Motor Controller from Raspberry Pi

I've finally got off my backside and tested out the N20 motors I ordered what feels like a billion years ago.  Part of the delay was that I lost the original L293D motor controllers I was going to use.  I am just that awesome.

It took a little fiddling around, but I got the motor and raspberry pi powered from an ATX PSU and the pi's pins connected via an IDE cable to the L9110S module I got from ebay.

Then, I used gpiozero's PWMOutputDevice to create a forward device on one pin and a backward device on the other.  I didn't even have to faff about with the frequencies - just set the value on the object and away it went!


So now, my plan is to build the base frame for my CNC router and attach this motor to a threaded rod and rotary encoder.  Fingers crossed that tiny motor has enough torque to move the cutting tray. :S

Comments

  1. Unknown29 July 2020 at 06:25

    Hi, this is from Japan.
    Could you put the source code of it?

    ReplyDelete
    Replies
    1. GRG29 July 2020 at 08:28

      Thanks for the comment! I've got to get the source off my pi, but I'm planning to go back to this project at the weekend - I'll let you know!

      Delete
    2. GRG22 August 2020 at 07:21

      It took me a while to find the pi, but I finally have the code! I've tested it on the latest raspberry pi os image: https://www.raspberrypi.org/downloads/

      #!/usr/bin/python3
      from gpiozero import PWMOutputDevice
      from time import sleep

      motorAForward = PWMOutputDevice(17)
      motorABackward = PWMOutputDevice(18)

      try:
      while True:
      motorAForward.value=1
      sleep(1)
      motorAForward.value=0
      sleep(1)
      motorAForward.value=0.25
      sleep(1)
      motorAForward.value=0
      sleep(1)
      motorABackward.value=1
      sleep(1)
      motorABackward.value=0
      sleep(1)
      except:
      pass

      motorAForward.close()
      motorABackward.close()

      Delete

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