Why do I need a resistor and a diode in my arduino connection?

Catch671C copy

Hi guys can anyone tell me why is there an internal drawing of a resistor and a diode on the arduino schematic? I want to receive feedback from my hybrid stepper driver but it doesn't receive any output, do I put the resistor and the diode in between the (pend-) and (IN) of the arduino?

Thank you!

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Hi LarryD! thats a Stepper Driver but its called a Hybrid Stepper Driver

What you call Arduino looks like an optocoupler to me.

Can you provide the source of your diagram.

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The above is the description in our manual.
MF is what we often call ENA, that is, enable.
Generally speaking, enabling can control whether the motor is controlled.
If the motor is controlled and the controller sends pulses, the motor will respond accordingly.
If the motor is not controlled, the drive will not energize the motor, and the motor will have no response when the controller sends pulses. At this time, the motor shaft is free because there is no current.
When MF+ and MF- are not connected, the motor is enabled, which means that the motor is controlled. If MF+ and MF- are connected, the user will control whether the motor is enabled.

PEND is an in-position signal. When the in-position signal is valid, after the driver completes the given pulse (under normal circumstances, it can also be considered as the motor completes the given action), PEND will send out a signal.

I don't know why arduino doesn't receive any signal, I'm out of thoughts..

Pend+ is connected to the positive terminal of the arduino 5V

Pend- is connected to the pin 12 (PWM) of the arduino

Do I need a real servo driver to get feedbacks from the motor? Or the function of PEND does not return a feedback that indicates where the stepper motor stopped? I watched several youtube videos and their examples of the stepper feedback only include 1 wire, and the other two is for voltage and ground. Maybe thats what I get for going for cheaper drives?


However we need to see the actual electronics that those pins are connected to.

Example: is it dry or wet relay contacts, maybe an open collector PNP or NPN transistor.

You should be able to find a schematic of the output to these terminals.

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