Basic interface between NU32 devboard and stepper motor driver
This project implements a simple interface with a stepper motor driver (e.g., the STR8 from Applied Motion Products) using the following logic-level digital commands:
- ENABLE
- STEP
- DIRECTION
Many drivers also expose a FAULT signal. This project currently does not monitor the FAULT signal, but adding this feature is straightforward.
This project provides a text-based user interface consisting of various options which the user can select via a serial console (e.g., screen, PuTTY). This menu includes options to enable/disable the motor, enable/disable trapezoidal velocity profiles, and an option to move a user-specified number of steps.
This project contains the following C and header files:
main.c: the program entry point; implements user interface via switch statement inside an infinite while loopstepper.{c,h}: contains functions to interact with the stepper motor driverutil.{c,h}: contains helpful functions whose use can extend beyond any single library.NU32.{c,h}: the NU32 library (see http://hades.mech.northwestern.edu/index.php/NU32_Software).
This project was developed around the STR8 driver from Applied Motion Products. The STR8 accepts any voltage from 5V to 24 V as digital high, but the NU32 outputs 3.3 V as digital high. To circumvent this mismatch, I have configured the relevant NU32 digital output pins (E4, E5, and E6) as open-drain outputs; external pull-up resistors (R > 500 Ohms) are required to pull each output up to 5 V.