Need Help Selecing Cpu Board

Other Hardware 3rd Party Boards
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I am trying to control a stepper motor with a Raspberry PI-3A running Python code using the DRV882 stepper controller IC. The problem is the sleep command is only good to 0.001 seconds, any smaller value it goes out the window. So I am thinking about using an Arduino micro board to achieve the microsecond step pulses ( **delayMicroseconds** command ) I just do not know which one t to use. The unit needs to have a min of 16 pGPIO pins and a supply voltage of 5VDC. Also, a way to burn the code into the board so I do not have to reload the code every time it boots up.

Any suggestions on what high-speed stepper motor I could use? The one I am using is very slow.

Thank you for sharing your wisdom with me. :smiley: :smiley: :smiley:

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Are you accelerating the motor and it's load?

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There is no load per-say like a wench. The stepper needs a high rotating speed to smack a tool very hard. So angular velocity is what is important.

It will swing between 90 to 180 Deg ( at different speeds and angles ) and then return to a start position.

4

Actually, TORQUE is what is important. You need to use the highest voltage your controller is rated for and then set the current maximum for your motor.
For example, I have a stepper motor rated at 4.2 volts, But in a functioning commercial product with a custom controller, the power supply is 42 volts at 2 amps. They needed maximum torque for pumping drywall mud.
If your controller does not have a voltage limit of over 24 volts, get a different controller!

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I am using a 24VDC @ 8 Amps rated power supply. The driving chip can take up 47VDC.

Here is a link to the motor data sheet I am using but want to upgrade to a faster motor.

Stepper Motor Data Sheet

Back to what CPU board that fulfills the requirements I mention in the original post.

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Do have an understand of what happens with your stepper motor if you request a new step while the current step is in progress? Nothing! That is why you need maximum torque and acceleration.

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Here is the Python code that generates the step pulses with a 50% duty cycle.

  while True:
     GPIO.output(Step_Pin, not(GPIO.input(Step_Pin)))
	 sleep(Delay)

Here is a link to the motor Stepper Motor Data Sheet I do not see the torque value you talking about.

Yes, I do understand the request for a new step before the old step is not completed nothing will happen. Looking at pulses with an O-Scope the pulses are all over the place (not constant). I expected the sleep function not being constant, that's why I am looking for an Arduino board to do the required precise timing. This board will be controlled by Raspberry with a busy output so the Raspberry knows when the stepping is completed.

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Any Arduino board will do and the appropriate stepper controller. You have a good PSU.
Remember, PYTHON is ALL interpreted code, not compiled code. And it changes with every new release! Still need to accelerate the stepper motor!

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I am looking at the Adafruit ItsyBitsy 32u4 - 3V board. This unit will need to interface with, a Raspberry PI, thus the logic pins can not be over 3.3 VDC.

Does anyone know how much current it draws so I can design a power supply?

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