mount
Canon 600D Camera
Orion SSAG/ASI120mm @280mm Guide Scope
PHD2
Waveshare Stepper Motor Board - DIY Focuser
Adafruit GPS Module
Generic Bluetooth Joystick.
Startech 7 port powered USB Hub.
The following user(s) said Thank You: Anand Narwani
1 month 6 days ago #78544

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